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Re: [SeattleRobotics] Motors and Encoders

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  • Gustavo
    Sorry, Maybe I didn t make myself clear when I said : I don t want to use and external gear train, I cant put the motors side by side... I meant that the
    Message 1 of 15 , Aug 5, 2003
      Sorry, Maybe I didn't make myself clear when I said :

      I don't want to use and external gear train, I cant put the motors side by side...

      I meant that the motors have to be like this:
      _______ ______
      shaft | | | |shaft
      --------|motor1 | |motor2 |--------
      |______| |______|


      and not like:


      ___|___ ___|___
      | | | |
      |Motor1| |Motor2 |
      |______| |______ |


      or:

      |Gear
      | ________
      \/ | |
      *-------|Motor1 |
      |_______ |
      * ________ * bigger gear
      ^ | |
      | |Motor2 |----------*
      | |_______ | ^
      | gear
      bigger gear

      the bigger gear is connected to the shaft.


      (Forgive me for the horrible ASCII art.)



      ----- Original Message -----
      From: "Gustavo" <gustavo@...>
      To: <seattlerobotics@yahoogroups.com>
      Sent: Tuesday, August 05, 2003 5:10 AM
      Subject: [SeattleRobotics] Motors and Encoders


      > Hello,
      >
      > I'm looking for a suitable encoder, and motor (it doesn't necessarily have to be a single package) for a micromouse robot. I have tried to salvage optical encoders from computer mice, but I can't seem to get them coupled on the axles. I have thought of printing out an encoder on a transparency, but then it would be difficult to align, and it would probably bend. I have also though of just printing out an encoder with the sectors alternating black and white, but then I face two problems, the lack of resolution, and precision, and the lighting conditions that might affect the reading of the sensor. I don't need a lot of resolution, but at least around 30. as for the actual sensor, I don't need a quadrature because the direction that the motor is going is not needed (I control the motors, I know the direction I set them).
      >
      > As for the motors, I haven't tried servos, and I don't want to use them for rotations, if I do incorporate servos, it will be for rotating a "head" with various sensors. I need something with speed (I would like the mouse to go at about 1 meter per second, or maybe faster)
      > The maximum size for the robot is 16.8 cm. (~6.6 in) squared because the passage way is 18 cm. (~7 in) and the wall width is 1.2 cm (~.47 in). But I would the like the robot to be smaller than that to be able to maneuver easily. The width of the robot is going to have to be to be is around 11 cm (4.4 in) if the base is a square, if it is a circle, it could be slightly bigger. so the maximum length of the motors would have to be 5.5 cm (2.2 in) because I don't want to use and external gear train, I cant put the motors side by side, and if the encoder is on the shaft of the motor then I can't put and other gears because of the spacing in between the gear (each gear can rotate freely a few degrees). The motor should have a gear train, even if it is outside in a box.
      > I have also though about the possibility of using stepper motors. This way I wouldn't need to use the encoder, unless the wheel slips, or the stepper motor looses some steps. But stepper motors are hard to mount because most of them have a pinion gear on there shaft, and the ones used in old 5 1/4 drives weight too much. But it is something that I am considering.
      > I have tried to use a Lego design (I've built Lego robots for 2 years with the Mindstorm line of kits, I've stopped now) but I couldn't get it to be small enough the Lego gear motors are really good, but they also go slow, and I had a difficult time mounting the encoder, so I tried to use a gear, but the design wouldn't be small enough. I then though about the Lego rotation sensor, but its signal is analog, there are 4 different voltage level, at for different parts of the cycle, but then this would require either a port on the ADC, or 4 comparators (the 339 chip) and it would waste 4 I/O pins. AND it would be inaccurate for high speeds.
      >
      >
      >
      > BTW. this is for my 7th grade science project. Idea of the project is to identify which algorithm is more efficient, and faster in solving the maze. I may make the use a different maze then the ones used in micromouse compition (maybe less cells, or the beginning and end location is different). I chose this idea because it is more of a programming project, then a hardware project, and I am better at software than hardware, I don't really have any mechanical skills, which is why I want to keep the actual motor hardware simple. My dad can help me with the mechanical aspects of the project.
      >
      > These are some micromouse links if you want more information
      >
      > http://micromouse.cannock.ac.uk/
      >
      > http://micromouse.cs.rhbnc.ac.uk/
      >
      > http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
      >
      > http://fused.org/projects/
      >
      > http://www.cs.rhul.ac.uk/eca/micromouse/
      >
      > http://www.ece.ucdavis.edu/umouse/
      >
      >
      > And help is appreciated
      >
      > Rgds,
      > Gustavo
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      >
      > [Non-text portions of this message have been removed]
      >
      >
      > Visit the SRS Website at http://www.seattlerobotics.org
      >
      > To unsubscribe from this group, send an email to:
      > SeattleRobotics-unsubscribe@yahoogroups.com
      >
      >
      > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
      >
      >

      [Non-text portions of this message have been removed]
    • Tom Capon
      Well, I think you re going to have a tough time making something that small and that fast. You might want to look into pager motors, they can be found most
      Message 2 of 15 , Aug 5, 2003
        Well, I think you're going to have a tough time making something that small
        and that fast. You might want to look into pager motors, they can be found
        most any surplus house. Assuming you're running this thing on a flat
        table-top-like surface, you might even want to use a mouse as the body of
        the robot. There are sites that explain how to hack a mouse to get the
        encoder signals right out of the board without have to add your own drivers
        and stuff. The only problem with the pager motors is that the are
        fast. You would have to get about four of them maybe and put the
        (computer) mouse on wheels. Just slip a bit of rubber tubing (really small
        diameter) over the motor shaft and you've got a fairly good tire that will
        gear it down a lot just by being small. If you get an optical mouse,
        (under $20, probably) there would be much less friction and it would be
        easier to control. there is a link to a site on how to hack an optical
        mouse for encoder-like outputs on my site,
        www.destructonet.org/tom/robotics . BTW, what microcontroller are you using?


        At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
        >Sorry, Maybe I didn't make myself clear when I said :
        >
        >I don't want to use and external gear train, I cant put the motors side by
        >side...
        >
        >I meant that the motors have to be like this:
        > _______ ______
        >shaft | | | |shaft
        >--------|motor1 | |motor2 |--------
        > |______| |______|
        >
        >
        >and not like:
        >
        >
        >___|___ ___|___
        >| | | |
        >|Motor1| |Motor2 |
        >|______| |______ |
        >
        >
        >or:
        >
        > |Gear
        > | ________
        >\/ | |
        >*-------|Motor1 |
        > |_______ |
        >* ________ * bigger gear
        >^ | |
        >| |Motor2 |----------*
        >| |_______ | ^
        >| gear
        >bigger gear
        >
        > the bigger gear is connected to the shaft.
        >
        >
        >(Forgive me for the horrible ASCII art.)
        >
        >
        >
        >----- Original Message -----
        >From: "Gustavo" <gustavo@...>
        >To: <seattlerobotics@yahoogroups.com>
        >Sent: Tuesday, August 05, 2003 5:10 AM
        >Subject: [SeattleRobotics] Motors and Encoders
        >
        >
        > > Hello,
        > >
        > > I'm looking for a suitable encoder, and motor (it doesn't
        > necessarily have to be a single package) for a micromouse robot. I have
        > tried to salvage optical encoders from computer mice, but I can't seem to
        > get them coupled on the axles. I have thought of printing out an encoder
        > on a transparency, but then it would be difficult to align, and it would
        > probably bend. I have also though of just printing out an encoder with
        > the sectors alternating black and white, but then I face two problems,
        > the lack of resolution, and precision, and the lighting conditions that
        > might affect the reading of the sensor. I don't need a lot of resolution,
        > but at least around 30. as for the actual sensor, I don't need a
        > quadrature because the direction that the motor is going is not needed (I
        > control the motors, I know the direction I set them).
        > >
        > > As for the motors, I haven't tried servos, and I don't want to use
        > them for rotations, if I do incorporate servos, it will be for rotating a
        > "head" with various sensors. I need something with speed (I would like
        > the mouse to go at about 1 meter per second, or maybe faster)
        > > The maximum size for the robot is 16.8 cm. (~6.6 in) squared
        > because the passage way is 18 cm. (~7 in) and the wall width is 1.2 cm
        > (~.47 in). But I would the like the robot to be smaller than that to be
        > able to maneuver easily. The width of the robot is going to have to be to
        > be is around 11 cm (4.4 in) if the base is a square, if it is a circle,
        > it could be slightly bigger. so the maximum length of the motors would
        > have to be 5.5 cm (2.2 in) because I don't want to use and external gear
        > train, I cant put the motors side by side, and if the encoder is on the
        > shaft of the motor then I can't put and other gears because of the
        > spacing in between the gear (each gear can rotate freely a few degrees).
        > The motor should have a gear train, even if it is outside in a box.
        > > I have also though about the possibility of using stepper motors.
        > This way I wouldn't need to use the encoder, unless the wheel slips, or
        > the stepper motor looses some steps. But stepper motors are hard to mount
        > because most of them have a pinion gear on there shaft, and the ones used
        > in old 5 1/4 drives weight too much. But it is something that I am considering.
        > > I have tried to use a Lego design (I've built Lego robots for 2
        > years with the Mindstorm line of kits, I've stopped now) but I couldn't
        > get it to be small enough the Lego gear motors are really good, but they
        > also go slow, and I had a difficult time mounting the encoder, so I tried
        > to use a gear, but the design wouldn't be small enough. I then though
        > about the Lego rotation sensor, but its signal is analog, there are 4
        > different voltage level, at for different parts of the cycle, but then
        > this would require either a port on the ADC, or 4 comparators (the 339
        > chip) and it would waste 4 I/O pins. AND it would be inaccurate for high
        > speeds.
        > >
        > >
        > >
        > > BTW. this is for my 7th grade science project. Idea of the project
        > is to identify which algorithm is more efficient, and faster in solving
        > the maze. I may make the use a different maze then the ones used in
        > micromouse compition (maybe less cells, or the beginning and end location
        > is different). I chose this idea because it is more of a programming
        > project, then a hardware project, and I am better at software than
        > hardware, I don't really have any mechanical skills, which is why I want
        > to keep the actual motor hardware simple. My dad can help me with the
        > mechanical aspects of the project.
        > >
        > > These are some micromouse links if you want more information
        > >
        > > http://micromouse.cannock.ac.uk/
        > >
        > > http://micromouse.cs.rhbnc.ac.uk/
        > >
        > > http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
        > >
        > > http://fused.org/projects/
        > >
        > > http://www.cs.rhul.ac.uk/eca/micromouse/
        > >
        > > http://www.ece.ucdavis.edu/umouse/
        > >
        > >
        > > And help is appreciated
        > >
        > > Rgds,
        > > Gustavo
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > >
        > > [Non-text portions of this message have been removed]
        > >
        > >
        > > Visit the SRS Website at http://www.seattlerobotics.org
        > >
        > > To unsubscribe from this group, send an email to:
        > > SeattleRobotics-unsubscribe@yahoogroups.com
        > >
        > >
        > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
        > >
        > >
        >
        >[Non-text portions of this message have been removed]
        >
        >
        >Visit the SRS Website at http://www.seattlerobotics.org
        >
        >To unsubscribe from this group, send an email to:
        >SeattleRobotics-unsubscribe@yahoogroups.com
        >
        >
        >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
      • Gustavo
        How do the other micromice (can t think of a better word!) achieve this size and speed? I am currently learning how to use the ATMega16 / 32 because of its
        Message 3 of 15 , Aug 5, 2003
          How do the other micromice (can't think of a better word!) achieve this
          size and speed?
          I am currently learning how to use the ATMega16 / 32 because of its speed,
          but I am also learning how to program the Rabbitcore 2000 from
          http://www.rabbitsemiconductor.com/. It has a lot of RAM , and program
          memory, and has four serial ports. If I do use both of these processors then
          the Rabbit would be the master, and the ATMega would be the slave. I am
          planning in using the ATMega for controlling the motors, and reading the
          encoder and reading the other sensors (It has a built in ADC).



          ----- Original Message -----
          From: "Tom Capon" <robot@...>
          To: <seattlerobotics@yahoogroups.com>
          Sent: Tuesday, August 05, 2003 11:24 AM
          Subject: Re: [SeattleRobotics] Motors and Encoders


          >
          > Well, I think you're going to have a tough time making something that
          small
          > and that fast. You might want to look into pager motors, they can be
          found
          > most any surplus house. Assuming you're running this thing on a flat
          > table-top-like surface, you might even want to use a mouse as the body of
          > the robot. There are sites that explain how to hack a mouse to get the
          > encoder signals right out of the board without have to add your own
          drivers
          > and stuff. The only problem with the pager motors is that the are
          > fast. You would have to get about four of them maybe and put the
          > (computer) mouse on wheels. Just slip a bit of rubber tubing (really
          small
          > diameter) over the motor shaft and you've got a fairly good tire that will
          > gear it down a lot just by being small. If you get an optical mouse,
          > (under $20, probably) there would be much less friction and it would be
          > easier to control. there is a link to a site on how to hack an optical
          > mouse for encoder-like outputs on my site,
          > www.destructonet.org/tom/robotics . BTW, what microcontroller are you
          using?
          >
          >
          > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
          > >Sorry, Maybe I didn't make myself clear when I said :
          > >
          > >I don't want to use and external gear train, I cant put the motors side
          by
          > >side...
          > >
          > >I meant that the motors have to be like this:
          > > _______ ______
          > >shaft | | | |shaft
          > >--------|motor1 | |motor2 |--------
          > > |______| |______|
          > >
          > >
          > >and not like:
          > >
          > >
          > >___|___ ___|___
          > >| | | |
          > >|Motor1| |Motor2 |
          > >|______| |______ |
          > >
          > >
          > >or:
          > >
          > > |Gear
          > > | ________
          > >\/ | |
          > >*-------|Motor1 |
          > > |_______ |
          > >* ________ * bigger gear
          > >^ | |
          > >| |Motor2 |----------*
          > >| |_______ | ^
          > >| gear
          > >bigger gear
          > >
          > > the bigger gear is connected to the shaft.
          > >
          > >
          > >(Forgive me for the horrible ASCII art.)
          > >
          > >
          > >
          > >----- Original Message -----
          > >From: "Gustavo" <gustavo@...>
          > >To: <seattlerobotics@yahoogroups.com>
          > >Sent: Tuesday, August 05, 2003 5:10 AM
          > >Subject: [SeattleRobotics] Motors and Encoders
          > >
          > >
          > > > Hello,
          > > >
          > > > I'm looking for a suitable encoder, and motor (it doesn't
          > > necessarily have to be a single package) for a micromouse robot. I have
          > > tried to salvage optical encoders from computer mice, but I can't seem
          to
          > > get them coupled on the axles. I have thought of printing out an encoder
          > > on a transparency, but then it would be difficult to align, and it would
          > > probably bend. I have also though of just printing out an encoder with
          > > the sectors alternating black and white, but then I face two problems,
          > > the lack of resolution, and precision, and the lighting conditions that
          > > might affect the reading of the sensor. I don't need a lot of
          resolution,
          > > but at least around 30. as for the actual sensor, I don't need a
          > > quadrature because the direction that the motor is going is not needed
          (I
          > > control the motors, I know the direction I set them).
          > > >
          > > > As for the motors, I haven't tried servos, and I don't want to use
          > > them for rotations, if I do incorporate servos, it will be for rotating
          a
          > > "head" with various sensors. I need something with speed (I would like
          > > the mouse to go at about 1 meter per second, or maybe faster)
          > > > The maximum size for the robot is 16.8 cm. (~6.6 in) squared
          > > because the passage way is 18 cm. (~7 in) and the wall width is 1.2 cm
          > > (~.47 in). But I would the like the robot to be smaller than that to be
          > > able to maneuver easily. The width of the robot is going to have to be
          to
          > > be is around 11 cm (4.4 in) if the base is a square, if it is a circle,
          > > it could be slightly bigger. so the maximum length of the motors would
          > > have to be 5.5 cm (2.2 in) because I don't want to use and external gear
          > > train, I cant put the motors side by side, and if the encoder is on the
          > > shaft of the motor then I can't put and other gears because of the
          > > spacing in between the gear (each gear can rotate freely a few degrees).
          > > The motor should have a gear train, even if it is outside in a box.
          > > > I have also though about the possibility of using stepper motors.
          > > This way I wouldn't need to use the encoder, unless the wheel slips, or
          > > the stepper motor looses some steps. But stepper motors are hard to
          mount
          > > because most of them have a pinion gear on there shaft, and the ones
          used
          > > in old 5 1/4 drives weight too much. But it is something that I am
          considering.
          > > > I have tried to use a Lego design (I've built Lego robots for 2
          > > years with the Mindstorm line of kits, I've stopped now) but I couldn't
          > > get it to be small enough the Lego gear motors are really good, but they
          > > also go slow, and I had a difficult time mounting the encoder, so I
          tried
          > > to use a gear, but the design wouldn't be small enough. I then though
          > > about the Lego rotation sensor, but its signal is analog, there are 4
          > > different voltage level, at for different parts of the cycle, but then
          > > this would require either a port on the ADC, or 4 comparators (the 339
          > > chip) and it would waste 4 I/O pins. AND it would be inaccurate for
          high
          > > speeds.
          > > >
          > > >
          > > >
          > > > BTW. this is for my 7th grade science project. Idea of the project
          > > is to identify which algorithm is more efficient, and faster in solving
          > > the maze. I may make the use a different maze then the ones used in
          > > micromouse compition (maybe less cells, or the beginning and end
          location
          > > is different). I chose this idea because it is more of a programming
          > > project, then a hardware project, and I am better at software than
          > > hardware, I don't really have any mechanical skills, which is why I want
          > > to keep the actual motor hardware simple. My dad can help me with the
          > > mechanical aspects of the project.
          > > >
          > > > These are some micromouse links if you want more information
          > > >
          > > > http://micromouse.cannock.ac.uk/
          > > >
          > > > http://micromouse.cs.rhbnc.ac.uk/
          > > >
          > > > http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
          > > >
          > > > http://fused.org/projects/
          > > >
          > > > http://www.cs.rhul.ac.uk/eca/micromouse/
          > > >
          > > > http://www.ece.ucdavis.edu/umouse/
          > > >
          > > >
          > > > And help is appreciated
          > > >
          > > > Rgds,
          > > > Gustavo
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > > [Non-text portions of this message have been removed]
          > > >
          > > >
          > > > Visit the SRS Website at http://www.seattlerobotics.org
          > > >
          > > > To unsubscribe from this group, send an email to:
          > > > SeattleRobotics-unsubscribe@yahoogroups.com
          > > >
          > > >
          > > > Your use of Yahoo! Groups is subject to
          http://docs.yahoo.com/info/terms/
          > > >
          > > >
          > >
          > >[Non-text portions of this message have been removed]
          > >
          > >
          > >Visit the SRS Website at http://www.seattlerobotics.org
          > >
          > >To unsubscribe from this group, send an email to:
          > >SeattleRobotics-unsubscribe@yahoogroups.com
          > >
          > >
          > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
          >
          >
          > Visit the SRS Website at http://www.seattlerobotics.org
          >
          > To unsubscribe from this group, send an email to:
          > SeattleRobotics-unsubscribe@yahoogroups.com
          >
          >
          > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
          >
          >
          >
        • Jim McBride
          You may want to explore BEAM applications for small motors. Solarbotics.com has a lot of useful miniature items.
          Message 4 of 15 , Aug 5, 2003
            You may want to explore BEAM applications for small motors. Solarbotics.com
            has a lot of useful miniature items.
            http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8

            Jim

            At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
            > How do the other micromice (can't think of a better word!) achieve this
            >size and speed?
            >I am currently learning how to use the ATMega16 / 32 because of its speed,
            >but I am also learning how to program the Rabbitcore 2000 from
            >http://www.rabbitsemiconductor.com/. It has a lot of RAM , and program
            >memory, and has four serial ports. If I do use both of these processors then
            >the Rabbit would be the master, and the ATMega would be the slave. I am
            >planning in using the ATMega for controlling the motors, and reading the
            >encoder and reading the other sensors (It has a built in ADC).
            >
            >
            >
            >----- Original Message -----
            >From: "Tom Capon" <robot@...>
            >To: <seattlerobotics@yahoogroups.com>
            >Sent: Tuesday, August 05, 2003 11:24 AM
            >Subject: Re: [SeattleRobotics] Motors and Encoders
            >
            >
            > >
            > > Well, I think you're going to have a tough time making something that
            >small
            > > and that fast. You might want to look into pager motors, they can be
            >found
            > > most any surplus house. Assuming you're running this thing on a flat
            > > table-top-like surface, you might even want to use a mouse as the body of
            > > the robot. There are sites that explain how to hack a mouse to get the
            > > encoder signals right out of the board without have to add your own
            >drivers
            > > and stuff. The only problem with the pager motors is that the are
            > > fast. You would have to get about four of them maybe and put the
            > > (computer) mouse on wheels. Just slip a bit of rubber tubing (really
            >small
            > > diameter) over the motor shaft and you've got a fairly good tire that will
            > > gear it down a lot just by being small. If you get an optical mouse,
            > > (under $20, probably) there would be much less friction and it would be
            > > easier to control. there is a link to a site on how to hack an optical
            > > mouse for encoder-like outputs on my site,
            > > www.destructonet.org/tom/robotics . BTW, what microcontroller are you
            >using?
            > >
            > >
            > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
            > > >Sorry, Maybe I didn't make myself clear when I said :
            > > >
            > > >I don't want to use and external gear train, I cant put the motors side
            >by
            > > >side...
            > > >
            > > >I meant that the motors have to be like this:
            > > > _______ ______
            > > >shaft | | | |shaft
            > > >--------|motor1 | |motor2 |--------
            > > > |______| |______|
            > > >
            > > >
            > > >and not like:
            > > >
            > > >
            > > >___|___ ___|___
            > > >| | | |
            > > >|Motor1| |Motor2 |
            > > >|______| |______ |
            > > >
            > > >
            > > >or:
            > > >
            > > > |Gear
            > > > | ________
            > > >\/ | |
            > > >*-------|Motor1 |
            > > > |_______ |
            > > >* ________ * bigger gear
            > > >^ | |
            > > >| |Motor2 |----------*
            > > >| |_______ | ^
            > > >| gear
            > > >bigger gear
            > > >
            > > > the bigger gear is connected to the shaft.
            > > >
            > > >
            > > >(Forgive me for the horrible ASCII art.)
            > > >
            > > >
            > > >
            > > >----- Original Message -----
            > > >From: "Gustavo" <gustavo@...>
            > > >To: <seattlerobotics@yahoogroups.com>
            > > >Sent: Tuesday, August 05, 2003 5:10 AM
            > > >Subject: [SeattleRobotics] Motors and Encoders
            > > >
            > > >
            > > > > Hello,
            > > > >
            > > > > I'm looking for a suitable encoder, and motor (it doesn't
            > > > necessarily have to be a single package) for a micromouse robot. I have
            > > > tried to salvage optical encoders from computer mice, but I can't seem
            >to
            > > > get them coupled on the axles. I have thought of printing out an encoder
            > > > on a transparency, but then it would be difficult to align, and it would
            > > > probably bend. I have also though of just printing out an encoder with
            > > > the sectors alternating black and white, but then I face two problems,
            > > > the lack of resolution, and precision, and the lighting conditions that
            > > > might affect the reading of the sensor. I don't need a lot of
            >resolution,
            > > > but at least around 30. as for the actual sensor, I don't need a
            > > > quadrature because the direction that the motor is going is not needed
            >(I
            > > > control the motors, I know the direction I set them).
            > > > >
            > > > > As for the motors, I haven't tried servos, and I don't want to use
            > > > them for rotations, if I do incorporate servos, it will be for rotating
            >a
            > > > "head" with various sensors. I need something with speed (I would like
            > > > the mouse to go at about 1 meter per second, or maybe faster)
            > > > > The maximum size for the robot is 16.8 cm. (~6.6 in) squared
            > > > because the passage way is 18 cm. (~7 in) and the wall width is 1.2 cm
            > > > (~.47 in). But I would the like the robot to be smaller than that to be
            > > > able to maneuver easily. The width of the robot is going to have to be
            >to
            > > > be is around 11 cm (4.4 in) if the base is a square, if it is a circle,
            > > > it could be slightly bigger. so the maximum length of the motors would
            > > > have to be 5.5 cm (2.2 in) because I don't want to use and external gear
            > > > train, I cant put the motors side by side, and if the encoder is on the
            > > > shaft of the motor then I can't put and other gears because of the
            > > > spacing in between the gear (each gear can rotate freely a few degrees).
            > > > The motor should have a gear train, even if it is outside in a box.
            > > > > I have also though about the possibility of using stepper motors.
            > > > This way I wouldn't need to use the encoder, unless the wheel slips, or
            > > > the stepper motor looses some steps. But stepper motors are hard to
            >mount
            > > > because most of them have a pinion gear on there shaft, and the ones
            >used
            > > > in old 5 1/4 drives weight too much. But it is something that I am
            >considering.
            > > > > I have tried to use a Lego design (I've built Lego robots for 2
            > > > years with the Mindstorm line of kits, I've stopped now) but I couldn't
            > > > get it to be small enough the Lego gear motors are really good, but they
            > > > also go slow, and I had a difficult time mounting the encoder, so I
            >tried
            > > > to use a gear, but the design wouldn't be small enough. I then though
            > > > about the Lego rotation sensor, but its signal is analog, there are 4
            > > > different voltage level, at for different parts of the cycle, but then
            > > > this would require either a port on the ADC, or 4 comparators (the 339
            > > > chip) and it would waste 4 I/O pins. AND it would be inaccurate for
            >high
            > > > speeds.
            > > > >
            > > > >
            > > > >
            > > > > BTW. this is for my 7th grade science project. Idea of the project
            > > > is to identify which algorithm is more efficient, and faster in solving
            > > > the maze. I may make the use a different maze then the ones used in
            > > > micromouse compition (maybe less cells, or the beginning and end
            >location
            > > > is different). I chose this idea because it is more of a programming
            > > > project, then a hardware project, and I am better at software than
            > > > hardware, I don't really have any mechanical skills, which is why I want
            > > > to keep the actual motor hardware simple. My dad can help me with the
            > > > mechanical aspects of the project.
            > > > >
            > > > > These are some micromouse links if you want more information
            > > > >
            > > > > http://micromouse.cannock.ac.uk/
            > > > >
            > > > > http://micromouse.cs.rhbnc.ac.uk/
            > > > >
            > > > > http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
            > > > >
            > > > > http://fused.org/projects/
            > > > >
            > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
            > > > >
            > > > > http://www.ece.ucdavis.edu/umouse/
            > > > >
            > > > >
            > > > > And help is appreciated
            > > > >
            > > > > Rgds,
            > > > > Gustavo
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > >
            > > > > [Non-text portions of this message have been removed]
            > > > >
            > > > >
            > > > > Visit the SRS Website at http://www.seattlerobotics.org
            > > > >
            > > > > To unsubscribe from this group, send an email to:
            > > > > SeattleRobotics-unsubscribe@yahoogroups.com
            > > > >
            > > > >
            > > > > Your use of Yahoo! Groups is subject to
            >http://docs.yahoo.com/info/terms/
            > > > >
            > > > >
            > > >
            > > >[Non-text portions of this message have been removed]
            > > >
            > > >
            > > >Visit the SRS Website at http://www.seattlerobotics.org
            > > >
            > > >To unsubscribe from this group, send an email to:
            > > >SeattleRobotics-unsubscribe@yahoogroups.com
            > > >
            > > >
            > > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
            > >
            > >
            > > Visit the SRS Website at http://www.seattlerobotics.org
            > >
            > > To unsubscribe from this group, send an email to:
            > > SeattleRobotics-unsubscribe@yahoogroups.com
            > >
            > >
            > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
            > >
            > >
            > >
            >
            >
            >Visit the SRS Website at http://www.seattlerobotics.org
            >
            >To unsubscribe from this group, send an email to:
            >SeattleRobotics-unsubscribe@yahoogroups.com
            >
            >
            >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
          • Gustavo
            The pager motors are very fast, but they have near to no torque. I took a look at the Solorbotics website before, and the motors seem very good, but I don t
            Message 5 of 15 , Aug 6, 2003
              The pager motors are very fast, but they have near to no torque.
              I took a look at the Solorbotics website before, and the motors seem very
              good, but I don't think they are fast enough.
              I don't understand about what you mean that I don't know the direction the
              motor is going. If you apply power to it in a certain polarity it will go on
              way, and if you reverse the polarity it will rotate the other way (Not true
              for AC motors, or brushless fan motors).
              ----- Original Message -----
              From: "Jim McBride" <mcbride7@...>
              To: <seattlerobotics@yahoogroups.com>
              Sent: Tuesday, August 05, 2003 10:27 PM
              Subject: Re: [SeattleRobotics] Motors and Encoders


              > You may want to explore BEAM applications for small motors.
              Solarbotics.com
              > has a lot of useful miniature items.
              > http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
              >
              > Jim
              >
              > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
              > > How do the other micromice (can't think of a better word!) achieve
              this
              > >size and speed?
              > >I am currently learning how to use the ATMega16 / 32 because of its
              speed,
              > >but I am also learning how to program the Rabbitcore 2000 from
              > >http://www.rabbitsemiconductor.com/. It has a lot of RAM , and program
              > >memory, and has four serial ports. If I do use both of these processors
              then
              > >the Rabbit would be the master, and the ATMega would be the slave. I am
              > >planning in using the ATMega for controlling the motors, and reading the
              > >encoder and reading the other sensors (It has a built in ADC).
              > >
              > >
              > >
              > >----- Original Message -----
              > >From: "Tom Capon" <robot@...>
              > >To: <seattlerobotics@yahoogroups.com>
              > >Sent: Tuesday, August 05, 2003 11:24 AM
              > >Subject: Re: [SeattleRobotics] Motors and Encoders
              > >
              > >
              > > >
              > > > Well, I think you're going to have a tough time making something that
              > >small
              > > > and that fast. You might want to look into pager motors, they can be
              > >found
              > > > most any surplus house. Assuming you're running this thing on a flat
              > > > table-top-like surface, you might even want to use a mouse as the body
              of
              > > > the robot. There are sites that explain how to hack a mouse to get
              the
              > > > encoder signals right out of the board without have to add your own
              > >drivers
              > > > and stuff. The only problem with the pager motors is that the are
              > > > fast. You would have to get about four of them maybe and put the
              > > > (computer) mouse on wheels. Just slip a bit of rubber tubing (really
              > >small
              > > > diameter) over the motor shaft and you've got a fairly good tire that
              will
              > > > gear it down a lot just by being small. If you get an optical mouse,
              > > > (under $20, probably) there would be much less friction and it would
              be
              > > > easier to control. there is a link to a site on how to hack an
              optical
              > > > mouse for encoder-like outputs on my site,
              > > > www.destructonet.org/tom/robotics . BTW, what microcontroller are you
              > >using?
              > > >
              > > >
              > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
              > > > >Sorry, Maybe I didn't make myself clear when I said :
              > > > >
              > > > >I don't want to use and external gear train, I cant put the motors
              side
              > >by
              > > > >side...
              > > > >
              > > > >I meant that the motors have to be like this:
              > > > > _______ ______
              > > > >shaft | | | |shaft
              > > > >--------|motor1 | |motor2 |--------
              > > > > |______| |______|
              > > > >
              > > > >
              > > > >and not like:
              > > > >
              > > > >
              > > > >___|___ ___|___
              > > > >| | | |
              > > > >|Motor1| |Motor2 |
              > > > >|______| |______ |
              > > > >
              > > > >
              > > > >or:
              > > > >
              > > > > |Gear
              > > > > | ________
              > > > >\/ | |
              > > > >*-------|Motor1 |
              > > > > |_______ |
              > > > >* ________ * bigger gear
              > > > >^ | |
              > > > >| |Motor2 |----------*
              > > > >| |_______ | ^
              > > > >| gear
              > > > >bigger gear
              > > > >
              > > > > the bigger gear is connected to the shaft.
              > > > >
              > > > >
              > > > >(Forgive me for the horrible ASCII art.)
              > > > >
              > > > >
              > > > >
              > > > >----- Original Message -----
              > > > >From: "Gustavo" <gustavo@...>
              > > > >To: <seattlerobotics@yahoogroups.com>
              > > > >Sent: Tuesday, August 05, 2003 5:10 AM
              > > > >Subject: [SeattleRobotics] Motors and Encoders
              > > > >
              > > > >
              > > > > > Hello,
              > > > > >
              > > > > > I'm looking for a suitable encoder, and motor (it doesn't
              > > > > necessarily have to be a single package) for a micromouse robot. I
              have
              > > > > tried to salvage optical encoders from computer mice, but I can't
              seem
              > >to
              > > > > get them coupled on the axles. I have thought of printing out an
              encoder
              > > > > on a transparency, but then it would be difficult to align, and it
              would
              > > > > probably bend. I have also though of just printing out an encoder
              with
              > > > > the sectors alternating black and white, but then I face two
              problems,
              > > > > the lack of resolution, and precision, and the lighting conditions
              that
              > > > > might affect the reading of the sensor. I don't need a lot of
              > >resolution,
              > > > > but at least around 30. as for the actual sensor, I don't need a
              > > > > quadrature because the direction that the motor is going is not
              needed
              > >(I
              > > > > control the motors, I know the direction I set them).
              > > > > >
              > > > > > As for the motors, I haven't tried servos, and I don't want to
              use
              > > > > them for rotations, if I do incorporate servos, it will be for
              rotating
              > >a
              > > > > "head" with various sensors. I need something with speed (I would
              like
              > > > > the mouse to go at about 1 meter per second, or maybe faster)
              > > > > > The maximum size for the robot is 16.8 cm. (~6.6 in) squared
              > > > > because the passage way is 18 cm. (~7 in) and the wall width is 1.2
              cm
              > > > > (~.47 in). But I would the like the robot to be smaller than that to
              be
              > > > > able to maneuver easily. The width of the robot is going to have to
              be
              > >to
              > > > > be is around 11 cm (4.4 in) if the base is a square, if it is a
              circle,
              > > > > it could be slightly bigger. so the maximum length of the motors
              would
              > > > > have to be 5.5 cm (2.2 in) because I don't want to use and external
              gear
              > > > > train, I cant put the motors side by side, and if the encoder is on
              the
              > > > > shaft of the motor then I can't put and other gears because of the
              > > > > spacing in between the gear (each gear can rotate freely a few
              degrees).
              > > > > The motor should have a gear train, even if it is outside in a box.
              > > > > > I have also though about the possibility of using stepper
              motors.
              > > > > This way I wouldn't need to use the encoder, unless the wheel slips,
              or
              > > > > the stepper motor looses some steps. But stepper motors are hard to
              > >mount
              > > > > because most of them have a pinion gear on there shaft, and the ones
              > >used
              > > > > in old 5 1/4 drives weight too much. But it is something that I am
              > >considering.
              > > > > > I have tried to use a Lego design (I've built Lego robots for
              2
              > > > > years with the Mindstorm line of kits, I've stopped now) but I
              couldn't
              > > > > get it to be small enough the Lego gear motors are really good, but
              they
              > > > > also go slow, and I had a difficult time mounting the encoder, so I
              > >tried
              > > > > to use a gear, but the design wouldn't be small enough. I then
              though
              > > > > about the Lego rotation sensor, but its signal is analog, there are
              4
              > > > > different voltage level, at for different parts of the cycle, but
              then
              > > > > this would require either a port on the ADC, or 4 comparators (the
              339
              > > > > chip) and it would waste 4 I/O pins. AND it would be inaccurate for
              > >high
              > > > > speeds.
              > > > > >
              > > > > >
              > > > > >
              > > > > > BTW. this is for my 7th grade science project. Idea of the
              project
              > > > > is to identify which algorithm is more efficient, and faster in
              solving
              > > > > the maze. I may make the use a different maze then the ones used in
              > > > > micromouse compition (maybe less cells, or the beginning and end
              > >location
              > > > > is different). I chose this idea because it is more of a programming
              > > > > project, then a hardware project, and I am better at software than
              > > > > hardware, I don't really have any mechanical skills, which is why I
              want
              > > > > to keep the actual motor hardware simple. My dad can help me with
              the
              > > > > mechanical aspects of the project.
              > > > > >
              > > > > > These are some micromouse links if you want more information
              > > > > >
              > > > > > http://micromouse.cannock.ac.uk/
              > > > > >
              > > > > > http://micromouse.cs.rhbnc.ac.uk/
              > > > > >
              > > > > >
              http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
              > > > > >
              > > > > > http://fused.org/projects/
              > > > > >
              > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
              > > > > >
              > > > > > http://www.ece.ucdavis.edu/umouse/
              > > > > >
              > > > > >
              > > > > > And help is appreciated
              > > > > >
              > > > > > Rgds,
              > > > > > Gustavo
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > >
              > > > > > [Non-text portions of this message have been removed]
              > > > > >
              > > > > >
              > > > > > Visit the SRS Website at http://www.seattlerobotics.org
              > > > > >
              > > > > > To unsubscribe from this group, send an email to:
              > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
              > > > > >
              > > > > >
              > > > > > Your use of Yahoo! Groups is subject to
              > >http://docs.yahoo.com/info/terms/
              > > > > >
              > > > > >
              > > > >
              > > > >[Non-text portions of this message have been removed]
              > > > >
              > > > >
              > > > >Visit the SRS Website at http://www.seattlerobotics.org
              > > > >
              > > > >To unsubscribe from this group, send an email to:
              > > > >SeattleRobotics-unsubscribe@yahoogroups.com
              > > > >
              > > > >
              > > > >Your use of Yahoo! Groups is subject to
              http://docs.yahoo.com/info/terms/
              > > >
              > > >
              > > > Visit the SRS Website at http://www.seattlerobotics.org
              > > >
              > > > To unsubscribe from this group, send an email to:
              > > > SeattleRobotics-unsubscribe@yahoogroups.com
              > > >
              > > >
              > > > Your use of Yahoo! Groups is subject to
              http://docs.yahoo.com/info/terms/
              > > >
              > > >
              > > >
              > >
              > >
              > >Visit the SRS Website at http://www.seattlerobotics.org
              > >
              > >To unsubscribe from this group, send an email to:
              > >SeattleRobotics-unsubscribe@yahoogroups.com
              > >
              > >
              > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
              >
              >
              >
              > Visit the SRS Website at http://www.seattlerobotics.org
              >
              > To unsubscribe from this group, send an email to:
              > SeattleRobotics-unsubscribe@yahoogroups.com
              >
              >
              > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
              >
              >
              >
            • Tom Capon
              If you make the wheels as big as possible and the motors actually have some torque, it should speed in up quite a bit. Of course, if you aren t satisfied with
              Message 6 of 15 , Aug 6, 2003
                If you make the wheels as big as possible and the motors actually have some
                torque, it should speed in up quite a bit. Of course, if you aren't
                satisfied with that, you could always get custom-built miniature gearhead
                motors for $400 each. And if it has good traction and is very light, you
                should be able to go pretty fast. Then there is the other aspect of
                things: that unless you have really super-precision encoders or super-fast
                optical rangefinding, it's going to be very difficult to control something
                going that fast, even with a super-fast processor.

                At 03:40 AM 8/6/2003 -0400, Gustavo wrote:
                >The pager motors are very fast, but they have near to no torque.
                >I took a look at the Solorbotics website before, and the motors seem very
                >good, but I don't think they are fast enough.
                >I don't understand about what you mean that I don't know the direction the
                >motor is going. If you apply power to it in a certain polarity it will go on
                >way, and if you reverse the polarity it will rotate the other way (Not true
                >for AC motors, or brushless fan motors).
                >----- Original Message -----
                >From: "Jim McBride" <mcbride7@...>
                >To: <seattlerobotics@yahoogroups.com>
                >Sent: Tuesday, August 05, 2003 10:27 PM
                >Subject: Re: [SeattleRobotics] Motors and Encoders
                >
                >
                > > You may want to explore BEAM applications for small motors.
                >Solarbotics.com
                > > has a lot of useful miniature items.
                > > http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
                > >
                > > Jim
                > >
                > > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
                > > > How do the other micromice (can't think of a better word!) achieve
                >this
                > > >size and speed?
                > > >I am currently learning how to use the ATMega16 / 32 because of its
                >speed,
                > > >but I am also learning how to program the Rabbitcore 2000 from
                > > >http://www.rabbitsemiconductor.com/. It has a lot of RAM , and program
                > > >memory, and has four serial ports. If I do use both of these processors
                >then
                > > >the Rabbit would be the master, and the ATMega would be the slave. I am
                > > >planning in using the ATMega for controlling the motors, and reading the
                > > >encoder and reading the other sensors (It has a built in ADC).
                > > >
                > > >
                > > >
                > > >----- Original Message -----
                > > >From: "Tom Capon" <robot@...>
                > > >To: <seattlerobotics@yahoogroups.com>
                > > >Sent: Tuesday, August 05, 2003 11:24 AM
                > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                > > >
                > > >
                > > > >
                > > > > Well, I think you're going to have a tough time making something that
                > > >small
                > > > > and that fast. You might want to look into pager motors, they can be
                > > >found
                > > > > most any surplus house. Assuming you're running this thing on a flat
                > > > > table-top-like surface, you might even want to use a mouse as the body
                >of
                > > > > the robot. There are sites that explain how to hack a mouse to get
                >the
                > > > > encoder signals right out of the board without have to add your own
                > > >drivers
                > > > > and stuff. The only problem with the pager motors is that the are
                > > > > fast. You would have to get about four of them maybe and put the
                > > > > (computer) mouse on wheels. Just slip a bit of rubber tubing (really
                > > >small
                > > > > diameter) over the motor shaft and you've got a fairly good tire that
                >will
                > > > > gear it down a lot just by being small. If you get an optical mouse,
                > > > > (under $20, probably) there would be much less friction and it would
                >be
                > > > > easier to control. there is a link to a site on how to hack an
                >optical
                > > > > mouse for encoder-like outputs on my site,
                > > > > www.destructonet.org/tom/robotics . BTW, what microcontroller are you
                > > >using?
                > > > >
                > > > >
                > > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
                > > > > >Sorry, Maybe I didn't make myself clear when I said :
                > > > > >
                > > > > >I don't want to use and external gear train, I cant put the motors
                >side
                > > >by
                > > > > >side...
                > > > > >
                > > > > >I meant that the motors have to be like this:
                > > > > > _______ ______
                > > > > >shaft | | | |shaft
                > > > > >--------|motor1 | |motor2 |--------
                > > > > > |______| |______|
                > > > > >
                > > > > >
                > > > > >and not like:
                > > > > >
                > > > > >
                > > > > >___|___ ___|___
                > > > > >| | | |
                > > > > >|Motor1| |Motor2 |
                > > > > >|______| |______ |
                > > > > >
                > > > > >
                > > > > >or:
                > > > > >
                > > > > > |Gear
                > > > > > | ________
                > > > > >\/ | |
                > > > > >*-------|Motor1 |
                > > > > > |_______ |
                > > > > >* ________ * bigger gear
                > > > > >^ | |
                > > > > >| |Motor2 |----------*
                > > > > >| |_______ | ^
                > > > > >| gear
                > > > > >bigger gear
                > > > > >
                > > > > > the bigger gear is connected to the shaft.
                > > > > >
                > > > > >
                > > > > >(Forgive me for the horrible ASCII art.)
                > > > > >
                > > > > >
                > > > > >
                > > > > >----- Original Message -----
                > > > > >From: "Gustavo" <gustavo@...>
                > > > > >To: <seattlerobotics@yahoogroups.com>
                > > > > >Sent: Tuesday, August 05, 2003 5:10 AM
                > > > > >Subject: [SeattleRobotics] Motors and Encoders
                > > > > >
                > > > > >
                > > > > > > Hello,
                > > > > > >
                > > > > > > I'm looking for a suitable encoder, and motor (it doesn't
                > > > > > necessarily have to be a single package) for a micromouse robot. I
                >have
                > > > > > tried to salvage optical encoders from computer mice, but I can't
                >seem
                > > >to
                > > > > > get them coupled on the axles. I have thought of printing out an
                >encoder
                > > > > > on a transparency, but then it would be difficult to align, and it
                >would
                > > > > > probably bend. I have also though of just printing out an encoder
                >with
                > > > > > the sectors alternating black and white, but then I face two
                >problems,
                > > > > > the lack of resolution, and precision, and the lighting conditions
                >that
                > > > > > might affect the reading of the sensor. I don't need a lot of
                > > >resolution,
                > > > > > but at least around 30. as for the actual sensor, I don't need a
                > > > > > quadrature because the direction that the motor is going is not
                >needed
                > > >(I
                > > > > > control the motors, I know the direction I set them).
                > > > > > >
                > > > > > > As for the motors, I haven't tried servos, and I don't want to
                >use
                > > > > > them for rotations, if I do incorporate servos, it will be for
                >rotating
                > > >a
                > > > > > "head" with various sensors. I need something with speed (I would
                >like
                > > > > > the mouse to go at about 1 meter per second, or maybe faster)
                > > > > > > The maximum size for the robot is 16.8 cm. (~6.6 in) squared
                > > > > > because the passage way is 18 cm. (~7 in) and the wall width is 1.2
                >cm
                > > > > > (~.47 in). But I would the like the robot to be smaller than that to
                >be
                > > > > > able to maneuver easily. The width of the robot is going to have to
                >be
                > > >to
                > > > > > be is around 11 cm (4.4 in) if the base is a square, if it is a
                >circle,
                > > > > > it could be slightly bigger. so the maximum length of the motors
                >would
                > > > > > have to be 5.5 cm (2.2 in) because I don't want to use and external
                >gear
                > > > > > train, I cant put the motors side by side, and if the encoder is on
                >the
                > > > > > shaft of the motor then I can't put and other gears because of the
                > > > > > spacing in between the gear (each gear can rotate freely a few
                >degrees).
                > > > > > The motor should have a gear train, even if it is outside in a box.
                > > > > > > I have also though about the possibility of using stepper
                >motors.
                > > > > > This way I wouldn't need to use the encoder, unless the wheel slips,
                >or
                > > > > > the stepper motor looses some steps. But stepper motors are hard to
                > > >mount
                > > > > > because most of them have a pinion gear on there shaft, and the ones
                > > >used
                > > > > > in old 5 1/4 drives weight too much. But it is something that I am
                > > >considering.
                > > > > > > I have tried to use a Lego design (I've built Lego robots for
                >2
                > > > > > years with the Mindstorm line of kits, I've stopped now) but I
                >couldn't
                > > > > > get it to be small enough the Lego gear motors are really good, but
                >they
                > > > > > also go slow, and I had a difficult time mounting the encoder, so I
                > > >tried
                > > > > > to use a gear, but the design wouldn't be small enough. I then
                >though
                > > > > > about the Lego rotation sensor, but its signal is analog, there are
                >4
                > > > > > different voltage level, at for different parts of the cycle, but
                >then
                > > > > > this would require either a port on the ADC, or 4 comparators (the
                >339
                > > > > > chip) and it would waste 4 I/O pins. AND it would be inaccurate for
                > > >high
                > > > > > speeds.
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > > BTW. this is for my 7th grade science project. Idea of the
                >project
                > > > > > is to identify which algorithm is more efficient, and faster in
                >solving
                > > > > > the maze. I may make the use a different maze then the ones used in
                > > > > > micromouse compition (maybe less cells, or the beginning and end
                > > >location
                > > > > > is different). I chose this idea because it is more of a programming
                > > > > > project, then a hardware project, and I am better at software than
                > > > > > hardware, I don't really have any mechanical skills, which is why I
                >want
                > > > > > to keep the actual motor hardware simple. My dad can help me with
                >the
                > > > > > mechanical aspects of the project.
                > > > > > >
                > > > > > > These are some micromouse links if you want more information
                > > > > > >
                > > > > > > http://micromouse.cannock.ac.uk/
                > > > > > >
                > > > > > > http://micromouse.cs.rhbnc.ac.uk/
                > > > > > >
                > > > > > >
                >http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
                > > > > > >
                > > > > > > http://fused.org/projects/
                > > > > > >
                > > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
                > > > > > >
                > > > > > > http://www.ece.ucdavis.edu/umouse/
                > > > > > >
                > > > > > >
                > > > > > > And help is appreciated
                > > > > > >
                > > > > > > Rgds,
                > > > > > > Gustavo
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > >
                > > > > > > [Non-text portions of this message have been removed]
                > > > > > >
                > > > > > >
                > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                > > > > > >
                > > > > > > To unsubscribe from this group, send an email to:
                > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                > > > > > >
                > > > > > >
                > > > > > > Your use of Yahoo! Groups is subject to
                > > >http://docs.yahoo.com/info/terms/
                > > > > > >
                > > > > > >
                > > > > >
                > > > > >[Non-text portions of this message have been removed]
                > > > > >
                > > > > >
                > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                > > > > >
                > > > > >To unsubscribe from this group, send an email to:
                > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                > > > > >
                > > > > >
                > > > > >Your use of Yahoo! Groups is subject to
                >http://docs.yahoo.com/info/terms/
                > > > >
                > > > >
                > > > > Visit the SRS Website at http://www.seattlerobotics.org
                > > > >
                > > > > To unsubscribe from this group, send an email to:
                > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                > > > >
                > > > >
                > > > > Your use of Yahoo! Groups is subject to
                >http://docs.yahoo.com/info/terms/
                > > > >
                > > > >
                > > > >
                > > >
                > > >
                > > >Visit the SRS Website at http://www.seattlerobotics.org
                > > >
                > > >To unsubscribe from this group, send an email to:
                > > >SeattleRobotics-unsubscribe@yahoogroups.com
                > > >
                > > >
                > > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                > >
                > >
                > >
                > > Visit the SRS Website at http://www.seattlerobotics.org
                > >
                > > To unsubscribe from this group, send an email to:
                > > SeattleRobotics-unsubscribe@yahoogroups.com
                > >
                > >
                > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                > >
                > >
                > >
                >
                >
                >Visit the SRS Website at http://www.seattlerobotics.org
                >
                >To unsubscribe from this group, send an email to:
                >SeattleRobotics-unsubscribe@yahoogroups.com
                >
                >
                >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
              • Gustavo
                $800 dollars just for motors is way out of my budget :-( If I_use the solarbotics gearmotor with their wheel, my robot will be able to go 1.3 cm a second.
                Message 7 of 15 , Aug 6, 2003
                  $800 dollars just for motors is way out of my budget :-(
                  If I_use the solarbotics' gearmotor with their wheel, my robot will be able to go 1.3 cm a second. which is really slow

                  I am still wondering how the other micromouse achieve this speed, see the links below for movies to see how fast they really go, well some of them.
                  ----- Original Message -----
                  From: "Tom Capon" <robot@...>
                  To: "Gustavo" <gustavo@...>; <seattlerobotics@yahoogroups.com>
                  Sent: Wednesday, August 06, 2003 9:09 AM
                  Subject: Re: [SeattleRobotics] Motors and Encoders


                  > If you make the wheels as big as possible and the motors actually have some
                  > torque, it should speed in up quite a bit. Of course, if you aren't
                  > satisfied with that, you could always get custom-built miniature gearhead
                  > motors for $400 each. And if it has good traction and is very light, you
                  > should be able to go pretty fast. Then there is the other aspect of
                  > things: that unless you have really super-precision encoders or super-fast
                  > optical rangefinding, it's going to be very difficult to control something
                  > going that fast, even with a super-fast processor.
                  >
                  > At 03:40 AM 8/6/2003 -0400, Gustavo wrote:
                  > >The pager motors are very fast, but they have near to no torque.
                  > >I took a look at the Solorbotics website before, and the motors seem very
                  > >good, but I don't think they are fast enough.
                  > >I don't understand about what you mean that I don't know the direction the
                  > >motor is going. If you apply power to it in a certain polarity it will go on
                  > >way, and if you reverse the polarity it will rotate the other way (Not true
                  > >for AC motors, or brushless fan motors).
                  > >----- Original Message -----
                  > >From: "Jim McBride" <mcbride7@...>
                  > >To: <seattlerobotics@yahoogroups.com>
                  > >Sent: Tuesday, August 05, 2003 10:27 PM
                  > >Subject: Re: [SeattleRobotics] Motors and Encoders
                  > >
                  > >
                  > > > You may want to explore BEAM applications for small motors.
                  > >Solarbotics.com
                  > > > has a lot of useful miniature items.
                  > > > http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
                  > > >
                  > > > Jim
                  > > >
                  > > > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
                  > > > > How do the other micromice (can't think of a better word!) achieve
                  > >this
                  > > > >size and speed?
                  > > > >I am currently learning how to use the ATMega16 / 32 because of its
                  > >speed,
                  > > > >but I am also learning how to program the Rabbitcore 2000 from
                  > > > >http://www.rabbitsemiconductor.com/. It has a lot of RAM , and program
                  > > > >memory, and has four serial ports. If I do use both of these processors
                  > >then
                  > > > >the Rabbit would be the master, and the ATMega would be the slave. I am
                  > > > >planning in using the ATMega for controlling the motors, and reading the
                  > > > >encoder and reading the other sensors (It has a built in ADC).
                  > > > >
                  > > > >
                  > > > >
                  > > > >----- Original Message -----
                  > > > >From: "Tom Capon" <robot@...>
                  > > > >To: <seattlerobotics@yahoogroups.com>
                  > > > >Sent: Tuesday, August 05, 2003 11:24 AM
                  > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                  > > > >
                  > > > >
                  > > > > >
                  > > > > > Well, I think you're going to have a tough time making something that
                  > > > >small
                  > > > > > and that fast. You might want to look into pager motors, they can be
                  > > > >found
                  > > > > > most any surplus house. Assuming you're running this thing on a flat
                  > > > > > table-top-like surface, you might even want to use a mouse as the body
                  > >of
                  > > > > > the robot. There are sites that explain how to hack a mouse to get
                  > >the
                  > > > > > encoder signals right out of the board without have to add your own
                  > > > >drivers
                  > > > > > and stuff. The only problem with the pager motors is that the are
                  > > > > > fast. You would have to get about four of them maybe and put the
                  > > > > > (computer) mouse on wheels. Just slip a bit of rubber tubing (really
                  > > > >small
                  > > > > > diameter) over the motor shaft and you've got a fairly good tire that
                  > >will
                  > > > > > gear it down a lot just by being small. If you get an optical mouse,
                  > > > > > (under $20, probably) there would be much less friction and it would
                  > >be
                  > > > > > easier to control. there is a link to a site on how to hack an
                  > >optical
                  > > > > > mouse for encoder-like outputs on my site,
                  > > > > > www.destructonet.org/tom/robotics . BTW, what microcontroller are you
                  > > > >using?
                  > > > > >
                  > > > > >
                  > > > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
                  > > > > > >Sorry, Maybe I didn't make myself clear when I said :
                  > > > > > >
                  > > > > > >I don't want to use and external gear train, I cant put the motors
                  > >side
                  > > > >by
                  > > > > > >side...
                  > > > > > >
                  > > > > > >I meant that the motors have to be like this:
                  > > > > > > _______ ______
                  > > > > > >shaft | | | |shaft
                  > > > > > >--------|motor1 | |motor2 |--------
                  > > > > > > |______| |______|
                  > > > > > >
                  > > > > > >
                  > > > > > >and not like:
                  > > > > > >
                  > > > > > >
                  > > > > > >___|___ ___|___
                  > > > > > >| | | |
                  > > > > > >|Motor1| |Motor2 |
                  > > > > > >|______| |______ |
                  > > > > > >
                  > > > > > >
                  > > > > > >or:
                  > > > > > >
                  > > > > > > |Gear
                  > > > > > > | ________
                  > > > > > >\/ | |
                  > > > > > >*-------|Motor1 |
                  > > > > > > |_______ |
                  > > > > > >* ________ * bigger gear
                  > > > > > >^ | |
                  > > > > > >| |Motor2 |----------*
                  > > > > > >| |_______ | ^
                  > > > > > >| gear
                  > > > > > >bigger gear
                  > > > > > >
                  > > > > > > the bigger gear is connected to the shaft.
                  > > > > > >
                  > > > > > >
                  > > > > > >(Forgive me for the horrible ASCII art.)
                  > > > > > >
                  > > > > > >
                  > > > > > >
                  > > > > > >----- Original Message -----
                  > > > > > >From: "Gustavo" <gustavo@...>
                  > > > > > >To: <seattlerobotics@yahoogroups.com>
                  > > > > > >Sent: Tuesday, August 05, 2003 5:10 AM
                  > > > > > >Subject: [SeattleRobotics] Motors and Encoders
                  > > > > > >
                  > > > > > >
                  > > > > > > > Hello,
                  > > > > > > >
                  > > > > > > > I'm looking for a suitable encoder, and motor (it doesn't
                  > > > > > > necessarily have to be a single package) for a micromouse robot. I
                  > >have
                  > > > > > > tried to salvage optical encoders from computer mice, but I can't
                  > >seem
                  > > > >to
                  > > > > > > get them coupled on the axles. I have thought of printing out an
                  > >encoder
                  > > > > > > on a transparency, but then it would be difficult to align, and it
                  > >would
                  > > > > > > probably bend. I have also though of just printing out an encoder
                  > >with
                  > > > > > > the sectors alternating black and white, but then I face two
                  > >problems,
                  > > > > > > the lack of resolution, and precision, and the lighting conditions
                  > >that
                  > > > > > > might affect the reading of the sensor. I don't need a lot of
                  > > > >resolution,
                  > > > > > > but at least around 30. as for the actual sensor, I don't need a
                  > > > > > > quadrature because the direction that the motor is going is not
                  > >needed
                  > > > >(I
                  > > > > > > control the motors, I know the direction I set them).
                  > > > > > > >
                  > > > > > > > As for the motors, I haven't tried servos, and I don't want to
                  > >use
                  > > > > > > them for rotations, if I do incorporate servos, it will be for
                  > >rotating
                  > > > >a
                  > > > > > > "head" with various sensors. I need something with speed (I would
                  > >like
                  > > > > > > the mouse to go at about 1 meter per second, or maybe faster)
                  > > > > > > > The maximum size for the robot is 16.8 cm. (~6.6 in) squared
                  > > > > > > because the passage way is 18 cm. (~7 in) and the wall width is 1.2
                  > >cm
                  > > > > > > (~.47 in). But I would the like the robot to be smaller than that to
                  > >be
                  > > > > > > able to maneuver easily. The width of the robot is going to have to
                  > >be
                  > > > >to
                  > > > > > > be is around 11 cm (4.4 in) if the base is a square, if it is a
                  > >circle,
                  > > > > > > it could be slightly bigger. so the maximum length of the motors
                  > >would
                  > > > > > > have to be 5.5 cm (2.2 in) because I don't want to use and external
                  > >gear
                  > > > > > > train, I cant put the motors side by side, and if the encoder is on
                  > >the
                  > > > > > > shaft of the motor then I can't put and other gears because of the
                  > > > > > > spacing in between the gear (each gear can rotate freely a few
                  > >degrees).
                  > > > > > > The motor should have a gear train, even if it is outside in a box.
                  > > > > > > > I have also though about the possibility of using stepper
                  > >motors.
                  > > > > > > This way I wouldn't need to use the encoder, unless the wheel slips,
                  > >or
                  > > > > > > the stepper motor looses some steps. But stepper motors are hard to
                  > > > >mount
                  > > > > > > because most of them have a pinion gear on there shaft, and the ones
                  > > > >used
                  > > > > > > in old 5 1/4 drives weight too much. But it is something that I am
                  > > > >considering.
                  > > > > > > > I have tried to use a Lego design (I've built Lego robots for
                  > >2
                  > > > > > > years with the Mindstorm line of kits, I've stopped now) but I
                  > >couldn't
                  > > > > > > get it to be small enough the Lego gear motors are really good, but
                  > >they
                  > > > > > > also go slow, and I had a difficult time mounting the encoder, so I
                  > > > >tried
                  > > > > > > to use a gear, but the design wouldn't be small enough. I then
                  > >though
                  > > > > > > about the Lego rotation sensor, but its signal is analog, there are
                  > >4
                  > > > > > > different voltage level, at for different parts of the cycle, but
                  > >then
                  > > > > > > this would require either a port on the ADC, or 4 comparators (the
                  > >339
                  > > > > > > chip) and it would waste 4 I/O pins. AND it would be inaccurate for
                  > > > >high
                  > > > > > > speeds.
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > > BTW. this is for my 7th grade science project. Idea of the
                  > >project
                  > > > > > > is to identify which algorithm is more efficient, and faster in
                  > >solving
                  > > > > > > the maze. I may make the use a different maze then the ones used in
                  > > > > > > micromouse compition (maybe less cells, or the beginning and end
                  > > > >location
                  > > > > > > is different). I chose this idea because it is more of a programming
                  > > > > > > project, then a hardware project, and I am better at software than
                  > > > > > > hardware, I don't really have any mechanical skills, which is why I
                  > >want
                  > > > > > > to keep the actual motor hardware simple. My dad can help me with
                  > >the
                  > > > > > > mechanical aspects of the project.
                  > > > > > > >
                  > > > > > > > These are some micromouse links if you want more information
                  > > > > > > >
                  > > > > > > > http://micromouse.cannock.ac.uk/
                  > > > > > > >
                  > > > > > > > http://micromouse.cs.rhbnc.ac.uk/
                  > > > > > > >
                  > > > > > > >
                  > >http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
                  > > > > > > >
                  > > > > > > > http://fused.org/projects/
                  > > > > > > >
                  > > > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
                  > > > > > > >
                  > > > > > > > http://www.ece.ucdavis.edu/umouse/
                  > > > > > > >
                  > > > > > > >
                  > > > > > > > And help is appreciated
                  > > > > > > >
                  > > > > > > > Rgds,
                  > > > > > > > Gustavo
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > >
                  > > > > > > > [Non-text portions of this message have been removed]
                  > > > > > > >
                  > > > > > > >
                  > > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                  > > > > > > >
                  > > > > > > > To unsubscribe from this group, send an email to:
                  > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                  > > > > > > >
                  > > > > > > >
                  > > > > > > > Your use of Yahoo! Groups is subject to
                  > > > >http://docs.yahoo.com/info/terms/
                  > > > > > > >
                  > > > > > > >
                  > > > > > >
                  > > > > > >[Non-text portions of this message have been removed]
                  > > > > > >
                  > > > > > >
                  > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                  > > > > > >
                  > > > > > >To unsubscribe from this group, send an email to:
                  > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                  > > > > > >
                  > > > > > >
                  > > > > > >Your use of Yahoo! Groups is subject to
                  > >http://docs.yahoo.com/info/terms/
                  > > > > >
                  > > > > >
                  > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                  > > > > >
                  > > > > > To unsubscribe from this group, send an email to:
                  > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                  > > > > >
                  > > > > >
                  > > > > > Your use of Yahoo! Groups is subject to
                  > >http://docs.yahoo.com/info/terms/
                  > > > > >
                  > > > > >
                  > > > > >
                  > > > >
                  > > > >
                  > > > >Visit the SRS Website at http://www.seattlerobotics.org
                  > > > >
                  > > > >To unsubscribe from this group, send an email to:
                  > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                  > > > >
                  > > > >
                  > > > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                  > > >
                  > > >
                  > > >
                  > > > Visit the SRS Website at http://www.seattlerobotics.org
                  > > >
                  > > > To unsubscribe from this group, send an email to:
                  > > > SeattleRobotics-unsubscribe@yahoogroups.com
                  > > >
                  > > >
                  > > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                  > > >
                  > > >
                  > > >
                  > >
                  > >
                  > >Visit the SRS Website at http://www.seattlerobotics.org
                  > >
                  > >To unsubscribe from this group, send an email to:
                  > >SeattleRobotics-unsubscribe@yahoogroups.com
                  > >
                  > >
                  > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                  >
                  >

                  [Non-text portions of this message have been removed]
                • Tom Capon
                  From the looks of it, they must use really small gearboxes. how big is the solarbotics wheel?
                  Message 8 of 15 , Aug 6, 2003
                    From the looks of it, they must use really small gearboxes. how big is
                    the solarbotics' wheel?

                    At 02:45 PM 8/6/2003 -0400, Gustavo wrote:
                    >$800 dollars just for motors is way out of my budget :-(
                    >If I_use the solarbotics' gearmotor with their wheel, my robot will be
                    >able to go 1.3 cm a second. which is really slow
                    >
                    >I am still wondering how the other micromouse achieve this speed, see the
                    >links below for movies to see how fast they really go, well some of them.
                    >----- Original Message -----
                    >From: "Tom Capon" <robot@...>
                    >To: "Gustavo" <gustavo@...>; <seattlerobotics@yahoogroups.com>
                    >Sent: Wednesday, August 06, 2003 9:09 AM
                    >Subject: Re: [SeattleRobotics] Motors and Encoders
                    >
                    >
                    > > If you make the wheels as big as possible and the motors actually have
                    > some
                    > > torque, it should speed in up quite a bit. Of course, if you aren't
                    > > satisfied with that, you could always get custom-built miniature gearhead
                    > > motors for $400 each. And if it has good traction and is very light, you
                    > > should be able to go pretty fast. Then there is the other aspect of
                    > > things: that unless you have really super-precision encoders or
                    > super-fast
                    > > optical rangefinding, it's going to be very difficult to control
                    > something
                    > > going that fast, even with a super-fast processor.
                    > >
                    > > At 03:40 AM 8/6/2003 -0400, Gustavo wrote:
                    > > >The pager motors are very fast, but they have near to no torque.
                    > > >I took a look at the Solorbotics website before, and the motors seem very
                    > > >good, but I don't think they are fast enough.
                    > > >I don't understand about what you mean that I don't know the direction the
                    > > >motor is going. If you apply power to it in a certain polarity it will
                    > go on
                    > > >way, and if you reverse the polarity it will rotate the other way (Not
                    > true
                    > > >for AC motors, or brushless fan motors).
                    > > >----- Original Message -----
                    > > >From: "Jim McBride" <mcbride7@...>
                    > > >To: <seattlerobotics@yahoogroups.com>
                    > > >Sent: Tuesday, August 05, 2003 10:27 PM
                    > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                    > > >
                    > > >
                    > > > > You may want to explore BEAM applications for small motors.
                    > > >Solarbotics.com
                    > > > > has a lot of useful miniature items.
                    > > > > http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
                    > > > >
                    > > > > Jim
                    > > > >
                    > > > > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
                    > > > > > How do the other micromice (can't think of a better word!) achieve
                    > > >this
                    > > > > >size and speed?
                    > > > > >I am currently learning how to use the ATMega16 / 32 because of its
                    > > >speed,
                    > > > > >but I am also learning how to program the Rabbitcore 2000 from
                    > > > > >http://www.rabbitsemiconductor.com/. It has a lot of RAM , and program
                    > > > > >memory, and has four serial ports. If I do use both of these
                    > processors
                    > > >then
                    > > > > >the Rabbit would be the master, and the ATMega would be the slave.
                    > I am
                    > > > > >planning in using the ATMega for controlling the motors, and
                    > reading the
                    > > > > >encoder and reading the other sensors (It has a built in ADC).
                    > > > > >
                    > > > > >
                    > > > > >
                    > > > > >----- Original Message -----
                    > > > > >From: "Tom Capon" <robot@...>
                    > > > > >To: <seattlerobotics@yahoogroups.com>
                    > > > > >Sent: Tuesday, August 05, 2003 11:24 AM
                    > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                    > > > > >
                    > > > > >
                    > > > > > >
                    > > > > > > Well, I think you're going to have a tough time making
                    > something that
                    > > > > >small
                    > > > > > > and that fast. You might want to look into pager motors, they
                    > can be
                    > > > > >found
                    > > > > > > most any surplus house. Assuming you're running this thing on
                    > a flat
                    > > > > > > table-top-like surface, you might even want to use a mouse as
                    > the body
                    > > >of
                    > > > > > > the robot. There are sites that explain how to hack a mouse to get
                    > > >the
                    > > > > > > encoder signals right out of the board without have to add your own
                    > > > > >drivers
                    > > > > > > and stuff. The only problem with the pager motors is that the are
                    > > > > > > fast. You would have to get about four of them maybe and put the
                    > > > > > > (computer) mouse on wheels. Just slip a bit of rubber tubing
                    > (really
                    > > > > >small
                    > > > > > > diameter) over the motor shaft and you've got a fairly good
                    > tire that
                    > > >will
                    > > > > > > gear it down a lot just by being small. If you get an optical
                    > mouse,
                    > > > > > > (under $20, probably) there would be much less friction and it
                    > would
                    > > >be
                    > > > > > > easier to control. there is a link to a site on how to hack an
                    > > >optical
                    > > > > > > mouse for encoder-like outputs on my site,
                    > > > > > > www.destructonet.org/tom/robotics . BTW, what microcontroller
                    > are you
                    > > > > >using?
                    > > > > > >
                    > > > > > >
                    > > > > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
                    > > > > > > >Sorry, Maybe I didn't make myself clear when I said :
                    > > > > > > >
                    > > > > > > >I don't want to use and external gear train, I cant put the motors
                    > > >side
                    > > > > >by
                    > > > > > > >side...
                    > > > > > > >
                    > > > > > > >I meant that the motors have to be like this:
                    > > > > > > > _______ ______
                    > > > > > > >shaft | | | |shaft
                    > > > > > > >--------|motor1 | |motor2 |--------
                    > > > > > > > |______| |______|
                    > > > > > > >
                    > > > > > > >
                    > > > > > > >and not like:
                    > > > > > > >
                    > > > > > > >
                    > > > > > > >___|___ ___|___
                    > > > > > > >| | | |
                    > > > > > > >|Motor1| |Motor2 |
                    > > > > > > >|______| |______ |
                    > > > > > > >
                    > > > > > > >
                    > > > > > > >or:
                    > > > > > > >
                    > > > > > > > |Gear
                    > > > > > > > | ________
                    > > > > > > >\/ | |
                    > > > > > > >*-------|Motor1 |
                    > > > > > > > |_______ |
                    > > > > > > >* ________ * bigger gear
                    > > > > > > >^ | |
                    > > > > > > >| |Motor2 |----------*
                    > > > > > > >| |_______ | ^
                    > > > > > > >| gear
                    > > > > > > >bigger gear
                    > > > > > > >
                    > > > > > > > the bigger gear is connected to the shaft.
                    > > > > > > >
                    > > > > > > >
                    > > > > > > >(Forgive me for the horrible ASCII art.)
                    > > > > > > >
                    > > > > > > >
                    > > > > > > >
                    > > > > > > >----- Original Message -----
                    > > > > > > >From: "Gustavo" <gustavo@...>
                    > > > > > > >To: <seattlerobotics@yahoogroups.com>
                    > > > > > > >Sent: Tuesday, August 05, 2003 5:10 AM
                    > > > > > > >Subject: [SeattleRobotics] Motors and Encoders
                    > > > > > > >
                    > > > > > > >
                    > > > > > > > > Hello,
                    > > > > > > > >
                    > > > > > > > > I'm looking for a suitable encoder, and motor (it doesn't
                    > > > > > > > necessarily have to be a single package) for a micromouse
                    > robot. I
                    > > >have
                    > > > > > > > tried to salvage optical encoders from computer mice, but I can't
                    > > >seem
                    > > > > >to
                    > > > > > > > get them coupled on the axles. I have thought of printing out an
                    > > >encoder
                    > > > > > > > on a transparency, but then it would be difficult to align,
                    > and it
                    > > >would
                    > > > > > > > probably bend. I have also though of just printing out an encoder
                    > > >with
                    > > > > > > > the sectors alternating black and white, but then I face two
                    > > >problems,
                    > > > > > > > the lack of resolution, and precision, and the lighting
                    > conditions
                    > > >that
                    > > > > > > > might affect the reading of the sensor. I don't need a lot of
                    > > > > >resolution,
                    > > > > > > > but at least around 30. as for the actual sensor, I don't need a
                    > > > > > > > quadrature because the direction that the motor is going is not
                    > > >needed
                    > > > > >(I
                    > > > > > > > control the motors, I know the direction I set them).
                    > > > > > > > >
                    > > > > > > > > As for the motors, I haven't tried servos, and I don't
                    > want to
                    > > >use
                    > > > > > > > them for rotations, if I do incorporate servos, it will be for
                    > > >rotating
                    > > > > >a
                    > > > > > > > "head" with various sensors. I need something with speed (I would
                    > > >like
                    > > > > > > > the mouse to go at about 1 meter per second, or maybe faster)
                    > > > > > > > > The maximum size for the robot is 16.8 cm. (~6.6 in)
                    > squared
                    > > > > > > > because the passage way is 18 cm. (~7 in) and the wall width
                    > is 1.2
                    > > >cm
                    > > > > > > > (~.47 in). But I would the like the robot to be smaller than
                    > that to
                    > > >be
                    > > > > > > > able to maneuver easily. The width of the robot is going to
                    > have to
                    > > >be
                    > > > > >to
                    > > > > > > > be is around 11 cm (4.4 in) if the base is a square, if it is a
                    > > >circle,
                    > > > > > > > it could be slightly bigger. so the maximum length of the motors
                    > > >would
                    > > > > > > > have to be 5.5 cm (2.2 in) because I don't want to use and
                    > external
                    > > >gear
                    > > > > > > > train, I cant put the motors side by side, and if the encoder
                    > is on
                    > > >the
                    > > > > > > > shaft of the motor then I can't put and other gears because
                    > of the
                    > > > > > > > spacing in between the gear (each gear can rotate freely a few
                    > > >degrees).
                    > > > > > > > The motor should have a gear train, even if it is outside in
                    > a box.
                    > > > > > > > > I have also though about the possibility of using stepper
                    > > >motors.
                    > > > > > > > This way I wouldn't need to use the encoder, unless the wheel
                    > slips,
                    > > >or
                    > > > > > > > the stepper motor looses some steps. But stepper motors are
                    > hard to
                    > > > > >mount
                    > > > > > > > because most of them have a pinion gear on there shaft, and
                    > the ones
                    > > > > >used
                    > > > > > > > in old 5 1/4 drives weight too much. But it is something that
                    > I am
                    > > > > >considering.
                    > > > > > > > > I have tried to use a Lego design (I've built Lego
                    > robots for
                    > > >2
                    > > > > > > > years with the Mindstorm line of kits, I've stopped now) but I
                    > > >couldn't
                    > > > > > > > get it to be small enough the Lego gear motors are really
                    > good, but
                    > > >they
                    > > > > > > > also go slow, and I had a difficult time mounting the
                    > encoder, so I
                    > > > > >tried
                    > > > > > > > to use a gear, but the design wouldn't be small enough. I then
                    > > >though
                    > > > > > > > about the Lego rotation sensor, but its signal is analog,
                    > there are
                    > > >4
                    > > > > > > > different voltage level, at for different parts of the cycle, but
                    > > >then
                    > > > > > > > this would require either a port on the ADC, or 4 comparators
                    > (the
                    > > >339
                    > > > > > > > chip) and it would waste 4 I/O pins. AND it would be
                    > inaccurate for
                    > > > > >high
                    > > > > > > > speeds.
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > > BTW. this is for my 7th grade science project. Idea of the
                    > > >project
                    > > > > > > > is to identify which algorithm is more efficient, and faster in
                    > > >solving
                    > > > > > > > the maze. I may make the use a different maze then the ones
                    > used in
                    > > > > > > > micromouse compition (maybe less cells, or the beginning and end
                    > > > > >location
                    > > > > > > > is different). I chose this idea because it is more of a
                    > programming
                    > > > > > > > project, then a hardware project, and I am better at software
                    > than
                    > > > > > > > hardware, I don't really have any mechanical skills, which is
                    > why I
                    > > >want
                    > > > > > > > to keep the actual motor hardware simple. My dad can help me with
                    > > >the
                    > > > > > > > mechanical aspects of the project.
                    > > > > > > > >
                    > > > > > > > > These are some micromouse links if you want more
                    > information
                    > > > > > > > >
                    > > > > > > > > http://micromouse.cannock.ac.uk/
                    > > > > > > > >
                    > > > > > > > > http://micromouse.cs.rhbnc.ac.uk/
                    > > > > > > > >
                    > > > > > > > >
                    > > >http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
                    > > > > > > > >
                    > > > > > > > > http://fused.org/projects/
                    > > > > > > > >
                    > > > > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
                    > > > > > > > >
                    > > > > > > > > http://www.ece.ucdavis.edu/umouse/
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > > And help is appreciated
                    > > > > > > > >
                    > > > > > > > > Rgds,
                    > > > > > > > > Gustavo
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > > [Non-text portions of this message have been removed]
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                    > > > > > > > >
                    > > > > > > > > To unsubscribe from this group, send an email to:
                    > > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > > > Your use of Yahoo! Groups is subject to
                    > > > > >http://docs.yahoo.com/info/terms/
                    > > > > > > > >
                    > > > > > > > >
                    > > > > > > >
                    > > > > > > >[Non-text portions of this message have been removed]
                    > > > > > > >
                    > > > > > > >
                    > > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                    > > > > > > >
                    > > > > > > >To unsubscribe from this group, send an email to:
                    > > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                    > > > > > > >
                    > > > > > > >
                    > > > > > > >Your use of Yahoo! Groups is subject to
                    > > >http://docs.yahoo.com/info/terms/
                    > > > > > >
                    > > > > > >
                    > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                    > > > > > >
                    > > > > > > To unsubscribe from this group, send an email to:
                    > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                    > > > > > >
                    > > > > > >
                    > > > > > > Your use of Yahoo! Groups is subject to
                    > > >http://docs.yahoo.com/info/terms/
                    > > > > > >
                    > > > > > >
                    > > > > > >
                    > > > > >
                    > > > > >
                    > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                    > > > > >
                    > > > > >To unsubscribe from this group, send an email to:
                    > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                    > > > > >
                    > > > > >
                    > > > > >Your use of Yahoo! Groups is subject to
                    > http://docs.yahoo.com/info/terms/
                    > > > >
                    > > > >
                    > > > >
                    > > > > Visit the SRS Website at http://www.seattlerobotics.org
                    > > > >
                    > > > > To unsubscribe from this group, send an email to:
                    > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                    > > > >
                    > > > >
                    > > > > Your use of Yahoo! Groups is subject to
                    > http://docs.yahoo.com/info/terms/
                    > > > >
                    > > > >
                    > > > >
                    > > >
                    > > >
                    > > >Visit the SRS Website at http://www.seattlerobotics.org
                    > > >
                    > > >To unsubscribe from this group, send an email to:
                    > > >SeattleRobotics-unsubscribe@yahoogroups.com
                    > > >
                    > > >
                    > > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                    > >
                    > >
                    >
                    >[Non-text portions of this message have been removed]
                    >
                    >
                    >Visit the SRS Website at http://www.seattlerobotics.org
                    >
                    >To unsubscribe from this group, send an email to:
                    >SeattleRobotics-unsubscribe@yahoogroups.com
                    >
                    >
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                  • Tom Capon
                    I just did some checking and if you can make do with larger wheels, they have another gearmotor that will take you at about 20 cm per second with a 6.5 cm
                    Message 9 of 15 , Aug 6, 2003
                      I just did some checking and if you can make do with larger wheels, they
                      have another gearmotor that will take you at about 20 cm per second with a
                      6.5 cm diameter wheel. there are several other motors and wheels on that
                      page, just select "all" entries per page.

                      At 02:45 PM 8/6/2003 -0400, Gustavo wrote:
                      >$800 dollars just for motors is way out of my budget :-(
                      >If I_use the solarbotics' gearmotor with their wheel, my robot will be
                      >able to go 1.3 cm a second. which is really slow
                      >
                      >I am still wondering how the other micromouse achieve this speed, see the
                      >links below for movies to see how fast they really go, well some of them.
                      >----- Original Message -----
                      >From: "Tom Capon" <robot@...>
                      >To: "Gustavo" <gustavo@...>; <seattlerobotics@yahoogroups.com>
                      >Sent: Wednesday, August 06, 2003 9:09 AM
                      >Subject: Re: [SeattleRobotics] Motors and Encoders
                      >
                      >
                      > > If you make the wheels as big as possible and the motors actually have
                      > some
                      > > torque, it should speed in up quite a bit. Of course, if you aren't
                      > > satisfied with that, you could always get custom-built miniature gearhead
                      > > motors for $400 each. And if it has good traction and is very light, you
                      > > should be able to go pretty fast. Then there is the other aspect of
                      > > things: that unless you have really super-precision encoders or
                      > super-fast
                      > > optical rangefinding, it's going to be very difficult to control
                      > something
                      > > going that fast, even with a super-fast processor.
                      > >
                      > > At 03:40 AM 8/6/2003 -0400, Gustavo wrote:
                      > > >The pager motors are very fast, but they have near to no torque.
                      > > >I took a look at the Solorbotics website before, and the motors seem very
                      > > >good, but I don't think they are fast enough.
                      > > >I don't understand about what you mean that I don't know the direction the
                      > > >motor is going. If you apply power to it in a certain polarity it will
                      > go on
                      > > >way, and if you reverse the polarity it will rotate the other way (Not
                      > true
                      > > >for AC motors, or brushless fan motors).
                      > > >----- Original Message -----
                      > > >From: "Jim McBride" <mcbride7@...>
                      > > >To: <seattlerobotics@yahoogroups.com>
                      > > >Sent: Tuesday, August 05, 2003 10:27 PM
                      > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                      > > >
                      > > >
                      > > > > You may want to explore BEAM applications for small motors.
                      > > >Solarbotics.com
                      > > > > has a lot of useful miniature items.
                      > > > > http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
                      > > > >
                      > > > > Jim
                      > > > >
                      > > > > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
                      > > > > > How do the other micromice (can't think of a better word!) achieve
                      > > >this
                      > > > > >size and speed?
                      > > > > >I am currently learning how to use the ATMega16 / 32 because of its
                      > > >speed,
                      > > > > >but I am also learning how to program the Rabbitcore 2000 from
                      > > > > >http://www.rabbitsemiconductor.com/. It has a lot of RAM , and program
                      > > > > >memory, and has four serial ports. If I do use both of these
                      > processors
                      > > >then
                      > > > > >the Rabbit would be the master, and the ATMega would be the slave.
                      > I am
                      > > > > >planning in using the ATMega for controlling the motors, and
                      > reading the
                      > > > > >encoder and reading the other sensors (It has a built in ADC).
                      > > > > >
                      > > > > >
                      > > > > >
                      > > > > >----- Original Message -----
                      > > > > >From: "Tom Capon" <robot@...>
                      > > > > >To: <seattlerobotics@yahoogroups.com>
                      > > > > >Sent: Tuesday, August 05, 2003 11:24 AM
                      > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                      > > > > >
                      > > > > >
                      > > > > > >
                      > > > > > > Well, I think you're going to have a tough time making
                      > something that
                      > > > > >small
                      > > > > > > and that fast. You might want to look into pager motors, they
                      > can be
                      > > > > >found
                      > > > > > > most any surplus house. Assuming you're running this thing on
                      > a flat
                      > > > > > > table-top-like surface, you might even want to use a mouse as
                      > the body
                      > > >of
                      > > > > > > the robot. There are sites that explain how to hack a mouse to get
                      > > >the
                      > > > > > > encoder signals right out of the board without have to add your own
                      > > > > >drivers
                      > > > > > > and stuff. The only problem with the pager motors is that the are
                      > > > > > > fast. You would have to get about four of them maybe and put the
                      > > > > > > (computer) mouse on wheels. Just slip a bit of rubber tubing
                      > (really
                      > > > > >small
                      > > > > > > diameter) over the motor shaft and you've got a fairly good
                      > tire that
                      > > >will
                      > > > > > > gear it down a lot just by being small. If you get an optical
                      > mouse,
                      > > > > > > (under $20, probably) there would be much less friction and it
                      > would
                      > > >be
                      > > > > > > easier to control. there is a link to a site on how to hack an
                      > > >optical
                      > > > > > > mouse for encoder-like outputs on my site,
                      > > > > > > www.destructonet.org/tom/robotics . BTW, what microcontroller
                      > are you
                      > > > > >using?
                      > > > > > >
                      > > > > > >
                      > > > > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
                      > > > > > > >Sorry, Maybe I didn't make myself clear when I said :
                      > > > > > > >
                      > > > > > > >I don't want to use and external gear train, I cant put the motors
                      > > >side
                      > > > > >by
                      > > > > > > >side...
                      > > > > > > >
                      > > > > > > >I meant that the motors have to be like this:
                      > > > > > > > _______ ______
                      > > > > > > >shaft | | | |shaft
                      > > > > > > >--------|motor1 | |motor2 |--------
                      > > > > > > > |______| |______|
                      > > > > > > >
                      > > > > > > >
                      > > > > > > >and not like:
                      > > > > > > >
                      > > > > > > >
                      > > > > > > >___|___ ___|___
                      > > > > > > >| | | |
                      > > > > > > >|Motor1| |Motor2 |
                      > > > > > > >|______| |______ |
                      > > > > > > >
                      > > > > > > >
                      > > > > > > >or:
                      > > > > > > >
                      > > > > > > > |Gear
                      > > > > > > > | ________
                      > > > > > > >\/ | |
                      > > > > > > >*-------|Motor1 |
                      > > > > > > > |_______ |
                      > > > > > > >* ________ * bigger gear
                      > > > > > > >^ | |
                      > > > > > > >| |Motor2 |----------*
                      > > > > > > >| |_______ | ^
                      > > > > > > >| gear
                      > > > > > > >bigger gear
                      > > > > > > >
                      > > > > > > > the bigger gear is connected to the shaft.
                      > > > > > > >
                      > > > > > > >
                      > > > > > > >(Forgive me for the horrible ASCII art.)
                      > > > > > > >
                      > > > > > > >
                      > > > > > > >
                      > > > > > > >----- Original Message -----
                      > > > > > > >From: "Gustavo" <gustavo@...>
                      > > > > > > >To: <seattlerobotics@yahoogroups.com>
                      > > > > > > >Sent: Tuesday, August 05, 2003 5:10 AM
                      > > > > > > >Subject: [SeattleRobotics] Motors and Encoders
                      > > > > > > >
                      > > > > > > >
                      > > > > > > > > Hello,
                      > > > > > > > >
                      > > > > > > > > I'm looking for a suitable encoder, and motor (it doesn't
                      > > > > > > > necessarily have to be a single package) for a micromouse
                      > robot. I
                      > > >have
                      > > > > > > > tried to salvage optical encoders from computer mice, but I can't
                      > > >seem
                      > > > > >to
                      > > > > > > > get them coupled on the axles. I have thought of printing out an
                      > > >encoder
                      > > > > > > > on a transparency, but then it would be difficult to align,
                      > and it
                      > > >would
                      > > > > > > > probably bend. I have also though of just printing out an encoder
                      > > >with
                      > > > > > > > the sectors alternating black and white, but then I face two
                      > > >problems,
                      > > > > > > > the lack of resolution, and precision, and the lighting
                      > conditions
                      > > >that
                      > > > > > > > might affect the reading of the sensor. I don't need a lot of
                      > > > > >resolution,
                      > > > > > > > but at least around 30. as for the actual sensor, I don't need a
                      > > > > > > > quadrature because the direction that the motor is going is not
                      > > >needed
                      > > > > >(I
                      > > > > > > > control the motors, I know the direction I set them).
                      > > > > > > > >
                      > > > > > > > > As for the motors, I haven't tried servos, and I don't
                      > want to
                      > > >use
                      > > > > > > > them for rotations, if I do incorporate servos, it will be for
                      > > >rotating
                      > > > > >a
                      > > > > > > > "head" with various sensors. I need something with speed (I would
                      > > >like
                      > > > > > > > the mouse to go at about 1 meter per second, or maybe faster)
                      > > > > > > > > The maximum size for the robot is 16.8 cm. (~6.6 in)
                      > squared
                      > > > > > > > because the passage way is 18 cm. (~7 in) and the wall width
                      > is 1.2
                      > > >cm
                      > > > > > > > (~.47 in). But I would the like the robot to be smaller than
                      > that to
                      > > >be
                      > > > > > > > able to maneuver easily. The width of the robot is going to
                      > have to
                      > > >be
                      > > > > >to
                      > > > > > > > be is around 11 cm (4.4 in) if the base is a square, if it is a
                      > > >circle,
                      > > > > > > > it could be slightly bigger. so the maximum length of the motors
                      > > >would
                      > > > > > > > have to be 5.5 cm (2.2 in) because I don't want to use and
                      > external
                      > > >gear
                      > > > > > > > train, I cant put the motors side by side, and if the encoder
                      > is on
                      > > >the
                      > > > > > > > shaft of the motor then I can't put and other gears because
                      > of the
                      > > > > > > > spacing in between the gear (each gear can rotate freely a few
                      > > >degrees).
                      > > > > > > > The motor should have a gear train, even if it is outside in
                      > a box.
                      > > > > > > > > I have also though about the possibility of using stepper
                      > > >motors.
                      > > > > > > > This way I wouldn't need to use the encoder, unless the wheel
                      > slips,
                      > > >or
                      > > > > > > > the stepper motor looses some steps. But stepper motors are
                      > hard to
                      > > > > >mount
                      > > > > > > > because most of them have a pinion gear on there shaft, and
                      > the ones
                      > > > > >used
                      > > > > > > > in old 5 1/4 drives weight too much. But it is something that
                      > I am
                      > > > > >considering.
                      > > > > > > > > I have tried to use a Lego design (I've built Lego
                      > robots for
                      > > >2
                      > > > > > > > years with the Mindstorm line of kits, I've stopped now) but I
                      > > >couldn't
                      > > > > > > > get it to be small enough the Lego gear motors are really
                      > good, but
                      > > >they
                      > > > > > > > also go slow, and I had a difficult time mounting the
                      > encoder, so I
                      > > > > >tried
                      > > > > > > > to use a gear, but the design wouldn't be small enough. I then
                      > > >though
                      > > > > > > > about the Lego rotation sensor, but its signal is analog,
                      > there are
                      > > >4
                      > > > > > > > different voltage level, at for different parts of the cycle, but
                      > > >then
                      > > > > > > > this would require either a port on the ADC, or 4 comparators
                      > (the
                      > > >339
                      > > > > > > > chip) and it would waste 4 I/O pins. AND it would be
                      > inaccurate for
                      > > > > >high
                      > > > > > > > speeds.
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > > BTW. this is for my 7th grade science project. Idea of the
                      > > >project
                      > > > > > > > is to identify which algorithm is more efficient, and faster in
                      > > >solving
                      > > > > > > > the maze. I may make the use a different maze then the ones
                      > used in
                      > > > > > > > micromouse compition (maybe less cells, or the beginning and end
                      > > > > >location
                      > > > > > > > is different). I chose this idea because it is more of a
                      > programming
                      > > > > > > > project, then a hardware project, and I am better at software
                      > than
                      > > > > > > > hardware, I don't really have any mechanical skills, which is
                      > why I
                      > > >want
                      > > > > > > > to keep the actual motor hardware simple. My dad can help me with
                      > > >the
                      > > > > > > > mechanical aspects of the project.
                      > > > > > > > >
                      > > > > > > > > These are some micromouse links if you want more
                      > information
                      > > > > > > > >
                      > > > > > > > > http://micromouse.cannock.ac.uk/
                      > > > > > > > >
                      > > > > > > > > http://micromouse.cs.rhbnc.ac.uk/
                      > > > > > > > >
                      > > > > > > > >
                      > > >http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
                      > > > > > > > >
                      > > > > > > > > http://fused.org/projects/
                      > > > > > > > >
                      > > > > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
                      > > > > > > > >
                      > > > > > > > > http://www.ece.ucdavis.edu/umouse/
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > > And help is appreciated
                      > > > > > > > >
                      > > > > > > > > Rgds,
                      > > > > > > > > Gustavo
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > > [Non-text portions of this message have been removed]
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                      > > > > > > > >
                      > > > > > > > > To unsubscribe from this group, send an email to:
                      > > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > > > Your use of Yahoo! Groups is subject to
                      > > > > >http://docs.yahoo.com/info/terms/
                      > > > > > > > >
                      > > > > > > > >
                      > > > > > > >
                      > > > > > > >[Non-text portions of this message have been removed]
                      > > > > > > >
                      > > > > > > >
                      > > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                      > > > > > > >
                      > > > > > > >To unsubscribe from this group, send an email to:
                      > > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                      > > > > > > >
                      > > > > > > >
                      > > > > > > >Your use of Yahoo! Groups is subject to
                      > > >http://docs.yahoo.com/info/terms/
                      > > > > > >
                      > > > > > >
                      > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                      > > > > > >
                      > > > > > > To unsubscribe from this group, send an email to:
                      > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                      > > > > > >
                      > > > > > >
                      > > > > > > Your use of Yahoo! Groups is subject to
                      > > >http://docs.yahoo.com/info/terms/
                      > > > > > >
                      > > > > > >
                      > > > > > >
                      > > > > >
                      > > > > >
                      > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                      > > > > >
                      > > > > >To unsubscribe from this group, send an email to:
                      > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                      > > > > >
                      > > > > >
                      > > > > >Your use of Yahoo! Groups is subject to
                      > http://docs.yahoo.com/info/terms/
                      > > > >
                      > > > >
                      > > > >
                      > > > > Visit the SRS Website at http://www.seattlerobotics.org
                      > > > >
                      > > > > To unsubscribe from this group, send an email to:
                      > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                      > > > >
                      > > > >
                      > > > > Your use of Yahoo! Groups is subject to
                      > http://docs.yahoo.com/info/terms/
                      > > > >
                      > > > >
                      > > > >
                      > > >
                      > > >
                      > > >Visit the SRS Website at http://www.seattlerobotics.org
                      > > >
                      > > >To unsubscribe from this group, send an email to:
                      > > >SeattleRobotics-unsubscribe@yahoogroups.com
                      > > >
                      > > >
                      > > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                      > >
                      > >
                      >
                      >[Non-text portions of this message have been removed]
                      >
                      >
                      >Visit the SRS Website at http://www.seattlerobotics.org
                      >
                      >To unsubscribe from this group, send an email to:
                      >SeattleRobotics-unsubscribe@yahoogroups.com
                      >
                      >
                      >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                    • Gustavo
                      I totally forgot about the modifying option, thanks a lot everybody for all of the help :-) ... From: Tom Capon To:
                      Message 10 of 15 , Aug 7, 2003
                        I totally forgot about the modifying option, thanks a lot everybody for all
                        of the help :-)
                        ----- Original Message -----
                        From: "Tom Capon" <robot@...>
                        To: <seattlerobotics@yahoogroups.com>
                        Sent: Wednesday, August 06, 2003 5:35 PM
                        Subject: Re: [SeattleRobotics] Motors and Encoders


                        > I just did some checking and if you can make do with larger wheels, they
                        > have another gearmotor that will take you at about 20 cm per second with a
                        > 6.5 cm diameter wheel. there are several other motors and wheels on that
                        > page, just select "all" entries per page.
                        >
                        > At 02:45 PM 8/6/2003 -0400, Gustavo wrote:
                        > >$800 dollars just for motors is way out of my budget :-(
                        > >If I_use the solarbotics' gearmotor with their wheel, my robot will be
                        > >able to go 1.3 cm a second. which is really slow
                        > >
                        > >I am still wondering how the other micromouse achieve this speed, see the
                        > >links below for movies to see how fast they really go, well some of them.
                        > >----- Original Message -----
                        > >From: "Tom Capon" <robot@...>
                        > >To: "Gustavo" <gustavo@...>; <seattlerobotics@yahoogroups.com>
                        > >Sent: Wednesday, August 06, 2003 9:09 AM
                        > >Subject: Re: [SeattleRobotics] Motors and Encoders
                        > >
                        > >
                        > > > If you make the wheels as big as possible and the motors actually have
                        > > some
                        > > > torque, it should speed in up quite a bit. Of course, if you aren't
                        > > > satisfied with that, you could always get custom-built miniature
                        gearhead
                        > > > motors for $400 each. And if it has good traction and is very light,
                        you
                        > > > should be able to go pretty fast. Then there is the other aspect of
                        > > > things: that unless you have really super-precision encoders or
                        > > super-fast
                        > > > optical rangefinding, it's going to be very difficult to control
                        > > something
                        > > > going that fast, even with a super-fast processor.
                        > > >
                        > > > At 03:40 AM 8/6/2003 -0400, Gustavo wrote:
                        > > > >The pager motors are very fast, but they have near to no torque.
                        > > > >I took a look at the Solorbotics website before, and the motors seem
                        very
                        > > > >good, but I don't think they are fast enough.
                        > > > >I don't understand about what you mean that I don't know the
                        direction the
                        > > > >motor is going. If you apply power to it in a certain polarity it
                        will
                        > > go on
                        > > > >way, and if you reverse the polarity it will rotate the other way
                        (Not
                        > > true
                        > > > >for AC motors, or brushless fan motors).
                        > > > >----- Original Message -----
                        > > > >From: "Jim McBride" <mcbride7@...>
                        > > > >To: <seattlerobotics@yahoogroups.com>
                        > > > >Sent: Tuesday, August 05, 2003 10:27 PM
                        > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                        > > > >
                        > > > >
                        > > > > > You may want to explore BEAM applications for small motors.
                        > > > >Solarbotics.com
                        > > > > > has a lot of useful miniature items.
                        > > > > >
                        http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
                        > > > > >
                        > > > > > Jim
                        > > > > >
                        > > > > > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
                        > > > > > > How do the other micromice (can't think of a better word!)
                        achieve
                        > > > >this
                        > > > > > >size and speed?
                        > > > > > >I am currently learning how to use the ATMega16 / 32 because of
                        its
                        > > > >speed,
                        > > > > > >but I am also learning how to program the Rabbitcore 2000 from
                        > > > > > >http://www.rabbitsemiconductor.com/. It has a lot of RAM , and
                        program
                        > > > > > >memory, and has four serial ports. If I do use both of these
                        > > processors
                        > > > >then
                        > > > > > >the Rabbit would be the master, and the ATMega would be the
                        slave.
                        > > I am
                        > > > > > >planning in using the ATMega for controlling the motors, and
                        > > reading the
                        > > > > > >encoder and reading the other sensors (It has a built in ADC).
                        > > > > > >
                        > > > > > >
                        > > > > > >
                        > > > > > >----- Original Message -----
                        > > > > > >From: "Tom Capon" <robot@...>
                        > > > > > >To: <seattlerobotics@yahoogroups.com>
                        > > > > > >Sent: Tuesday, August 05, 2003 11:24 AM
                        > > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                        > > > > > >
                        > > > > > >
                        > > > > > > >
                        > > > > > > > Well, I think you're going to have a tough time making
                        > > something that
                        > > > > > >small
                        > > > > > > > and that fast. You might want to look into pager motors, they
                        > > can be
                        > > > > > >found
                        > > > > > > > most any surplus house. Assuming you're running this thing on
                        > > a flat
                        > > > > > > > table-top-like surface, you might even want to use a mouse as
                        > > the body
                        > > > >of
                        > > > > > > > the robot. There are sites that explain how to hack a mouse
                        to get
                        > > > >the
                        > > > > > > > encoder signals right out of the board without have to add
                        your own
                        > > > > > >drivers
                        > > > > > > > and stuff. The only problem with the pager motors is that the
                        are
                        > > > > > > > fast. You would have to get about four of them maybe and put
                        the
                        > > > > > > > (computer) mouse on wheels. Just slip a bit of rubber tubing
                        > > (really
                        > > > > > >small
                        > > > > > > > diameter) over the motor shaft and you've got a fairly good
                        > > tire that
                        > > > >will
                        > > > > > > > gear it down a lot just by being small. If you get an optical
                        > > mouse,
                        > > > > > > > (under $20, probably) there would be much less friction and
                        it
                        > > would
                        > > > >be
                        > > > > > > > easier to control. there is a link to a site on how to hack
                        an
                        > > > >optical
                        > > > > > > > mouse for encoder-like outputs on my site,
                        > > > > > > > www.destructonet.org/tom/robotics . BTW, what microcontroller
                        > > are you
                        > > > > > >using?
                        > > > > > > >
                        > > > > > > >
                        > > > > > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
                        > > > > > > > >Sorry, Maybe I didn't make myself clear when I said :
                        > > > > > > > >
                        > > > > > > > >I don't want to use and external gear train, I cant put the
                        motors
                        > > > >side
                        > > > > > >by
                        > > > > > > > >side...
                        > > > > > > > >
                        > > > > > > > >I meant that the motors have to be like this:
                        > > > > > > > > _______ ______
                        > > > > > > > >shaft | | | |shaft
                        > > > > > > > >--------|motor1 | |motor2 |--------
                        > > > > > > > > |______| |______|
                        > > > > > > > >
                        > > > > > > > >
                        > > > > > > > >and not like:
                        > > > > > > > >
                        > > > > > > > >
                        > > > > > > > >___|___ ___|___
                        > > > > > > > >| | | |
                        > > > > > > > >|Motor1| |Motor2 |
                        > > > > > > > >|______| |______ |
                        > > > > > > > >
                        > > > > > > > >
                        > > > > > > > >or:
                        > > > > > > > >
                        > > > > > > > > |Gear
                        > > > > > > > > | ________
                        > > > > > > > >\/ | |
                        > > > > > > > >*-------|Motor1 |
                        > > > > > > > > |_______ |
                        > > > > > > > >* ________ * bigger gear
                        > > > > > > > >^ | |
                        > > > > > > > >| |Motor2 |----------*
                        > > > > > > > >| |_______ | ^
                        > > > > > > > >| gear
                        > > > > > > > >bigger gear
                        > > > > > > > >
                        > > > > > > > > the bigger gear is connected to the shaft.
                        > > > > > > > >
                        > > > > > > > >
                        > > > > > > > >(Forgive me for the horrible ASCII art.)
                        > > > > > > > >
                        > > > > > > > >
                        > > > > > > > >
                        > > > > > > > >----- Original Message -----
                        > > > > > > > >From: "Gustavo" <gustavo@...>
                        > > > > > > > >To: <seattlerobotics@yahoogroups.com>
                        > > > > > > > >Sent: Tuesday, August 05, 2003 5:10 AM
                        > > > > > > > >Subject: [SeattleRobotics] Motors and Encoders
                        > > > > > > > >
                        > > > > > > > >
                        > > > > > > > > > Hello,
                        > > > > > > > > >
                        > > > > > > > > > I'm looking for a suitable encoder, and motor (it
                        doesn't
                        > > > > > > > > necessarily have to be a single package) for a micromouse
                        > > robot. I
                        > > > >have
                        > > > > > > > > tried to salvage optical encoders from computer mice, but I
                        can't
                        > > > >seem
                        > > > > > >to
                        > > > > > > > > get them coupled on the axles. I have thought of printing
                        out an
                        > > > >encoder
                        > > > > > > > > on a transparency, but then it would be difficult to align,
                        > > and it
                        > > > >would
                        > > > > > > > > probably bend. I have also though of just printing out an
                        encoder
                        > > > >with
                        > > > > > > > > the sectors alternating black and white, but then I face two
                        > > > >problems,
                        > > > > > > > > the lack of resolution, and precision, and the lighting
                        > > conditions
                        > > > >that
                        > > > > > > > > might affect the reading of the sensor. I don't need a lot
                        of
                        > > > > > >resolution,
                        > > > > > > > > but at least around 30. as for the actual sensor, I don't
                        need a
                        > > > > > > > > quadrature because the direction that the motor is going is
                        not
                        > > > >needed
                        > > > > > >(I
                        > > > > > > > > control the motors, I know the direction I set them).
                        > > > > > > > > >
                        > > > > > > > > > As for the motors, I haven't tried servos, and I don't
                        > > want to
                        > > > >use
                        > > > > > > > > them for rotations, if I do incorporate servos, it will be
                        for
                        > > > >rotating
                        > > > > > >a
                        > > > > > > > > "head" with various sensors. I need something with speed (I
                        would
                        > > > >like
                        > > > > > > > > the mouse to go at about 1 meter per second, or maybe
                        faster)
                        > > > > > > > > > The maximum size for the robot is 16.8 cm. (~6.6 in)
                        > > squared
                        > > > > > > > > because the passage way is 18 cm. (~7 in) and the wall width
                        > > is 1.2
                        > > > >cm
                        > > > > > > > > (~.47 in). But I would the like the robot to be smaller than
                        > > that to
                        > > > >be
                        > > > > > > > > able to maneuver easily. The width of the robot is going to
                        > > have to
                        > > > >be
                        > > > > > >to
                        > > > > > > > > be is around 11 cm (4.4 in) if the base is a square, if it
                        is a
                        > > > >circle,
                        > > > > > > > > it could be slightly bigger. so the maximum length of the
                        motors
                        > > > >would
                        > > > > > > > > have to be 5.5 cm (2.2 in) because I don't want to use and
                        > > external
                        > > > >gear
                        > > > > > > > > train, I cant put the motors side by side, and if the
                        encoder
                        > > is on
                        > > > >the
                        > > > > > > > > shaft of the motor then I can't put and other gears because
                        > > of the
                        > > > > > > > > spacing in between the gear (each gear can rotate freely a
                        few
                        > > > >degrees).
                        > > > > > > > > The motor should have a gear train, even if it is outside in
                        > > a box.
                        > > > > > > > > > I have also though about the possibility of using
                        stepper
                        > > > >motors.
                        > > > > > > > > This way I wouldn't need to use the encoder, unless the
                        wheel
                        > > slips,
                        > > > >or
                        > > > > > > > > the stepper motor looses some steps. But stepper motors are
                        > > hard to
                        > > > > > >mount
                        > > > > > > > > because most of them have a pinion gear on there shaft, and
                        > > the ones
                        > > > > > >used
                        > > > > > > > > in old 5 1/4 drives weight too much. But it is something
                        that
                        > > I am
                        > > > > > >considering.
                        > > > > > > > > > I have tried to use a Lego design (I've built Lego
                        > > robots for
                        > > > >2
                        > > > > > > > > years with the Mindstorm line of kits, I've stopped now) but
                        I
                        > > > >couldn't
                        > > > > > > > > get it to be small enough the Lego gear motors are really
                        > > good, but
                        > > > >they
                        > > > > > > > > also go slow, and I had a difficult time mounting the
                        > > encoder, so I
                        > > > > > >tried
                        > > > > > > > > to use a gear, but the design wouldn't be small enough. I
                        then
                        > > > >though
                        > > > > > > > > about the Lego rotation sensor, but its signal is analog,
                        > > there are
                        > > > >4
                        > > > > > > > > different voltage level, at for different parts of the
                        cycle, but
                        > > > >then
                        > > > > > > > > this would require either a port on the ADC, or 4
                        comparators
                        > > (the
                        > > > >339
                        > > > > > > > > chip) and it would waste 4 I/O pins. AND it would be
                        > > inaccurate for
                        > > > > > >high
                        > > > > > > > > speeds.
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > > BTW. this is for my 7th grade science project. Idea of
                        the
                        > > > >project
                        > > > > > > > > is to identify which algorithm is more efficient, and faster
                        in
                        > > > >solving
                        > > > > > > > > the maze. I may make the use a different maze then the ones
                        > > used in
                        > > > > > > > > micromouse compition (maybe less cells, or the beginning and
                        end
                        > > > > > >location
                        > > > > > > > > is different). I chose this idea because it is more of a
                        > > programming
                        > > > > > > > > project, then a hardware project, and I am better at
                        software
                        > > than
                        > > > > > > > > hardware, I don't really have any mechanical skills, which
                        is
                        > > why I
                        > > > >want
                        > > > > > > > > to keep the actual motor hardware simple. My dad can help me
                        with
                        > > > >the
                        > > > > > > > > mechanical aspects of the project.
                        > > > > > > > > >
                        > > > > > > > > > These are some micromouse links if you want more
                        > > information
                        > > > > > > > > >
                        > > > > > > > > > http://micromouse.cannock.ac.uk/
                        > > > > > > > > >
                        > > > > > > > > > http://micromouse.cs.rhbnc.ac.uk/
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > >http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
                        > > > > > > > > >
                        > > > > > > > > > http://fused.org/projects/
                        > > > > > > > > >
                        > > > > > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
                        > > > > > > > > >
                        > > > > > > > > > http://www.ece.ucdavis.edu/umouse/
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > > And help is appreciated
                        > > > > > > > > >
                        > > > > > > > > > Rgds,
                        > > > > > > > > > Gustavo
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > > [Non-text portions of this message have been removed]
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                        > > > > > > > > >
                        > > > > > > > > > To unsubscribe from this group, send an email to:
                        > > > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > > > Your use of Yahoo! Groups is subject to
                        > > > > > >http://docs.yahoo.com/info/terms/
                        > > > > > > > > >
                        > > > > > > > > >
                        > > > > > > > >
                        > > > > > > > >[Non-text portions of this message have been removed]
                        > > > > > > > >
                        > > > > > > > >
                        > > > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                        > > > > > > > >
                        > > > > > > > >To unsubscribe from this group, send an email to:
                        > > > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                        > > > > > > > >
                        > > > > > > > >
                        > > > > > > > >Your use of Yahoo! Groups is subject to
                        > > > >http://docs.yahoo.com/info/terms/
                        > > > > > > >
                        > > > > > > >
                        > > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                        > > > > > > >
                        > > > > > > > To unsubscribe from this group, send an email to:
                        > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                        > > > > > > >
                        > > > > > > >
                        > > > > > > > Your use of Yahoo! Groups is subject to
                        > > > >http://docs.yahoo.com/info/terms/
                        > > > > > > >
                        > > > > > > >
                        > > > > > > >
                        > > > > > >
                        > > > > > >
                        > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                        > > > > > >
                        > > > > > >To unsubscribe from this group, send an email to:
                        > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                        > > > > > >
                        > > > > > >
                        > > > > > >Your use of Yahoo! Groups is subject to
                        > > http://docs.yahoo.com/info/terms/
                        > > > > >
                        > > > > >
                        > > > > >
                        > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                        > > > > >
                        > > > > > To unsubscribe from this group, send an email to:
                        > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                        > > > > >
                        > > > > >
                        > > > > > Your use of Yahoo! Groups is subject to
                        > > http://docs.yahoo.com/info/terms/
                        > > > > >
                        > > > > >
                        > > > > >
                        > > > >
                        > > > >
                        > > > >Visit the SRS Website at http://www.seattlerobotics.org
                        > > > >
                        > > > >To unsubscribe from this group, send an email to:
                        > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                        > > > >
                        > > > >
                        > > > >Your use of Yahoo! Groups is subject to
                        http://docs.yahoo.com/info/terms/
                        > > >
                        > > >
                        > >
                        > >[Non-text portions of this message have been removed]
                        > >
                        > >
                        > >Visit the SRS Website at http://www.seattlerobotics.org
                        > >
                        > >To unsubscribe from this group, send an email to:
                        > >SeattleRobotics-unsubscribe@yahoogroups.com
                        > >
                        > >
                        > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                        >
                        >
                        > Visit the SRS Website at http://www.seattlerobotics.org
                        >
                        > To unsubscribe from this group, send an email to:
                        > SeattleRobotics-unsubscribe@yahoogroups.com
                        >
                        >
                        > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
                        >
                        >
                        >
                      • Gustavo
                        now all I need if a good encoder disk ... From: Tom Capon To: Sent: Wednesday, August 06, 2003
                        Message 11 of 15 , Aug 7, 2003
                          now all I need if a good encoder disk

                          ----- Original Message -----
                          From: "Tom Capon" <robot@...>
                          To: <seattlerobotics@yahoogroups.com>
                          Sent: Wednesday, August 06, 2003 5:35 PM
                          Subject: Re: [SeattleRobotics] Motors and Encoders


                          > I just did some checking and if you can make do with larger wheels, they
                          > have another gearmotor that will take you at about 20 cm per second with a
                          > 6.5 cm diameter wheel. there are several other motors and wheels on that
                          > page, just select "all" entries per page.
                          >
                          > At 02:45 PM 8/6/2003 -0400, Gustavo wrote:
                          > >$800 dollars just for motors is way out of my budget :-(
                          > >If I_use the solarbotics' gearmotor with their wheel, my robot will be
                          > >able to go 1.3 cm a second. which is really slow
                          > >
                          > >I am still wondering how the other micromouse achieve this speed, see the
                          > >links below for movies to see how fast they really go, well some of them.
                          > >----- Original Message -----
                          > >From: "Tom Capon" <robot@...>
                          > >To: "Gustavo" <gustavo@...>; <seattlerobotics@yahoogroups.com>
                          > >Sent: Wednesday, August 06, 2003 9:09 AM
                          > >Subject: Re: [SeattleRobotics] Motors and Encoders
                          > >
                          > >
                          > > > If you make the wheels as big as possible and the motors actually have
                          > > some
                          > > > torque, it should speed in up quite a bit. Of course, if you aren't
                          > > > satisfied with that, you could always get custom-built miniature
                          gearhead
                          > > > motors for $400 each. And if it has good traction and is very light,
                          you
                          > > > should be able to go pretty fast. Then there is the other aspect of
                          > > > things: that unless you have really super-precision encoders or
                          > > super-fast
                          > > > optical rangefinding, it's going to be very difficult to control
                          > > something
                          > > > going that fast, even with a super-fast processor.
                          > > >
                          > > > At 03:40 AM 8/6/2003 -0400, Gustavo wrote:
                          > > > >The pager motors are very fast, but they have near to no torque.
                          > > > >I took a look at the Solorbotics website before, and the motors seem
                          very
                          > > > >good, but I don't think they are fast enough.
                          > > > >I don't understand about what you mean that I don't know the
                          direction the
                          > > > >motor is going. If you apply power to it in a certain polarity it
                          will
                          > > go on
                          > > > >way, and if you reverse the polarity it will rotate the other way
                          (Not
                          > > true
                          > > > >for AC motors, or brushless fan motors).
                          > > > >----- Original Message -----
                          > > > >From: "Jim McBride" <mcbride7@...>
                          > > > >To: <seattlerobotics@yahoogroups.com>
                          > > > >Sent: Tuesday, August 05, 2003 10:27 PM
                          > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                          > > > >
                          > > > >
                          > > > > > You may want to explore BEAM applications for small motors.
                          > > > >Solarbotics.com
                          > > > > > has a lot of useful miniature items.
                          > > > > >
                          http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
                          > > > > >
                          > > > > > Jim
                          > > > > >
                          > > > > > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
                          > > > > > > How do the other micromice (can't think of a better word!)
                          achieve
                          > > > >this
                          > > > > > >size and speed?
                          > > > > > >I am currently learning how to use the ATMega16 / 32 because of
                          its
                          > > > >speed,
                          > > > > > >but I am also learning how to program the Rabbitcore 2000 from
                          > > > > > >http://www.rabbitsemiconductor.com/. It has a lot of RAM , and
                          program
                          > > > > > >memory, and has four serial ports. If I do use both of these
                          > > processors
                          > > > >then
                          > > > > > >the Rabbit would be the master, and the ATMega would be the
                          slave.
                          > > I am
                          > > > > > >planning in using the ATMega for controlling the motors, and
                          > > reading the
                          > > > > > >encoder and reading the other sensors (It has a built in ADC).
                          > > > > > >
                          > > > > > >
                          > > > > > >
                          > > > > > >----- Original Message -----
                          > > > > > >From: "Tom Capon" <robot@...>
                          > > > > > >To: <seattlerobotics@yahoogroups.com>
                          > > > > > >Sent: Tuesday, August 05, 2003 11:24 AM
                          > > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                          > > > > > >
                          > > > > > >
                          > > > > > > >
                          > > > > > > > Well, I think you're going to have a tough time making
                          > > something that
                          > > > > > >small
                          > > > > > > > and that fast. You might want to look into pager motors, they
                          > > can be
                          > > > > > >found
                          > > > > > > > most any surplus house. Assuming you're running this thing on
                          > > a flat
                          > > > > > > > table-top-like surface, you might even want to use a mouse as
                          > > the body
                          > > > >of
                          > > > > > > > the robot. There are sites that explain how to hack a mouse
                          to get
                          > > > >the
                          > > > > > > > encoder signals right out of the board without have to add
                          your own
                          > > > > > >drivers
                          > > > > > > > and stuff. The only problem with the pager motors is that the
                          are
                          > > > > > > > fast. You would have to get about four of them maybe and put
                          the
                          > > > > > > > (computer) mouse on wheels. Just slip a bit of rubber tubing
                          > > (really
                          > > > > > >small
                          > > > > > > > diameter) over the motor shaft and you've got a fairly good
                          > > tire that
                          > > > >will
                          > > > > > > > gear it down a lot just by being small. If you get an optical
                          > > mouse,
                          > > > > > > > (under $20, probably) there would be much less friction and
                          it
                          > > would
                          > > > >be
                          > > > > > > > easier to control. there is a link to a site on how to hack
                          an
                          > > > >optical
                          > > > > > > > mouse for encoder-like outputs on my site,
                          > > > > > > > www.destructonet.org/tom/robotics . BTW, what microcontroller
                          > > are you
                          > > > > > >using?
                          > > > > > > >
                          > > > > > > >
                          > > > > > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
                          > > > > > > > >Sorry, Maybe I didn't make myself clear when I said :
                          > > > > > > > >
                          > > > > > > > >I don't want to use and external gear train, I cant put the
                          motors
                          > > > >side
                          > > > > > >by
                          > > > > > > > >side...
                          > > > > > > > >
                          > > > > > > > >I meant that the motors have to be like this:
                          > > > > > > > > _______ ______
                          > > > > > > > >shaft | | | |shaft
                          > > > > > > > >--------|motor1 | |motor2 |--------
                          > > > > > > > > |______| |______|
                          > > > > > > > >
                          > > > > > > > >
                          > > > > > > > >and not like:
                          > > > > > > > >
                          > > > > > > > >
                          > > > > > > > >___|___ ___|___
                          > > > > > > > >| | | |
                          > > > > > > > >|Motor1| |Motor2 |
                          > > > > > > > >|______| |______ |
                          > > > > > > > >
                          > > > > > > > >
                          > > > > > > > >or:
                          > > > > > > > >
                          > > > > > > > > |Gear
                          > > > > > > > > | ________
                          > > > > > > > >\/ | |
                          > > > > > > > >*-------|Motor1 |
                          > > > > > > > > |_______ |
                          > > > > > > > >* ________ * bigger gear
                          > > > > > > > >^ | |
                          > > > > > > > >| |Motor2 |----------*
                          > > > > > > > >| |_______ | ^
                          > > > > > > > >| gear
                          > > > > > > > >bigger gear
                          > > > > > > > >
                          > > > > > > > > the bigger gear is connected to the shaft.
                          > > > > > > > >
                          > > > > > > > >
                          > > > > > > > >(Forgive me for the horrible ASCII art.)
                          > > > > > > > >
                          > > > > > > > >
                          > > > > > > > >
                          > > > > > > > >----- Original Message -----
                          > > > > > > > >From: "Gustavo" <gustavo@...>
                          > > > > > > > >To: <seattlerobotics@yahoogroups.com>
                          > > > > > > > >Sent: Tuesday, August 05, 2003 5:10 AM
                          > > > > > > > >Subject: [SeattleRobotics] Motors and Encoders
                          > > > > > > > >
                          > > > > > > > >
                          > > > > > > > > > Hello,
                          > > > > > > > > >
                          > > > > > > > > > I'm looking for a suitable encoder, and motor (it
                          doesn't
                          > > > > > > > > necessarily have to be a single package) for a micromouse
                          > > robot. I
                          > > > >have
                          > > > > > > > > tried to salvage optical encoders from computer mice, but I
                          can't
                          > > > >seem
                          > > > > > >to
                          > > > > > > > > get them coupled on the axles. I have thought of printing
                          out an
                          > > > >encoder
                          > > > > > > > > on a transparency, but then it would be difficult to align,
                          > > and it
                          > > > >would
                          > > > > > > > > probably bend. I have also though of just printing out an
                          encoder
                          > > > >with
                          > > > > > > > > the sectors alternating black and white, but then I face two
                          > > > >problems,
                          > > > > > > > > the lack of resolution, and precision, and the lighting
                          > > conditions
                          > > > >that
                          > > > > > > > > might affect the reading of the sensor. I don't need a lot
                          of
                          > > > > > >resolution,
                          > > > > > > > > but at least around 30. as for the actual sensor, I don't
                          need a
                          > > > > > > > > quadrature because the direction that the motor is going is
                          not
                          > > > >needed
                          > > > > > >(I
                          > > > > > > > > control the motors, I know the direction I set them).
                          > > > > > > > > >
                          > > > > > > > > > As for the motors, I haven't tried servos, and I don't
                          > > want to
                          > > > >use
                          > > > > > > > > them for rotations, if I do incorporate servos, it will be
                          for
                          > > > >rotating
                          > > > > > >a
                          > > > > > > > > "head" with various sensors. I need something with speed (I
                          would
                          > > > >like
                          > > > > > > > > the mouse to go at about 1 meter per second, or maybe
                          faster)
                          > > > > > > > > > The maximum size for the robot is 16.8 cm. (~6.6 in)
                          > > squared
                          > > > > > > > > because the passage way is 18 cm. (~7 in) and the wall width
                          > > is 1.2
                          > > > >cm
                          > > > > > > > > (~.47 in). But I would the like the robot to be smaller than
                          > > that to
                          > > > >be
                          > > > > > > > > able to maneuver easily. The width of the robot is going to
                          > > have to
                          > > > >be
                          > > > > > >to
                          > > > > > > > > be is around 11 cm (4.4 in) if the base is a square, if it
                          is a
                          > > > >circle,
                          > > > > > > > > it could be slightly bigger. so the maximum length of the
                          motors
                          > > > >would
                          > > > > > > > > have to be 5.5 cm (2.2 in) because I don't want to use and
                          > > external
                          > > > >gear
                          > > > > > > > > train, I cant put the motors side by side, and if the
                          encoder
                          > > is on
                          > > > >the
                          > > > > > > > > shaft of the motor then I can't put and other gears because
                          > > of the
                          > > > > > > > > spacing in between the gear (each gear can rotate freely a
                          few
                          > > > >degrees).
                          > > > > > > > > The motor should have a gear train, even if it is outside in
                          > > a box.
                          > > > > > > > > > I have also though about the possibility of using
                          stepper
                          > > > >motors.
                          > > > > > > > > This way I wouldn't need to use the encoder, unless the
                          wheel
                          > > slips,
                          > > > >or
                          > > > > > > > > the stepper motor looses some steps. But stepper motors are
                          > > hard to
                          > > > > > >mount
                          > > > > > > > > because most of them have a pinion gear on there shaft, and
                          > > the ones
                          > > > > > >used
                          > > > > > > > > in old 5 1/4 drives weight too much. But it is something
                          that
                          > > I am
                          > > > > > >considering.
                          > > > > > > > > > I have tried to use a Lego design (I've built Lego
                          > > robots for
                          > > > >2
                          > > > > > > > > years with the Mindstorm line of kits, I've stopped now) but
                          I
                          > > > >couldn't
                          > > > > > > > > get it to be small enough the Lego gear motors are really
                          > > good, but
                          > > > >they
                          > > > > > > > > also go slow, and I had a difficult time mounting the
                          > > encoder, so I
                          > > > > > >tried
                          > > > > > > > > to use a gear, but the design wouldn't be small enough. I
                          then
                          > > > >though
                          > > > > > > > > about the Lego rotation sensor, but its signal is analog,
                          > > there are
                          > > > >4
                          > > > > > > > > different voltage level, at for different parts of the
                          cycle, but
                          > > > >then
                          > > > > > > > > this would require either a port on the ADC, or 4
                          comparators
                          > > (the
                          > > > >339
                          > > > > > > > > chip) and it would waste 4 I/O pins. AND it would be
                          > > inaccurate for
                          > > > > > >high
                          > > > > > > > > speeds.
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > > BTW. this is for my 7th grade science project. Idea of
                          the
                          > > > >project
                          > > > > > > > > is to identify which algorithm is more efficient, and faster
                          in
                          > > > >solving
                          > > > > > > > > the maze. I may make the use a different maze then the ones
                          > > used in
                          > > > > > > > > micromouse compition (maybe less cells, or the beginning and
                          end
                          > > > > > >location
                          > > > > > > > > is different). I chose this idea because it is more of a
                          > > programming
                          > > > > > > > > project, then a hardware project, and I am better at
                          software
                          > > than
                          > > > > > > > > hardware, I don't really have any mechanical skills, which
                          is
                          > > why I
                          > > > >want
                          > > > > > > > > to keep the actual motor hardware simple. My dad can help me
                          with
                          > > > >the
                          > > > > > > > > mechanical aspects of the project.
                          > > > > > > > > >
                          > > > > > > > > > These are some micromouse links if you want more
                          > > information
                          > > > > > > > > >
                          > > > > > > > > > http://micromouse.cannock.ac.uk/
                          > > > > > > > > >
                          > > > > > > > > > http://micromouse.cs.rhbnc.ac.uk/
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > >http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
                          > > > > > > > > >
                          > > > > > > > > > http://fused.org/projects/
                          > > > > > > > > >
                          > > > > > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
                          > > > > > > > > >
                          > > > > > > > > > http://www.ece.ucdavis.edu/umouse/
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > > And help is appreciated
                          > > > > > > > > >
                          > > > > > > > > > Rgds,
                          > > > > > > > > > Gustavo
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > > [Non-text portions of this message have been removed]
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                          > > > > > > > > >
                          > > > > > > > > > To unsubscribe from this group, send an email to:
                          > > > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                          > > > > > > > > >
                          > > > > > > > > >
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                          > > > > > >http://docs.yahoo.com/info/terms/
                          > > > > > > > > >
                          > > > > > > > > >
                          > > > > > > > >
                          > > > > > > > >[Non-text portions of this message have been removed]
                          > > > > > > > >
                          > > > > > > > >
                          > > > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                          > > > > > > > >
                          > > > > > > > >To unsubscribe from this group, send an email to:
                          > > > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                          > > > > > > > >
                          > > > > > > > >
                          > > > > > > > >Your use of Yahoo! Groups is subject to
                          > > > >http://docs.yahoo.com/info/terms/
                          > > > > > > >
                          > > > > > > >
                          > > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                          > > > > > > >
                          > > > > > > > To unsubscribe from this group, send an email to:
                          > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
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                          > > > > > > > Your use of Yahoo! Groups is subject to
                          > > > >http://docs.yahoo.com/info/terms/
                          > > > > > > >
                          > > > > > > >
                          > > > > > > >
                          > > > > > >
                          > > > > > >
                          > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                          > > > > > >
                          > > > > > >To unsubscribe from this group, send an email to:
                          > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
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                          > > http://docs.yahoo.com/info/terms/
                          > > > > >
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                          > > > > >
                          > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                          > > > > >
                          > > > > > To unsubscribe from this group, send an email to:
                          > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                          > > > > >
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                          > > > > > Your use of Yahoo! Groups is subject to
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                          > > > > >
                          > > > > >
                          > > > > >
                          > > > >
                          > > > >
                          > > > >Visit the SRS Website at http://www.seattlerobotics.org
                          > > > >
                          > > > >To unsubscribe from this group, send an email to:
                          > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                          > > > >
                          > > > >
                          > > > >Your use of Yahoo! Groups is subject to
                          http://docs.yahoo.com/info/terms/
                          > > >
                          > > >
                          > >
                          > >[Non-text portions of this message have been removed]
                          > >
                          > >
                          > >Visit the SRS Website at http://www.seattlerobotics.org
                          > >
                          > >To unsubscribe from this group, send an email to:
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                          > >
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                          >
                        • Tom Capon
                          Like I said, if you happen to be any good at electronics, you might try hacking an optical mouse, but otherwise there are lots of places that sell pre-cut
                          Message 12 of 15 , Aug 7, 2003
                            Like I said, if you happen to be any good at electronics, you might try
                            hacking an optical mouse, but otherwise there are lots of places that sell
                            pre-cut optical encoder disks.

                            At 05:08 AM 8/7/2003 -0400, Gustavo wrote:
                            >now all I need if a good encoder disk
                            >
                            >----- Original Message -----
                            >From: "Tom Capon" <robot@...>
                            >To: <seattlerobotics@yahoogroups.com>
                            >Sent: Wednesday, August 06, 2003 5:35 PM
                            >Subject: Re: [SeattleRobotics] Motors and Encoders
                            >
                            >
                            > > I just did some checking and if you can make do with larger wheels, they
                            > > have another gearmotor that will take you at about 20 cm per second with a
                            > > 6.5 cm diameter wheel. there are several other motors and wheels on that
                            > > page, just select "all" entries per page.
                            > >
                            > > At 02:45 PM 8/6/2003 -0400, Gustavo wrote:
                            > > >$800 dollars just for motors is way out of my budget :-(
                            > > >If I_use the solarbotics' gearmotor with their wheel, my robot will be
                            > > >able to go 1.3 cm a second. which is really slow
                            > > >
                            > > >I am still wondering how the other micromouse achieve this speed, see the
                            > > >links below for movies to see how fast they really go, well some of them.
                            > > >----- Original Message -----
                            > > >From: "Tom Capon" <robot@...>
                            > > >To: "Gustavo" <gustavo@...>; <seattlerobotics@yahoogroups.com>
                            > > >Sent: Wednesday, August 06, 2003 9:09 AM
                            > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                            > > >
                            > > >
                            > > > > If you make the wheels as big as possible and the motors actually have
                            > > > some
                            > > > > torque, it should speed in up quite a bit. Of course, if you aren't
                            > > > > satisfied with that, you could always get custom-built miniature
                            >gearhead
                            > > > > motors for $400 each. And if it has good traction and is very light,
                            >you
                            > > > > should be able to go pretty fast. Then there is the other aspect of
                            > > > > things: that unless you have really super-precision encoders or
                            > > > super-fast
                            > > > > optical rangefinding, it's going to be very difficult to control
                            > > > something
                            > > > > going that fast, even with a super-fast processor.
                            > > > >
                            > > > > At 03:40 AM 8/6/2003 -0400, Gustavo wrote:
                            > > > > >The pager motors are very fast, but they have near to no torque.
                            > > > > >I took a look at the Solorbotics website before, and the motors seem
                            >very
                            > > > > >good, but I don't think they are fast enough.
                            > > > > >I don't understand about what you mean that I don't know the
                            >direction the
                            > > > > >motor is going. If you apply power to it in a certain polarity it
                            >will
                            > > > go on
                            > > > > >way, and if you reverse the polarity it will rotate the other way
                            >(Not
                            > > > true
                            > > > > >for AC motors, or brushless fan motors).
                            > > > > >----- Original Message -----
                            > > > > >From: "Jim McBride" <mcbride7@...>
                            > > > > >To: <seattlerobotics@yahoogroups.com>
                            > > > > >Sent: Tuesday, August 05, 2003 10:27 PM
                            > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                            > > > > >
                            > > > > >
                            > > > > > > You may want to explore BEAM applications for small motors.
                            > > > > >Solarbotics.com
                            > > > > > > has a lot of useful miniature items.
                            > > > > > >
                            >http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
                            > > > > > >
                            > > > > > > Jim
                            > > > > > >
                            > > > > > > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
                            > > > > > > > How do the other micromice (can't think of a better word!)
                            >achieve
                            > > > > >this
                            > > > > > > >size and speed?
                            > > > > > > >I am currently learning how to use the ATMega16 / 32 because of
                            >its
                            > > > > >speed,
                            > > > > > > >but I am also learning how to program the Rabbitcore 2000 from
                            > > > > > > >http://www.rabbitsemiconductor.com/. It has a lot of RAM , and
                            >program
                            > > > > > > >memory, and has four serial ports. If I do use both of these
                            > > > processors
                            > > > > >then
                            > > > > > > >the Rabbit would be the master, and the ATMega would be the
                            >slave.
                            > > > I am
                            > > > > > > >planning in using the ATMega for controlling the motors, and
                            > > > reading the
                            > > > > > > >encoder and reading the other sensors (It has a built in ADC).
                            > > > > > > >
                            > > > > > > >
                            > > > > > > >
                            > > > > > > >----- Original Message -----
                            > > > > > > >From: "Tom Capon" <robot@...>
                            > > > > > > >To: <seattlerobotics@yahoogroups.com>
                            > > > > > > >Sent: Tuesday, August 05, 2003 11:24 AM
                            > > > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                            > > > > > > >
                            > > > > > > >
                            > > > > > > > >
                            > > > > > > > > Well, I think you're going to have a tough time making
                            > > > something that
                            > > > > > > >small
                            > > > > > > > > and that fast. You might want to look into pager motors, they
                            > > > can be
                            > > > > > > >found
                            > > > > > > > > most any surplus house. Assuming you're running this thing on
                            > > > a flat
                            > > > > > > > > table-top-like surface, you might even want to use a mouse as
                            > > > the body
                            > > > > >of
                            > > > > > > > > the robot. There are sites that explain how to hack a mouse
                            >to get
                            > > > > >the
                            > > > > > > > > encoder signals right out of the board without have to add
                            >your own
                            > > > > > > >drivers
                            > > > > > > > > and stuff. The only problem with the pager motors is that the
                            >are
                            > > > > > > > > fast. You would have to get about four of them maybe and put
                            >the
                            > > > > > > > > (computer) mouse on wheels. Just slip a bit of rubber tubing
                            > > > (really
                            > > > > > > >small
                            > > > > > > > > diameter) over the motor shaft and you've got a fairly good
                            > > > tire that
                            > > > > >will
                            > > > > > > > > gear it down a lot just by being small. If you get an optical
                            > > > mouse,
                            > > > > > > > > (under $20, probably) there would be much less friction and
                            >it
                            > > > would
                            > > > > >be
                            > > > > > > > > easier to control. there is a link to a site on how to hack
                            >an
                            > > > > >optical
                            > > > > > > > > mouse for encoder-like outputs on my site,
                            > > > > > > > > www.destructonet.org/tom/robotics . BTW, what microcontroller
                            > > > are you
                            > > > > > > >using?
                            > > > > > > > >
                            > > > > > > > >
                            > > > > > > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
                            > > > > > > > > >Sorry, Maybe I didn't make myself clear when I said :
                            > > > > > > > > >
                            > > > > > > > > >I don't want to use and external gear train, I cant put the
                            >motors
                            > > > > >side
                            > > > > > > >by
                            > > > > > > > > >side...
                            > > > > > > > > >
                            > > > > > > > > >I meant that the motors have to be like this:
                            > > > > > > > > > _______ ______
                            > > > > > > > > >shaft | | | |shaft
                            > > > > > > > > >--------|motor1 | |motor2 |--------
                            > > > > > > > > > |______| |______|
                            > > > > > > > > >
                            > > > > > > > > >
                            > > > > > > > > >and not like:
                            > > > > > > > > >
                            > > > > > > > > >
                            > > > > > > > > >___|___ ___|___
                            > > > > > > > > >| | | |
                            > > > > > > > > >|Motor1| |Motor2 |
                            > > > > > > > > >|______| |______ |
                            > > > > > > > > >
                            > > > > > > > > >
                            > > > > > > > > >or:
                            > > > > > > > > >
                            > > > > > > > > > |Gear
                            > > > > > > > > > | ________
                            > > > > > > > > >\/ | |
                            > > > > > > > > >*-------|Motor1 |
                            > > > > > > > > > |_______ |
                            > > > > > > > > >* ________ * bigger gear
                            > > > > > > > > >^ | |
                            > > > > > > > > >| |Motor2 |----------*
                            > > > > > > > > >| |_______ | ^
                            > > > > > > > > >| gear
                            > > > > > > > > >bigger gear
                            > > > > > > > > >
                            > > > > > > > > > the bigger gear is connected to the shaft.
                            > > > > > > > > >
                            > > > > > > > > >
                            > > > > > > > > >(Forgive me for the horrible ASCII art.)
                            > > > > > > > > >
                            > > > > > > > > >
                            > > > > > > > > >
                            > > > > > > > > >----- Original Message -----
                            > > > > > > > > >From: "Gustavo" <gustavo@...>
                            > > > > > > > > >To: <seattlerobotics@yahoogroups.com>
                            > > > > > > > > >Sent: Tuesday, August 05, 2003 5:10 AM
                            > > > > > > > > >Subject: [SeattleRobotics] Motors and Encoders
                            > > > > > > > > >
                            > > > > > > > > >
                            > > > > > > > > > > Hello,
                            > > > > > > > > > >
                            > > > > > > > > > > I'm looking for a suitable encoder, and motor (it
                            >doesn't
                            > > > > > > > > > necessarily have to be a single package) for a micromouse
                            > > > robot. I
                            > > > > >have
                            > > > > > > > > > tried to salvage optical encoders from computer mice, but I
                            >can't
                            > > > > >seem
                            > > > > > > >to
                            > > > > > > > > > get them coupled on the axles. I have thought of printing
                            >out an
                            > > > > >encoder
                            > > > > > > > > > on a transparency, but then it would be difficult to align,
                            > > > and it
                            > > > > >would
                            > > > > > > > > > probably bend. I have also though of just printing out an
                            >encoder
                            > > > > >with
                            > > > > > > > > > the sectors alternating black and white, but then I face two
                            > > > > >problems,
                            > > > > > > > > > the lack of resolution, and precision, and the lighting
                            > > > conditions
                            > > > > >that
                            > > > > > > > > > might affect the reading of the sensor. I don't need a lot
                            >of
                            > > > > > > >resolution,
                            > > > > > > > > > but at least around 30. as for the actual sensor, I don't
                            >need a
                            > > > > > > > > > quadrature because the direction that the motor is going is
                            >not
                            > > > > >needed
                            > > > > > > >(I
                            > > > > > > > > > control the motors, I know the direction I set them).
                            > > > > > > > > > >
                            > > > > > > > > > > As for the motors, I haven't tried servos, and I don't
                            > > > want to
                            > > > > >use
                            > > > > > > > > > them for rotations, if I do incorporate servos, it will be
                            >for
                            > > > > >rotating
                            > > > > > > >a
                            > > > > > > > > > "head" with various sensors. I need something with speed (I
                            >would
                            > > > > >like
                            > > > > > > > > > the mouse to go at about 1 meter per second, or maybe
                            >faster)
                            > > > > > > > > > > The maximum size for the robot is 16.8 cm. (~6.6 in)
                            > > > squared
                            > > > > > > > > > because the passage way is 18 cm. (~7 in) and the wall width
                            > > > is 1.2
                            > > > > >cm
                            > > > > > > > > > (~.47 in). But I would the like the robot to be smaller than
                            > > > that to
                            > > > > >be
                            > > > > > > > > > able to maneuver easily. The width of the robot is going to
                            > > > have to
                            > > > > >be
                            > > > > > > >to
                            > > > > > > > > > be is around 11 cm (4.4 in) if the base is a square, if it
                            >is a
                            > > > > >circle,
                            > > > > > > > > > it could be slightly bigger. so the maximum length of the
                            >motors
                            > > > > >would
                            > > > > > > > > > have to be 5.5 cm (2.2 in) because I don't want to use and
                            > > > external
                            > > > > >gear
                            > > > > > > > > > train, I cant put the motors side by side, and if the
                            >encoder
                            > > > is on
                            > > > > >the
                            > > > > > > > > > shaft of the motor then I can't put and other gears because
                            > > > of the
                            > > > > > > > > > spacing in between the gear (each gear can rotate freely a
                            >few
                            > > > > >degrees).
                            > > > > > > > > > The motor should have a gear train, even if it is outside in
                            > > > a box.
                            > > > > > > > > > > I have also though about the possibility of using
                            >stepper
                            > > > > >motors.
                            > > > > > > > > > This way I wouldn't need to use the encoder, unless the
                            >wheel
                            > > > slips,
                            > > > > >or
                            > > > > > > > > > the stepper motor looses some steps. But stepper motors are
                            > > > hard to
                            > > > > > > >mount
                            > > > > > > > > > because most of them have a pinion gear on there shaft, and
                            > > > the ones
                            > > > > > > >used
                            > > > > > > > > > in old 5 1/4 drives weight too much. But it is something
                            >that
                            > > > I am
                            > > > > > > >considering.
                            > > > > > > > > > > I have tried to use a Lego design (I've built Lego
                            > > > robots for
                            > > > > >2
                            > > > > > > > > > years with the Mindstorm line of kits, I've stopped now) but
                            >I
                            > > > > >couldn't
                            > > > > > > > > > get it to be small enough the Lego gear motors are really
                            > > > good, but
                            > > > > >they
                            > > > > > > > > > also go slow, and I had a difficult time mounting the
                            > > > encoder, so I
                            > > > > > > >tried
                            > > > > > > > > > to use a gear, but the design wouldn't be small enough. I
                            >then
                            > > > > >though
                            > > > > > > > > > about the Lego rotation sensor, but its signal is analog,
                            > > > there are
                            > > > > >4
                            > > > > > > > > > different voltage level, at for different parts of the
                            >cycle, but
                            > > > > >then
                            > > > > > > > > > this would require either a port on the ADC, or 4
                            >comparators
                            > > > (the
                            > > > > >339
                            > > > > > > > > > chip) and it would waste 4 I/O pins. AND it would be
                            > > > inaccurate for
                            > > > > > > >high
                            > > > > > > > > > speeds.
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > > BTW. this is for my 7th grade science project. Idea of
                            >the
                            > > > > >project
                            > > > > > > > > > is to identify which algorithm is more efficient, and faster
                            >in
                            > > > > >solving
                            > > > > > > > > > the maze. I may make the use a different maze then the ones
                            > > > used in
                            > > > > > > > > > micromouse compition (maybe less cells, or the beginning and
                            >end
                            > > > > > > >location
                            > > > > > > > > > is different). I chose this idea because it is more of a
                            > > > programming
                            > > > > > > > > > project, then a hardware project, and I am better at
                            >software
                            > > > than
                            > > > > > > > > > hardware, I don't really have any mechanical skills, which
                            >is
                            > > > why I
                            > > > > >want
                            > > > > > > > > > to keep the actual motor hardware simple. My dad can help me
                            >with
                            > > > > >the
                            > > > > > > > > > mechanical aspects of the project.
                            > > > > > > > > > >
                            > > > > > > > > > > These are some micromouse links if you want more
                            > > > information
                            > > > > > > > > > >
                            > > > > > > > > > > http://micromouse.cannock.ac.uk/
                            > > > > > > > > > >
                            > > > > > > > > > > http://micromouse.cs.rhbnc.ac.uk/
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > >http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
                            > > > > > > > > > >
                            > > > > > > > > > > http://fused.org/projects/
                            > > > > > > > > > >
                            > > > > > > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
                            > > > > > > > > > >
                            > > > > > > > > > > http://www.ece.ucdavis.edu/umouse/
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > > And help is appreciated
                            > > > > > > > > > >
                            > > > > > > > > > > Rgds,
                            > > > > > > > > > > Gustavo
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > >
                            > > > > > > > > > > [Non-text portions of this message have been removed]
                            > > > > > > > > > >
                            > > > > > > > > > >
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                          • Gustavo
                            By optical, are you saying the mouse that has a camera, and DSP, or the one with two encoder disks, perpendicular to one another? If already manages to get two
                            Message 13 of 15 , Aug 7, 2003
                              By optical, are you saying the mouse that has a camera, and DSP, or the one
                              with two encoder disks, perpendicular to one another?

                              If already manages to get two encoder disks out of a mouse, that's not the
                              problem, and I don't need to use any of the mouse's electronics because I
                              have a bunch of optocouplers I bought from www.goldmine-elec.com . My only
                              problem is mounting the encoder disk on the axle of the wheel. The gear
                              motors that I have been looking at (Gearmotor 8, Gearmotor 9) don't seem to
                              have an axle long enough, I might need to modify it if I buy it.
                              ----- Original Message -----
                              From: "Tom Capon" <robot@...>
                              To: <seattlerobotics@yahoogroups.com>
                              Sent: Thursday, August 07, 2003 9:58 AM
                              Subject: Re: [SeattleRobotics] Motors and Encoders


                              > Like I said, if you happen to be any good at electronics, you might try
                              > hacking an optical mouse, but otherwise there are lots of places that sell
                              > pre-cut optical encoder disks.
                              >
                              > At 05:08 AM 8/7/2003 -0400, Gustavo wrote:
                              > >now all I need if a good encoder disk
                              > >
                              > >----- Original Message -----
                              > >From: "Tom Capon" <robot@...>
                              > >To: <seattlerobotics@yahoogroups.com>
                              > >Sent: Wednesday, August 06, 2003 5:35 PM
                              > >Subject: Re: [SeattleRobotics] Motors and Encoders
                              > >
                              > >
                              > > > I just did some checking and if you can make do with larger wheels,
                              they
                              > > > have another gearmotor that will take you at about 20 cm per second
                              with a
                              > > > 6.5 cm diameter wheel. there are several other motors and wheels on
                              that
                              > > > page, just select "all" entries per page.
                              > > >
                              > > > At 02:45 PM 8/6/2003 -0400, Gustavo wrote:
                              > > > >$800 dollars just for motors is way out of my budget :-(
                              > > > >If I_use the solarbotics' gearmotor with their wheel, my robot will
                              be
                              > > > >able to go 1.3 cm a second. which is really slow
                              > > > >
                              > > > >I am still wondering how the other micromouse achieve this speed, see
                              the
                              > > > >links below for movies to see how fast they really go, well some of
                              them.
                              > > > >----- Original Message -----
                              > > > >From: "Tom Capon" <robot@...>
                              > > > >To: "Gustavo" <gustavo@...>;
                              <seattlerobotics@yahoogroups.com>
                              > > > >Sent: Wednesday, August 06, 2003 9:09 AM
                              > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                              > > > >
                              > > > >
                              > > > > > If you make the wheels as big as possible and the motors actually
                              have
                              > > > > some
                              > > > > > torque, it should speed in up quite a bit. Of course, if you
                              aren't
                              > > > > > satisfied with that, you could always get custom-built miniature
                              > >gearhead
                              > > > > > motors for $400 each. And if it has good traction and is very
                              light,
                              > >you
                              > > > > > should be able to go pretty fast. Then there is the other aspect
                              of
                              > > > > > things: that unless you have really super-precision encoders or
                              > > > > super-fast
                              > > > > > optical rangefinding, it's going to be very difficult to control
                              > > > > something
                              > > > > > going that fast, even with a super-fast processor.
                              > > > > >
                              > > > > > At 03:40 AM 8/6/2003 -0400, Gustavo wrote:
                              > > > > > >The pager motors are very fast, but they have near to no torque.
                              > > > > > >I took a look at the Solorbotics website before, and the motors
                              seem
                              > >very
                              > > > > > >good, but I don't think they are fast enough.
                              > > > > > >I don't understand about what you mean that I don't know the
                              > >direction the
                              > > > > > >motor is going. If you apply power to it in a certain polarity it
                              > >will
                              > > > > go on
                              > > > > > >way, and if you reverse the polarity it will rotate the other way
                              > >(Not
                              > > > > true
                              > > > > > >for AC motors, or brushless fan motors).
                              > > > > > >----- Original Message -----
                              > > > > > >From: "Jim McBride" <mcbride7@...>
                              > > > > > >To: <seattlerobotics@yahoogroups.com>
                              > > > > > >Sent: Tuesday, August 05, 2003 10:27 PM
                              > > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                              > > > > > >
                              > > > > > >
                              > > > > > > > You may want to explore BEAM applications for small motors.
                              > > > > > >Solarbotics.com
                              > > > > > > > has a lot of useful miniature items.
                              > > > > > > >
                              > >http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
                              > > > > > > >
                              > > > > > > > Jim
                              > > > > > > >
                              > > > > > > > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
                              > > > > > > > > How do the other micromice (can't think of a better word!)
                              > >achieve
                              > > > > > >this
                              > > > > > > > >size and speed?
                              > > > > > > > >I am currently learning how to use the ATMega16 / 32 because
                              of
                              > >its
                              > > > > > >speed,
                              > > > > > > > >but I am also learning how to program the Rabbitcore 2000
                              from
                              > > > > > > > >http://www.rabbitsemiconductor.com/. It has a lot of RAM ,
                              and
                              > >program
                              > > > > > > > >memory, and has four serial ports. If I do use both of these
                              > > > > processors
                              > > > > > >then
                              > > > > > > > >the Rabbit would be the master, and the ATMega would be the
                              > >slave.
                              > > > > I am
                              > > > > > > > >planning in using the ATMega for controlling the motors, and
                              > > > > reading the
                              > > > > > > > >encoder and reading the other sensors (It has a built in
                              ADC).
                              > > > > > > > >
                              > > > > > > > >
                              > > > > > > > >
                              > > > > > > > >----- Original Message -----
                              > > > > > > > >From: "Tom Capon" <robot@...>
                              > > > > > > > >To: <seattlerobotics@yahoogroups.com>
                              > > > > > > > >Sent: Tuesday, August 05, 2003 11:24 AM
                              > > > > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                              > > > > > > > >
                              > > > > > > > >
                              > > > > > > > > >
                              > > > > > > > > > Well, I think you're going to have a tough time making
                              > > > > something that
                              > > > > > > > >small
                              > > > > > > > > > and that fast. You might want to look into pager motors,
                              they
                              > > > > can be
                              > > > > > > > >found
                              > > > > > > > > > most any surplus house. Assuming you're running this
                              thing on
                              > > > > a flat
                              > > > > > > > > > table-top-like surface, you might even want to use a mouse
                              as
                              > > > > the body
                              > > > > > >of
                              > > > > > > > > > the robot. There are sites that explain how to hack a
                              mouse
                              > >to get
                              > > > > > >the
                              > > > > > > > > > encoder signals right out of the board without have to add
                              > >your own
                              > > > > > > > >drivers
                              > > > > > > > > > and stuff. The only problem with the pager motors is that
                              the
                              > >are
                              > > > > > > > > > fast. You would have to get about four of them maybe and
                              put
                              > >the
                              > > > > > > > > > (computer) mouse on wheels. Just slip a bit of rubber
                              tubing
                              > > > > (really
                              > > > > > > > >small
                              > > > > > > > > > diameter) over the motor shaft and you've got a fairly
                              good
                              > > > > tire that
                              > > > > > >will
                              > > > > > > > > > gear it down a lot just by being small. If you get an
                              optical
                              > > > > mouse,
                              > > > > > > > > > (under $20, probably) there would be much less friction
                              and
                              > >it
                              > > > > would
                              > > > > > >be
                              > > > > > > > > > easier to control. there is a link to a site on how to
                              hack
                              > >an
                              > > > > > >optical
                              > > > > > > > > > mouse for encoder-like outputs on my site,
                              > > > > > > > > > www.destructonet.org/tom/robotics . BTW, what
                              microcontroller
                              > > > > are you
                              > > > > > > > >using?
                              > > > > > > > > >
                              > > > > > > > > >
                              > > > > > > > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
                              > > > > > > > > > >Sorry, Maybe I didn't make myself clear when I said :
                              > > > > > > > > > >
                              > > > > > > > > > >I don't want to use and external gear train, I cant put
                              the
                              > >motors
                              > > > > > >side
                              > > > > > > > >by
                              > > > > > > > > > >side...
                              > > > > > > > > > >
                              > > > > > > > > > >I meant that the motors have to be like this:
                              > > > > > > > > > > _______ ______
                              > > > > > > > > > >shaft | | | |shaft
                              > > > > > > > > > >--------|motor1 | |motor2 |--------
                              > > > > > > > > > > |______| |______|
                              > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > >and not like:
                              > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > >___|___ ___|___
                              > > > > > > > > > >| | | |
                              > > > > > > > > > >|Motor1| |Motor2 |
                              > > > > > > > > > >|______| |______ |
                              > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > >or:
                              > > > > > > > > > >
                              > > > > > > > > > > |Gear
                              > > > > > > > > > > | ________
                              > > > > > > > > > >\/ | |
                              > > > > > > > > > >*-------|Motor1 |
                              > > > > > > > > > > |_______ |
                              > > > > > > > > > >* ________ * bigger gear
                              > > > > > > > > > >^ | |
                              > > > > > > > > > >| |Motor2 |----------*
                              > > > > > > > > > >| |_______ | ^
                              > > > > > > > > > >| gear
                              > > > > > > > > > >bigger gear
                              > > > > > > > > > >
                              > > > > > > > > > > the bigger gear is connected to the shaft.
                              > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > >(Forgive me for the horrible ASCII art.)
                              > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > >----- Original Message -----
                              > > > > > > > > > >From: "Gustavo" <gustavo@...>
                              > > > > > > > > > >To: <seattlerobotics@yahoogroups.com>
                              > > > > > > > > > >Sent: Tuesday, August 05, 2003 5:10 AM
                              > > > > > > > > > >Subject: [SeattleRobotics] Motors and Encoders
                              > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > > > Hello,
                              > > > > > > > > > > >
                              > > > > > > > > > > > I'm looking for a suitable encoder, and motor (it
                              > >doesn't
                              > > > > > > > > > > necessarily have to be a single package) for a
                              micromouse
                              > > > > robot. I
                              > > > > > >have
                              > > > > > > > > > > tried to salvage optical encoders from computer mice,
                              but I
                              > >can't
                              > > > > > >seem
                              > > > > > > > >to
                              > > > > > > > > > > get them coupled on the axles. I have thought of
                              printing
                              > >out an
                              > > > > > >encoder
                              > > > > > > > > > > on a transparency, but then it would be difficult to
                              align,
                              > > > > and it
                              > > > > > >would
                              > > > > > > > > > > probably bend. I have also though of just printing out
                              an
                              > >encoder
                              > > > > > >with
                              > > > > > > > > > > the sectors alternating black and white, but then I face
                              two
                              > > > > > >problems,
                              > > > > > > > > > > the lack of resolution, and precision, and the lighting
                              > > > > conditions
                              > > > > > >that
                              > > > > > > > > > > might affect the reading of the sensor. I don't need a
                              lot
                              > >of
                              > > > > > > > >resolution,
                              > > > > > > > > > > but at least around 30. as for the actual sensor, I
                              don't
                              > >need a
                              > > > > > > > > > > quadrature because the direction that the motor is going
                              is
                              > >not
                              > > > > > >needed
                              > > > > > > > >(I
                              > > > > > > > > > > control the motors, I know the direction I set them).
                              > > > > > > > > > > >
                              > > > > > > > > > > > As for the motors, I haven't tried servos, and I
                              don't
                              > > > > want to
                              > > > > > >use
                              > > > > > > > > > > them for rotations, if I do incorporate servos, it will
                              be
                              > >for
                              > > > > > >rotating
                              > > > > > > > >a
                              > > > > > > > > > > "head" with various sensors. I need something with speed
                              (I
                              > >would
                              > > > > > >like
                              > > > > > > > > > > the mouse to go at about 1 meter per second, or maybe
                              > >faster)
                              > > > > > > > > > > > The maximum size for the robot is 16.8 cm. (~6.6
                              in)
                              > > > > squared
                              > > > > > > > > > > because the passage way is 18 cm. (~7 in) and the wall
                              width
                              > > > > is 1.2
                              > > > > > >cm
                              > > > > > > > > > > (~.47 in). But I would the like the robot to be smaller
                              than
                              > > > > that to
                              > > > > > >be
                              > > > > > > > > > > able to maneuver easily. The width of the robot is going
                              to
                              > > > > have to
                              > > > > > >be
                              > > > > > > > >to
                              > > > > > > > > > > be is around 11 cm (4.4 in) if the base is a square, if
                              it
                              > >is a
                              > > > > > >circle,
                              > > > > > > > > > > it could be slightly bigger. so the maximum length of
                              the
                              > >motors
                              > > > > > >would
                              > > > > > > > > > > have to be 5.5 cm (2.2 in) because I don't want to use
                              and
                              > > > > external
                              > > > > > >gear
                              > > > > > > > > > > train, I cant put the motors side by side, and if the
                              > >encoder
                              > > > > is on
                              > > > > > >the
                              > > > > > > > > > > shaft of the motor then I can't put and other gears
                              because
                              > > > > of the
                              > > > > > > > > > > spacing in between the gear (each gear can rotate freely
                              a
                              > >few
                              > > > > > >degrees).
                              > > > > > > > > > > The motor should have a gear train, even if it is
                              outside in
                              > > > > a box.
                              > > > > > > > > > > > I have also though about the possibility of using
                              > >stepper
                              > > > > > >motors.
                              > > > > > > > > > > This way I wouldn't need to use the encoder, unless the
                              > >wheel
                              > > > > slips,
                              > > > > > >or
                              > > > > > > > > > > the stepper motor looses some steps. But stepper motors
                              are
                              > > > > hard to
                              > > > > > > > >mount
                              > > > > > > > > > > because most of them have a pinion gear on there shaft,
                              and
                              > > > > the ones
                              > > > > > > > >used
                              > > > > > > > > > > in old 5 1/4 drives weight too much. But it is something
                              > >that
                              > > > > I am
                              > > > > > > > >considering.
                              > > > > > > > > > > > I have tried to use a Lego design (I've built Lego
                              > > > > robots for
                              > > > > > >2
                              > > > > > > > > > > years with the Mindstorm line of kits, I've stopped now)
                              but
                              > >I
                              > > > > > >couldn't
                              > > > > > > > > > > get it to be small enough the Lego gear motors are
                              really
                              > > > > good, but
                              > > > > > >they
                              > > > > > > > > > > also go slow, and I had a difficult time mounting the
                              > > > > encoder, so I
                              > > > > > > > >tried
                              > > > > > > > > > > to use a gear, but the design wouldn't be small enough.
                              I
                              > >then
                              > > > > > >though
                              > > > > > > > > > > about the Lego rotation sensor, but its signal is
                              analog,
                              > > > > there are
                              > > > > > >4
                              > > > > > > > > > > different voltage level, at for different parts of the
                              > >cycle, but
                              > > > > > >then
                              > > > > > > > > > > this would require either a port on the ADC, or 4
                              > >comparators
                              > > > > (the
                              > > > > > >339
                              > > > > > > > > > > chip) and it would waste 4 I/O pins. AND it would be
                              > > > > inaccurate for
                              > > > > > > > >high
                              > > > > > > > > > > speeds.
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > > BTW. this is for my 7th grade science project.
                              Idea of
                              > >the
                              > > > > > >project
                              > > > > > > > > > > is to identify which algorithm is more efficient, and
                              faster
                              > >in
                              > > > > > >solving
                              > > > > > > > > > > the maze. I may make the use a different maze then the
                              ones
                              > > > > used in
                              > > > > > > > > > > micromouse compition (maybe less cells, or the beginning
                              and
                              > >end
                              > > > > > > > >location
                              > > > > > > > > > > is different). I chose this idea because it is more of a
                              > > > > programming
                              > > > > > > > > > > project, then a hardware project, and I am better at
                              > >software
                              > > > > than
                              > > > > > > > > > > hardware, I don't really have any mechanical skills,
                              which
                              > >is
                              > > > > why I
                              > > > > > >want
                              > > > > > > > > > > to keep the actual motor hardware simple. My dad can
                              help me
                              > >with
                              > > > > > >the
                              > > > > > > > > > > mechanical aspects of the project.
                              > > > > > > > > > > >
                              > > > > > > > > > > > These are some micromouse links if you want more
                              > > > > information
                              > > > > > > > > > > >
                              > > > > > > > > > > > http://micromouse.cannock.ac.uk/
                              > > > > > > > > > > >
                              > > > > > > > > > > > http://micromouse.cs.rhbnc.ac.uk/
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > >
                              >http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
                              > > > > > > > > > > >
                              > > > > > > > > > > > http://fused.org/projects/
                              > > > > > > > > > > >
                              > > > > > > > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
                              > > > > > > > > > > >
                              > > > > > > > > > > > http://www.ece.ucdavis.edu/umouse/
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > > And help is appreciated
                              > > > > > > > > > > >
                              > > > > > > > > > > > Rgds,
                              > > > > > > > > > > > Gustavo
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > > [Non-text portions of this message have been removed]
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > > Visit the SRS Website at
                              http://www.seattlerobotics.org
                              > > > > > > > > > > >
                              > > > > > > > > > > > To unsubscribe from this group, send an email to:
                              > > > > > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > > > Your use of Yahoo! Groups is subject to
                              > > > > > > > >http://docs.yahoo.com/info/terms/
                              > > > > > > > > > > >
                              > > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > >[Non-text portions of this message have been removed]
                              > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                              > > > > > > > > > >
                              > > > > > > > > > >To unsubscribe from this group, send an email to:
                              > > > > > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                              > > > > > > > > > >
                              > > > > > > > > > >
                              > > > > > > > > > >Your use of Yahoo! Groups is subject to
                              > > > > > >http://docs.yahoo.com/info/terms/
                              > > > > > > > > >
                              > > > > > > > > >
                              > > > > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                              > > > > > > > > >
                              > > > > > > > > > To unsubscribe from this group, send an email to:
                              > > > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                              > > > > > > > > >
                              > > > > > > > > >
                              > > > > > > > > > Your use of Yahoo! Groups is subject to
                              > > > > > >http://docs.yahoo.com/info/terms/
                              > > > > > > > > >
                              > > > > > > > > >
                              > > > > > > > > >
                              > > > > > > > >
                              > > > > > > > >
                              > > > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                              > > > > > > > >
                              > > > > > > > >To unsubscribe from this group, send an email to:
                              > > > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                              > > > > > > > >
                              > > > > > > > >
                              > > > > > > > >Your use of Yahoo! Groups is subject to
                              > > > > http://docs.yahoo.com/info/terms/
                              > > > > > > >
                              > > > > > > >
                              > > > > > > >
                              > > > > > > > Visit the SRS Website at http://www.seattlerobotics.org
                              > > > > > > >
                              > > > > > > > To unsubscribe from this group, send an email to:
                              > > > > > > > SeattleRobotics-unsubscribe@yahoogroups.com
                              > > > > > > >
                              > > > > > > >
                              > > > > > > > Your use of Yahoo! Groups is subject to
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                              > > > > > > >
                              > > > > > > >
                              > > > > > > >
                              > > > > > >
                              > > > > > >
                              > > > > > >Visit the SRS Website at http://www.seattlerobotics.org
                              > > > > > >
                              > > > > > >To unsubscribe from this group, send an email to:
                              > > > > > >SeattleRobotics-unsubscribe@yahoogroups.com
                              > > > > > >
                              > > > > > >
                              > > > > > >Your use of Yahoo! Groups is subject to
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                              > > > > >
                              > > > > >
                              > > > >
                              > > > >[Non-text portions of this message have been removed]
                              > > > >
                              > > > >
                              > > > >Visit the SRS Website at http://www.seattlerobotics.org
                              > > > >
                              > > > >To unsubscribe from this group, send an email to:
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                              > > > >
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                              > > > Visit the SRS Website at http://www.seattlerobotics.org
                              > > >
                              > > > To unsubscribe from this group, send an email to:
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                              > > >
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                              > >
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                              >
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                              > Visit the SRS Website at http://www.seattlerobotics.org
                              >
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                              > SeattleRobotics-unsubscribe@yahoogroups.com
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                              >
                            • Gustavo
                              Oops, quite a lot of errors on that last email, sorry I was tired. I bought a bunch of Opto-Interrupters from Electronic Goldmine ... From: Gustavo
                              Message 14 of 15 , Aug 8, 2003
                                Oops, quite a lot of errors on that last email, sorry I was tired.
                                I bought a bunch of Opto-Interrupters from Electronic Goldmine
                                ----- Original Message -----
                                From: "Gustavo" <gustavo@...>
                                To: <seattlerobotics@yahoogroups.com>
                                Sent: Thursday, August 07, 2003 4:59 PM
                                Subject: Re: [SeattleRobotics] Motors and Encoders


                                > By optical, are you saying the mouse that has a camera, and DSP, or the
                                one
                                > with two encoder disks, perpendicular to one another?
                                >
                                > If already manages to get two encoder disks out of a mouse, that's not the
                                > problem, and I don't need to use any of the mouse's electronics because I
                                > have a bunch of optocouplers I bought from www.goldmine-elec.com . My
                                only
                                > problem is mounting the encoder disk on the axle of the wheel. The gear
                                > motors that I have been looking at (Gearmotor 8, Gearmotor 9) don't seem
                                to
                                > have an axle long enough, I might need to modify it if I buy it.
                                > ----- Original Message -----
                                > From: "Tom Capon" <robot@...>
                                > To: <seattlerobotics@yahoogroups.com>
                                > Sent: Thursday, August 07, 2003 9:58 AM
                                > Subject: Re: [SeattleRobotics] Motors and Encoders
                                >
                                >
                                > > Like I said, if you happen to be any good at electronics, you might try
                                > > hacking an optical mouse, but otherwise there are lots of places that
                                sell
                                > > pre-cut optical encoder disks.
                                > >
                                > > At 05:08 AM 8/7/2003 -0400, Gustavo wrote:
                                > > >now all I need if a good encoder disk
                                > > >
                                > > >----- Original Message -----
                                > > >From: "Tom Capon" <robot@...>
                                > > >To: <seattlerobotics@yahoogroups.com>
                                > > >Sent: Wednesday, August 06, 2003 5:35 PM
                                > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                                > > >
                                > > >
                                > > > > I just did some checking and if you can make do with larger wheels,
                                > they
                                > > > > have another gearmotor that will take you at about 20 cm per second
                                > with a
                                > > > > 6.5 cm diameter wheel. there are several other motors and wheels on
                                > that
                                > > > > page, just select "all" entries per page.
                                > > > >
                                > > > > At 02:45 PM 8/6/2003 -0400, Gustavo wrote:
                                > > > > >$800 dollars just for motors is way out of my budget :-(
                                > > > > >If I_use the solarbotics' gearmotor with their wheel, my robot will
                                > be
                                > > > > >able to go 1.3 cm a second. which is really slow
                                > > > > >
                                > > > > >I am still wondering how the other micromouse achieve this speed,
                                see
                                > the
                                > > > > >links below for movies to see how fast they really go, well some of
                                > them.
                                > > > > >----- Original Message -----
                                > > > > >From: "Tom Capon" <robot@...>
                                > > > > >To: "Gustavo" <gustavo@...>;
                                > <seattlerobotics@yahoogroups.com>
                                > > > > >Sent: Wednesday, August 06, 2003 9:09 AM
                                > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                                > > > > >
                                > > > > >
                                > > > > > > If you make the wheels as big as possible and the motors
                                actually
                                > have
                                > > > > > some
                                > > > > > > torque, it should speed in up quite a bit. Of course, if you
                                > aren't
                                > > > > > > satisfied with that, you could always get custom-built miniature
                                > > >gearhead
                                > > > > > > motors for $400 each. And if it has good traction and is very
                                > light,
                                > > >you
                                > > > > > > should be able to go pretty fast. Then there is the other
                                aspect
                                > of
                                > > > > > > things: that unless you have really super-precision encoders or
                                > > > > > super-fast
                                > > > > > > optical rangefinding, it's going to be very difficult to
                                control
                                > > > > > something
                                > > > > > > going that fast, even with a super-fast processor.
                                > > > > > >
                                > > > > > > At 03:40 AM 8/6/2003 -0400, Gustavo wrote:
                                > > > > > > >The pager motors are very fast, but they have near to no
                                torque.
                                > > > > > > >I took a look at the Solorbotics website before, and the motors
                                > seem
                                > > >very
                                > > > > > > >good, but I don't think they are fast enough.
                                > > > > > > >I don't understand about what you mean that I don't know the
                                > > >direction the
                                > > > > > > >motor is going. If you apply power to it in a certain polarity
                                it
                                > > >will
                                > > > > > go on
                                > > > > > > >way, and if you reverse the polarity it will rotate the other
                                way
                                > > >(Not
                                > > > > > true
                                > > > > > > >for AC motors, or brushless fan motors).
                                > > > > > > >----- Original Message -----
                                > > > > > > >From: "Jim McBride" <mcbride7@...>
                                > > > > > > >To: <seattlerobotics@yahoogroups.com>
                                > > > > > > >Sent: Tuesday, August 05, 2003 10:27 PM
                                > > > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                                > > > > > > >
                                > > > > > > >
                                > > > > > > > > You may want to explore BEAM applications for small motors.
                                > > > > > > >Solarbotics.com
                                > > > > > > > > has a lot of useful miniature items.
                                > > > > > > > >
                                > > >http://www.solarbotics.com/order/default.asp?PG=1&ACTION=CAT&CATID=8
                                > > > > > > > >
                                > > > > > > > > Jim
                                > > > > > > > >
                                > > > > > > > > At 04:48 PM 8/5/2003 -0400, Gustavo wrote:
                                > > > > > > > > > How do the other micromice (can't think of a better
                                word!)
                                > > >achieve
                                > > > > > > >this
                                > > > > > > > > >size and speed?
                                > > > > > > > > >I am currently learning how to use the ATMega16 / 32
                                because
                                > of
                                > > >its
                                > > > > > > >speed,
                                > > > > > > > > >but I am also learning how to program the Rabbitcore 2000
                                > from
                                > > > > > > > > >http://www.rabbitsemiconductor.com/. It has a lot of RAM ,
                                > and
                                > > >program
                                > > > > > > > > >memory, and has four serial ports. If I do use both of
                                these
                                > > > > > processors
                                > > > > > > >then
                                > > > > > > > > >the Rabbit would be the master, and the ATMega would be the
                                > > >slave.
                                > > > > > I am
                                > > > > > > > > >planning in using the ATMega for controlling the motors,
                                and
                                > > > > > reading the
                                > > > > > > > > >encoder and reading the other sensors (It has a built in
                                > ADC).
                                > > > > > > > > >
                                > > > > > > > > >
                                > > > > > > > > >
                                > > > > > > > > >----- Original Message -----
                                > > > > > > > > >From: "Tom Capon" <robot@...>
                                > > > > > > > > >To: <seattlerobotics@yahoogroups.com>
                                > > > > > > > > >Sent: Tuesday, August 05, 2003 11:24 AM
                                > > > > > > > > >Subject: Re: [SeattleRobotics] Motors and Encoders
                                > > > > > > > > >
                                > > > > > > > > >
                                > > > > > > > > > >
                                > > > > > > > > > > Well, I think you're going to have a tough time making
                                > > > > > something that
                                > > > > > > > > >small
                                > > > > > > > > > > and that fast. You might want to look into pager
                                motors,
                                > they
                                > > > > > can be
                                > > > > > > > > >found
                                > > > > > > > > > > most any surplus house. Assuming you're running this
                                > thing on
                                > > > > > a flat
                                > > > > > > > > > > table-top-like surface, you might even want to use a
                                mouse
                                > as
                                > > > > > the body
                                > > > > > > >of
                                > > > > > > > > > > the robot. There are sites that explain how to hack a
                                > mouse
                                > > >to get
                                > > > > > > >the
                                > > > > > > > > > > encoder signals right out of the board without have to
                                add
                                > > >your own
                                > > > > > > > > >drivers
                                > > > > > > > > > > and stuff. The only problem with the pager motors is
                                that
                                > the
                                > > >are
                                > > > > > > > > > > fast. You would have to get about four of them maybe
                                and
                                > put
                                > > >the
                                > > > > > > > > > > (computer) mouse on wheels. Just slip a bit of rubber
                                > tubing
                                > > > > > (really
                                > > > > > > > > >small
                                > > > > > > > > > > diameter) over the motor shaft and you've got a fairly
                                > good
                                > > > > > tire that
                                > > > > > > >will
                                > > > > > > > > > > gear it down a lot just by being small. If you get an
                                > optical
                                > > > > > mouse,
                                > > > > > > > > > > (under $20, probably) there would be much less friction
                                > and
                                > > >it
                                > > > > > would
                                > > > > > > >be
                                > > > > > > > > > > easier to control. there is a link to a site on how to
                                > hack
                                > > >an
                                > > > > > > >optical
                                > > > > > > > > > > mouse for encoder-like outputs on my site,
                                > > > > > > > > > > www.destructonet.org/tom/robotics . BTW, what
                                > microcontroller
                                > > > > > are you
                                > > > > > > > > >using?
                                > > > > > > > > > >
                                > > > > > > > > > >
                                > > > > > > > > > > At 05:39 AM 8/5/2003 -0400, Gustavo wrote:
                                > > > > > > > > > > >Sorry, Maybe I didn't make myself clear when I said :
                                > > > > > > > > > > >
                                > > > > > > > > > > >I don't want to use and external gear train, I cant put
                                > the
                                > > >motors
                                > > > > > > >side
                                > > > > > > > > >by
                                > > > > > > > > > > >side...
                                > > > > > > > > > > >
                                > > > > > > > > > > >I meant that the motors have to be like this:
                                > > > > > > > > > > > _______ ______
                                > > > > > > > > > > >shaft | | | |shaft
                                > > > > > > > > > > >--------|motor1 | |motor2 |--------
                                > > > > > > > > > > > |______| |______|
                                > > > > > > > > > > >
                                > > > > > > > > > > >
                                > > > > > > > > > > >and not like:
                                > > > > > > > > > > >
                                > > > > > > > > > > >
                                > > > > > > > > > > >___|___ ___|___
                                > > > > > > > > > > >| | | |
                                > > > > > > > > > > >|Motor1| |Motor2 |
                                > > > > > > > > > > >|______| |______ |
                                > > > > > > > > > > >
                                > > > > > > > > > > >
                                > > > > > > > > > > >or:
                                > > > > > > > > > > >
                                > > > > > > > > > > > |Gear
                                > > > > > > > > > > > | ________
                                > > > > > > > > > > >\/ | |
                                > > > > > > > > > > >*-------|Motor1 |
                                > > > > > > > > > > > |_______ |
                                > > > > > > > > > > >* ________ * bigger gear
                                > > > > > > > > > > >^ | |
                                > > > > > > > > > > >| |Motor2 |----------*
                                > > > > > > > > > > >| |_______ | ^
                                > > > > > > > > > > >| gear
                                > > > > > > > > > > >bigger gear
                                > > > > > > > > > > >
                                > > > > > > > > > > > the bigger gear is connected to the shaft.
                                > > > > > > > > > > >
                                > > > > > > > > > > >
                                > > > > > > > > > > >(Forgive me for the horrible ASCII art.)
                                > > > > > > > > > > >
                                > > > > > > > > > > >
                                > > > > > > > > > > >
                                > > > > > > > > > > >----- Original Message -----
                                > > > > > > > > > > >From: "Gustavo" <gustavo@...>
                                > > > > > > > > > > >To: <seattlerobotics@yahoogroups.com>
                                > > > > > > > > > > >Sent: Tuesday, August 05, 2003 5:10 AM
                                > > > > > > > > > > >Subject: [SeattleRobotics] Motors and Encoders
                                > > > > > > > > > > >
                                > > > > > > > > > > >
                                > > > > > > > > > > > > Hello,
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > I'm looking for a suitable encoder, and motor
                                (it
                                > > >doesn't
                                > > > > > > > > > > > necessarily have to be a single package) for a
                                > micromouse
                                > > > > > robot. I
                                > > > > > > >have
                                > > > > > > > > > > > tried to salvage optical encoders from computer mice,
                                > but I
                                > > >can't
                                > > > > > > >seem
                                > > > > > > > > >to
                                > > > > > > > > > > > get them coupled on the axles. I have thought of
                                > printing
                                > > >out an
                                > > > > > > >encoder
                                > > > > > > > > > > > on a transparency, but then it would be difficult to
                                > align,
                                > > > > > and it
                                > > > > > > >would
                                > > > > > > > > > > > probably bend. I have also though of just printing out
                                > an
                                > > >encoder
                                > > > > > > >with
                                > > > > > > > > > > > the sectors alternating black and white, but then I
                                face
                                > two
                                > > > > > > >problems,
                                > > > > > > > > > > > the lack of resolution, and precision, and the
                                lighting
                                > > > > > conditions
                                > > > > > > >that
                                > > > > > > > > > > > might affect the reading of the sensor. I don't need a
                                > lot
                                > > >of
                                > > > > > > > > >resolution,
                                > > > > > > > > > > > but at least around 30. as for the actual sensor, I
                                > don't
                                > > >need a
                                > > > > > > > > > > > quadrature because the direction that the motor is
                                going
                                > is
                                > > >not
                                > > > > > > >needed
                                > > > > > > > > >(I
                                > > > > > > > > > > > control the motors, I know the direction I set them).
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > As for the motors, I haven't tried servos, and I
                                > don't
                                > > > > > want to
                                > > > > > > >use
                                > > > > > > > > > > > them for rotations, if I do incorporate servos, it
                                will
                                > be
                                > > >for
                                > > > > > > >rotating
                                > > > > > > > > >a
                                > > > > > > > > > > > "head" with various sensors. I need something with
                                speed
                                > (I
                                > > >would
                                > > > > > > >like
                                > > > > > > > > > > > the mouse to go at about 1 meter per second, or maybe
                                > > >faster)
                                > > > > > > > > > > > > The maximum size for the robot is 16.8 cm. (~6.6
                                > in)
                                > > > > > squared
                                > > > > > > > > > > > because the passage way is 18 cm. (~7 in) and the wall
                                > width
                                > > > > > is 1.2
                                > > > > > > >cm
                                > > > > > > > > > > > (~.47 in). But I would the like the robot to be
                                smaller
                                > than
                                > > > > > that to
                                > > > > > > >be
                                > > > > > > > > > > > able to maneuver easily. The width of the robot is
                                going
                                > to
                                > > > > > have to
                                > > > > > > >be
                                > > > > > > > > >to
                                > > > > > > > > > > > be is around 11 cm (4.4 in) if the base is a square,
                                if
                                > it
                                > > >is a
                                > > > > > > >circle,
                                > > > > > > > > > > > it could be slightly bigger. so the maximum length of
                                > the
                                > > >motors
                                > > > > > > >would
                                > > > > > > > > > > > have to be 5.5 cm (2.2 in) because I don't want to use
                                > and
                                > > > > > external
                                > > > > > > >gear
                                > > > > > > > > > > > train, I cant put the motors side by side, and if the
                                > > >encoder
                                > > > > > is on
                                > > > > > > >the
                                > > > > > > > > > > > shaft of the motor then I can't put and other gears
                                > because
                                > > > > > of the
                                > > > > > > > > > > > spacing in between the gear (each gear can rotate
                                freely
                                > a
                                > > >few
                                > > > > > > >degrees).
                                > > > > > > > > > > > The motor should have a gear train, even if it is
                                > outside in
                                > > > > > a box.
                                > > > > > > > > > > > > I have also though about the possibility of
                                using
                                > > >stepper
                                > > > > > > >motors.
                                > > > > > > > > > > > This way I wouldn't need to use the encoder, unless
                                the
                                > > >wheel
                                > > > > > slips,
                                > > > > > > >or
                                > > > > > > > > > > > the stepper motor looses some steps. But stepper
                                motors
                                > are
                                > > > > > hard to
                                > > > > > > > > >mount
                                > > > > > > > > > > > because most of them have a pinion gear on there
                                shaft,
                                > and
                                > > > > > the ones
                                > > > > > > > > >used
                                > > > > > > > > > > > in old 5 1/4 drives weight too much. But it is
                                something
                                > > >that
                                > > > > > I am
                                > > > > > > > > >considering.
                                > > > > > > > > > > > > I have tried to use a Lego design (I've built
                                Lego
                                > > > > > robots for
                                > > > > > > >2
                                > > > > > > > > > > > years with the Mindstorm line of kits, I've stopped
                                now)
                                > but
                                > > >I
                                > > > > > > >couldn't
                                > > > > > > > > > > > get it to be small enough the Lego gear motors are
                                > really
                                > > > > > good, but
                                > > > > > > >they
                                > > > > > > > > > > > also go slow, and I had a difficult time mounting the
                                > > > > > encoder, so I
                                > > > > > > > > >tried
                                > > > > > > > > > > > to use a gear, but the design wouldn't be small
                                enough.
                                > I
                                > > >then
                                > > > > > > >though
                                > > > > > > > > > > > about the Lego rotation sensor, but its signal is
                                > analog,
                                > > > > > there are
                                > > > > > > >4
                                > > > > > > > > > > > different voltage level, at for different parts of the
                                > > >cycle, but
                                > > > > > > >then
                                > > > > > > > > > > > this would require either a port on the ADC, or 4
                                > > >comparators
                                > > > > > (the
                                > > > > > > >339
                                > > > > > > > > > > > chip) and it would waste 4 I/O pins. AND it would be
                                > > > > > inaccurate for
                                > > > > > > > > >high
                                > > > > > > > > > > > speeds.
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > BTW. this is for my 7th grade science project.
                                > Idea of
                                > > >the
                                > > > > > > >project
                                > > > > > > > > > > > is to identify which algorithm is more efficient, and
                                > faster
                                > > >in
                                > > > > > > >solving
                                > > > > > > > > > > > the maze. I may make the use a different maze then the
                                > ones
                                > > > > > used in
                                > > > > > > > > > > > micromouse compition (maybe less cells, or the
                                beginning
                                > and
                                > > >end
                                > > > > > > > > >location
                                > > > > > > > > > > > is different). I chose this idea because it is more of
                                a
                                > > > > > programming
                                > > > > > > > > > > > project, then a hardware project, and I am better at
                                > > >software
                                > > > > > than
                                > > > > > > > > > > > hardware, I don't really have any mechanical skills,
                                > which
                                > > >is
                                > > > > > why I
                                > > > > > > >want
                                > > > > > > > > > > > to keep the actual motor hardware simple. My dad can
                                > help me
                                > > >with
                                > > > > > > >the
                                > > > > > > > > > > > mechanical aspects of the project.
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > These are some micromouse links if you want more
                                > > > > > information
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > http://micromouse.cannock.ac.uk/
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > http://micromouse.cs.rhbnc.ac.uk/
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > >
                                > >http://www.lboro.ac.uk/departments/el/robotics/micromouseindex.html
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > http://fused.org/projects/
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > http://www.cs.rhul.ac.uk/eca/micromouse/
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > http://www.ece.ucdavis.edu/umouse/
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > And help is appreciated
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > Rgds,
                                > > > > > > > > > > > > Gustavo
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > [Non-text portions of this message have been
                                removed]
                                > > > > > > > > > > > >
                                > > > > > > > > > > > >
                                > > > > > > > > > > > > Visit the SRS Website at
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