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Re: [SeattleRobotics] newbie questions about linear actuators and Arduino controller

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  • Weston Turner
    You can control servos and other actuators directly with the Arduino. There is no need to use an RC transmitter or receiver in the design unless you want to
    Message 1 of 14 , Jul 7, 2011
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      You can control servos and other actuators directly with the Arduino. There is no need to use an RC transmitter or receiver in the design unless you want to drive the cart remotely from a distance (seems dangerous). I assume you want to sit in the cart and drive it with the Wiimote or other joystick device. In any case, to use some kind of human computer interface device to drive the robot, you will need an embedded computer with a Bluetooth and/or usb host controller. Although it would be possible to enable the Arduino to host these devices, it would take significant work (software engineering skills). It would be much easier for you to use an embedded computer to interface with your hand controller, communicate with the Arduino via a serial port on the computer, and control the actuators with the Arduino.

      There are Python and C# projects out there to allow your custom software to talk to Wiimotes, joysticks, PS3 controllers, etc.. All of these are variants of generic human interface devices, but the Wiimote, in particular, requires more unique treatment because it communicates with the computer via Bluetooth, and does not perfectly adhere to HID specifications because it is designed to interface with a Nintendo Wii not a computer. I mention Python and C# because they are high level languages that should be more immediately accessible to you. Here are some example projects that people have developed for controlling actuators with joysticks. These are just a few. If you do a search on the topic, you will get many others.

      Sweet youtube video of a Wiimote controlling a massive robotic arm:
      Arduino Pan/Tilt Platform Controlled with a Wiimote 

      C# Wiimote Library, especially full featured and well written:

      Once you are able to control a small actuator with the Arduino, controlling larger ones -- that can depress the brake pedal or turn the steering wheel -- won't be much different.

      As for your questions regarding feedback and stepper motors, you may want to hold off on addressing these until you have worked out the high level design of your system, and the basics of controlling a generic actuator (small servo) with your hand controller. Ideally, your system should be designed such that you can insert any hand controller (joystick or Wiimote) or any actuator (big or small, rotary or linear) and it will behave in a consistent manner, i.e, the system should be highly modular with implementation details abstracted.

      Weston

      On Thu, Jul 7, 2011 at 11:34 AM, dmacbothell <doug@...> wrote:
       

      I just joined this group in hopes that someone here might be able to shed some light on some questions I have reguarding a project I am working on. It is not really a Robot but uses a lot of the same stuff as a Robot might (I think)
      This might get a little long but woudl rather give more infoo then not enough

      I have a little art car, It is based on an electric Golf Cart shassis. I want ot be able to control it with a joy stick istead of the steerign wheel and pedals.

      What I am thinking is my best option is to have a linear actuator attached to the steerign and a second one for the brake and then using an electronic speed controler hooked to the arduino for the throttle, It woudl also have regen braking so would handle some of the braking.

      A little aboutme, I am good at fabricating things, understand electricity, wiring realys switches etc, I have a basic understanding of computers/pc

      I dont have any experience with the Arduino or programing at all

      I want the linear actuators to mimic the joystick. IE if the joystick moves to the rigth 20%of it travel the steerign linear actuator would move tot he right of center 20%, when the joystick is released it would return to O and so woudl the linear actuator, IE car woudl drive straight

      Throttle and brakes would work the same way

      I found one place that sells linear actuators that they have added a box to to make they work like a servo and you can actually use RC hobby reciever, transmitter with them but I am trying to watch my budget for this so trying to use what I have which are linear actuators with potentiometers and without the "servo box"

      My questions are this
      1 Can the ARduino interface directly with a linear actuator and the pot or does it need somesort of box inbetween.

      2 If I dont use linear actuators with pots can I use a magnetic referance sensor for feedback?

      3 I want ot use a Wii Numchuck for the joystick rather then start from scratch, Any advice on how to do this?

      4 Should I just buck up the money and buy everythingoff the shelf or shoudl this work just as well?

      5 What about programming for this, I have found lots of programs but nothing that is quite what I am looking for but have not spent a ton of time searching yet

      6 Someone suggested using stepper motors for this instead, what are your thoughts

      Sorry to be so long winded but giving more details up front makes sense to me

      Thanks in advance to all who take the time to read all this and reply with words of advice
      Doug


    • Rob Purdy
      You trying to R/C this or just an alternative control? Linear actuators are easy to R/C but they tend to be slow. Rob To: SeattleRobotics@yahoogroups.com From:
      Message 2 of 14 , Jul 7, 2011
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        You trying to R/C this or just an alternative control?
        Linear actuators are easy to R/C but they tend to be slow.
         
         
        Rob 

        To: SeattleRobotics@yahoogroups.com
        From: doug@...
        Date: Thu, 7 Jul 2011 18:34:28 +0000
        Subject: [SeattleRobotics] newbie questions about linear actuators and Arduino controller

         
        I just joined this group in hopes that someone here might be able to shed some light on some questions I have reguarding a project I am working on. It is not really a Robot but uses a lot of the same stuff as a Robot might (I think)
        This might get a little long but woudl rather give more infoo then not enough

        I have a little art car, It is based on an electric Golf Cart shassis. I want ot be able to control it with a joy stick istead of the steerign wheel and pedals.

        What I am thinking is my best option is to have a linear actuator attached to the steerign and a second one for the brake and then using an electronic speed controler hooked to the arduino for the throttle, It woudl also have regen braking so would handle some of the braking.

        A little aboutme, I am good at fabricating things, understand electricity, wiring realys switches etc, I have a basic understanding of computers/pc

        I dont have any experience with the Arduino or programing at all

        I want the linear actuators to mimic the joystick. IE if the joystick moves to the rigth 20%of it travel the steerign linear actuator would move tot he right of center 20%, when the joystick is released it would return to O and so woudl the linear actuator, IE car woudl drive straight

        Throttle and brakes would work the same way

        I found one place that sells linear actuators that they have added a box to to make they work like a servo and you can actually use RC hobby reciever, transmitter with them but I am trying to watch my budget for this so trying to use what I have which are linear actuators with potentiometers and without the "servo box"

        My questions are this
        1 Can the ARduino interface directly with a linear actuator and the pot or does it need somesort of box inbetween.

        2 If I dont use linear actuators with pots can I use a magnetic referance sensor for feedback?

        3 I want ot use a Wii Numchuck for the joystick rather then start from scratch, Any advice on how to do this?

        4 Should I just buck up the money and buy everythingoff the shelf or shoudl this work just as well?

        5 What about programming for this, I have found lots of programs but nothing that is quite what I am looking for but have not spent a ton of time searching yet

        6 Someone suggested using stepper motors for this instead, what are your thoughts

        Sorry to be so long winded but giving more details up front makes sense to me

        Thanks in advance to all who take the time to read all this and reply with words of advice
        Doug


      • Weston Turner
        PS: To present a generic interface to larger actuators that do not have integrated drive/position control circuitry, you will need to build custom driver/
        Message 3 of 14 , Jul 8, 2011
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          PS: To present a generic interface to larger actuators that do not have integrated drive/position control circuitry, you will need to build custom driver/ position control circuits (the intermediate black box you speak of). The Arduino will only put out logic level control signals such as PWM, pulseout, etc., then the power drive circuit will drive the actuator, and the control circuit will handle feedback for position control, and faults such as over-current. If you want PID control or more sophisticated control over your actuators, the appropriate place to handle this would be in the custom driver/control module with a microcontroller or some type of analog control circuit. In reality, there are many ways to design this type of system, This is why I am being intentionally high level and vague.

          Weston

          On Thu, Jul 7, 2011 at 11:48 PM, Rob Purdy <kb7wnz@...> wrote:
           

          You trying to R/C this or just an alternative control?
          Linear actuators are easy to R/C but they tend to be slow.
           
           
          Rob 

          To: SeattleRobotics@yahoogroups.com
          From: doug@...
          Date: Thu, 7 Jul 2011 18:34:28 +0000
          Subject: [SeattleRobotics] newbie questions about linear actuators and Arduino controller


           
          I just joined this group in hopes that someone here might be able to shed some light on some questions I have reguarding a project I am working on. It is not really a Robot but uses a lot of the same stuff as a Robot might (I think)
          This might get a little long but woudl rather give more infoo then not enough

          I have a little art car, It is based on an electric Golf Cart shassis. I want ot be able to control it with a joy stick istead of the steerign wheel and pedals.

          What I am thinking is my best option is to have a linear actuator attached to the steerign and a second one for the brake and then using an electronic speed controler hooked to the arduino for the throttle, It woudl also have regen braking so would handle some of the braking.

          A little aboutme, I am good at fabricating things, understand electricity, wiring realys switches etc, I have a basic understanding of computers/pc

          I dont have any experience with the Arduino or programing at all

          I want the linear actuators to mimic the joystick. IE if the joystick moves to the rigth 20%of it travel the steerign linear actuator would move tot he right of center 20%, when the joystick is released it would return to O and so woudl the linear actuator, IE car woudl drive straight

          Throttle and brakes would work the same way

          I found one place that sells linear actuators that they have added a box to to make they work like a servo and you can actually use RC hobby reciever, transmitter with them but I am trying to watch my budget for this so trying to use what I have which are linear actuators with potentiometers and without the "servo box"

          My questions are this
          1 Can the ARduino interface directly with a linear actuator and the pot or does it need somesort of box inbetween.

          2 If I dont use linear actuators with pots can I use a magnetic referance sensor for feedback?

          3 I want ot use a Wii Numchuck for the joystick rather then start from scratch, Any advice on how to do this?

          4 Should I just buck up the money and buy everythingoff the shelf or shoudl this work just as well?

          5 What about programming for this, I have found lots of programs but nothing that is quite what I am looking for but have not spent a ton of time searching yet

          6 Someone suggested using stepper motors for this instead, what are your thoughts

          Sorry to be so long winded but giving more details up front makes sense to me

          Thanks in advance to all who take the time to read all this and reply with words of advice
          Doug



        • David Buckley
          Go the RC route and pay thee money otherwise you are in for a very very steep learning curve especially if you want to use the HArduino, programming and
          Message 4 of 14 , Jul 8, 2011
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            Go the RC route and pay thee money otherwise you are in for a very very steep learning curve especially if you want to use the HArduino, programming and Nunchuck.
            Even going the off-the-shelf-RC route it is going to be a steep learning curve.
             
            DAvid
             
             
             
             
            To: SeattleRobotics@yahoogroups.com
            From: doug@...
            Date: Thu, 7 Jul 2011 18:34:28 +0000
            Subject: [SeattleRobotics] newbie questions about linear actuators and Arduino controller


             
            I just joined this group in hopes that someone here might be able to shed some light on some questions I have reguarding a project I am working on. It is not really a Robot but uses a lot of the same stuff as a Robot might (I think)
            This might get a little long but woudl rather give more infoo then not enough

            I have a little art car, It is based on an electric Golf Cart shassis. I want ot be able to control it with a joy stick istead of the steerign wheel and pedals.

            What I am thinking is my best option is to have a linear actuator attached to the steerign and a second one for the brake and then using an electronic speed controler hooked to the arduino for the throttle, It woudl also have regen braking so would handle some of the braking.

            A little aboutme, I am good at fabricating things, understand electricity, wiring realys switches etc, I have a basic understanding of computers/pc

            I dont have any experience with the Arduino or programing at all

            I want the linear actuators to mimic the joystick. IE if the joystick moves to the rigth 20%of it travel the steerign linear actuator would move tot he right of center 20%, when the joystick is released it would return to O and so woudl the linear actuator, IE car woudl drive straight

            Throttle and brakes would work the same way

            I found one place that sells linear actuators that they have added a box to to make they work like a servo and you can actually use RC hobby reciever, transmitter with them but I am trying to watch my budget for this so trying to use what I have which are linear actuators with potentiometers and without the "servo box"

            My questions are this
            1 Can the ARduino interface directly with a linear actuator and the pot or does it need somesort of box inbetween.

            2 If I dont use linear actuators with pots can I use a magnetic referance sensor for feedback?

            3 I want ot use a Wii Numchuck for the joystick rather then start from scratch, Any advice on how to do this?

            4 Should I just buck up the money and buy everythingoff the shelf or shoudl this work just as well?

            5 What about programming for this, I have found lots of programs but nothing that is quite what I am looking for but have not spent a ton of time searching yet

            6 Someone suggested using stepper motors for this instead, what are your thoughts

            Sorry to be so long winded but giving more details up front makes sense to me

            Thanks in advance to all who take the time to read all this and reply with words of advice
            Doug



          • David Buckley
            Arduino Pan/Tilt Platform Controlled with a Wiimote http://www.westy92.com/?p=24 COMPLETE WITH MALWARE - Shopper Reports - XvidSetup.exe !!!! DAvid ...
            Message 5 of 14 , Jul 8, 2011
            • 0 Attachment
              Arduino Pan/Tilt Platform Controlled with a Wiimote 
              COMPLETE WITH MALWARE - Shopper Reports - XvidSetup.exe     !!!!
               
              DAvid
               
              ----- Original Message -----
              Sent: Friday, July 08, 2011 7:46 AM
              Subject: Re: [SeattleRobotics] newbie questions about linear actuators and Arduino controller

               

              You can control servos and other actuators directly with the Arduino. There is no need to use an RC transmitter or receiver in the design unless you want to drive the cart remotely from a distance (seems dangerous). I assume you want to sit in the cart and drive it with the Wiimote or other joystick device. In any case, to use some kind of human computer interface device to drive the robot, you will need an embedded computer with a Bluetooth and/or usb host controller. Although it would be possible to enable the Arduino to host these devices, it would take significant work (software engineering skills). It would be much easier for you to use an embedded computer to interface with your hand controller, communicate with the Arduino via a serial port on the computer, and control the actuators with the Arduino.


              There are Python and C# projects out there to allow your custom software to talk to Wiimotes, joysticks, PS3 controllers, etc.. All of these are variants of generic human interface devices, but the Wiimote, in particular, requires more unique treatment because it communicates with the computer via Bluetooth, and does not perfectly adhere to HID specifications because it is designed to interface with a Nintendo Wii not a computer. I mention Python and C# because they are high level languages that should be more immediately accessible to you. Here are some example projects that people have developed for controlling actuators with joysticks. These are just a few. If you do a search on the topic, you will get many others.

              Sweet youtube video of a Wiimote controlling a massive robotic arm:
              Arduino Pan/Tilt Platform Controlled with a Wiimote 

              C# Wiimote Library, especially full featured and well written:

              Once you are able to control a small actuator with the Arduino, controlling larger ones -- that can depress the brake pedal or turn the steering wheel -- won't be much different.

              As for your questions regarding feedback and stepper motors, you may want to hold off on addressing these until you have worked out the high level design of your system, and the basics of controlling a generic actuator (small servo) with your hand controller. Ideally, your system should be designed such that you can insert any hand controller (joystick or Wiimote) or any actuator (big or small, rotary or linear) and it will behave in a consistent manner, i.e, the system should be highly modular with implementation details abstracted.

              Weston

              On Thu, Jul 7, 2011 at 11:34 AM, dmacbothell <doug@...> wrote:
               

              I just joined this group in hopes that someone here might be able to shed some light on some questions I have reguarding a project I am working on. It is not really a Robot but uses a lot of the same stuff as a Robot might (I think)
              This might get a little long but woudl rather give more infoo then not enough

              I have a little art car, It is based on an electric Golf Cart shassis. I want ot be able to control it with a joy stick istead of the steerign wheel and pedals.

              What I am thinking is my best option is to have a linear actuator attached to the steerign and a second one for the brake and then using an electronic speed controler hooked to the arduino for the throttle, It woudl also have regen braking so would handle some of the braking.

              A little aboutme, I am good at fabricating things, understand electricity, wiring realys switches etc, I have a basic understanding of computers/pc

              I dont have any experience with the Arduino or programing at all

              I want the linear actuators to mimic the joystick. IE if the joystick moves to the rigth 20%of it travel the steerign linear actuator would move tot he right of center 20%, when the joystick is released it would return to O and so woudl the linear actuator, IE car woudl drive straight

              Throttle and brakes would work the same way

              I found one place that sells linear actuators that they have added a box to to make they work like a servo and you can actually use RC hobby reciever, transmitter with them but I am trying to watch my budget for this so trying to use what I have which are linear actuators with potentiometers and without the "servo box"

              My questions are this
              1 Can the ARduino interface directly with a linear actuator and the pot or does it need somesort of box inbetween.

              2 If I dont use linear actuators with pots can I use a magnetic referance sensor for feedback?

              3 I want ot use a Wii Numchuck for the joystick rather then start from scratch, Any advice on how to do this?

              4 Should I just buck up the money and buy everythingoff the shelf or shoudl this work just as well?

              5 What about programming for this, I have found lots of programs but nothing that is quite what I am looking for but have not spent a ton of time searching yet

              6 Someone suggested using stepper motors for this instead, what are your thoughts

              Sorry to be so long winded but giving more details up front makes sense to me

              Thanks in advance to all who take the time to read all this and reply with words of advice
              Doug


            • Weston Turner
              I run Ubuntu, what is malware? :) Weston
              Message 6 of 14 , Jul 8, 2011
              • 0 Attachment
                I run Ubuntu, what is malware? :)

                Weston

                On Fri, Jul 8, 2011 at 7:15 AM, David Buckley <david@...> wrote:
                 

                Arduino Pan/Tilt Platform Controlled with a Wiimote 
                COMPLETE WITH MALWARE - Shopper Reports - XvidSetup.exe     !!!!
                 
                DAvid
                 
                ----- Original Message -----
                Sent: Friday, July 08, 2011 7:46 AM
                Subject: Re: [SeattleRobotics] newbie questions about linear actuators and Arduino controller

                 

                You can control servos and other actuators directly with the Arduino. There is no need to use an RC transmitter or receiver in the design unless you want to drive the cart remotely from a distance (seems dangerous). I assume you want to sit in the cart and drive it with the Wiimote or other joystick device. In any case, to use some kind of human computer interface device to drive the robot, you will need an embedded computer with a Bluetooth and/or usb host controller. Although it would be possible to enable the Arduino to host these devices, it would take significant work (software engineering skills). It would be much easier for you to use an embedded computer to interface with your hand controller, communicate with the Arduino via a serial port on the computer, and control the actuators with the Arduino.


                There are Python and C# projects out there to allow your custom software to talk to Wiimotes, joysticks, PS3 controllers, etc.. All of these are variants of generic human interface devices, but the Wiimote, in particular, requires more unique treatment because it communicates with the computer via Bluetooth, and does not perfectly adhere to HID specifications because it is designed to interface with a Nintendo Wii not a computer. I mention Python and C# because they are high level languages that should be more immediately accessible to you. Here are some example projects that people have developed for controlling actuators with joysticks. These are just a few. If you do a search on the topic, you will get many others.

                Sweet youtube video of a Wiimote controlling a massive robotic arm:
                Arduino Pan/Tilt Platform Controlled with a Wiimote 

                C# Wiimote Library, especially full featured and well written:

                Once you are able to control a small actuator with the Arduino, controlling larger ones -- that can depress the brake pedal or turn the steering wheel -- won't be much different.

                As for your questions regarding feedback and stepper motors, you may want to hold off on addressing these until you have worked out the high level design of your system, and the basics of controlling a generic actuator (small servo) with your hand controller. Ideally, your system should be designed such that you can insert any hand controller (joystick or Wiimote) or any actuator (big or small, rotary or linear) and it will behave in a consistent manner, i.e, the system should be highly modular with implementation details abstracted.

                Weston

                On Thu, Jul 7, 2011 at 11:34 AM, dmacbothell <doug@...> wrote:
                 

                I just joined this group in hopes that someone here might be able to shed some light on some questions I have reguarding a project I am working on. It is not really a Robot but uses a lot of the same stuff as a Robot might (I think)
                This might get a little long but woudl rather give more infoo then not enough

                I have a little art car, It is based on an electric Golf Cart shassis. I want ot be able to control it with a joy stick istead of the steerign wheel and pedals.

                What I am thinking is my best option is to have a linear actuator attached to the steerign and a second one for the brake and then using an electronic speed controler hooked to the arduino for the throttle, It woudl also have regen braking so would handle some of the braking.

                A little aboutme, I am good at fabricating things, understand electricity, wiring realys switches etc, I have a basic understanding of computers/pc

                I dont have any experience with the Arduino or programing at all

                I want the linear actuators to mimic the joystick. IE if the joystick moves to the rigth 20%of it travel the steerign linear actuator would move tot he right of center 20%, when the joystick is released it would return to O and so woudl the linear actuator, IE car woudl drive straight

                Throttle and brakes would work the same way

                I found one place that sells linear actuators that they have added a box to to make they work like a servo and you can actually use RC hobby reciever, transmitter with them but I am trying to watch my budget for this so trying to use what I have which are linear actuators with potentiometers and without the "servo box"

                My questions are this
                1 Can the ARduino interface directly with a linear actuator and the pot or does it need somesort of box inbetween.

                2 If I dont use linear actuators with pots can I use a magnetic referance sensor for feedback?

                3 I want ot use a Wii Numchuck for the joystick rather then start from scratch, Any advice on how to do this?

                4 Should I just buck up the money and buy everythingoff the shelf or shoudl this work just as well?

                5 What about programming for this, I have found lots of programs but nothing that is quite what I am looking for but have not spent a ton of time searching yet

                6 Someone suggested using stepper motors for this instead, what are your thoughts

                Sorry to be so long winded but giving more details up front makes sense to me

                Thanks in advance to all who take the time to read all this and reply with words of advice
                Doug



              • David Buckley
                Stuff you really don t want on your computer, not as bad as viruses etc, but still stuff you don t want which gets there by appearing to be something else.
                Message 7 of 14 , Jul 8, 2011
                • 0 Attachment
                  Stuff you really don't want on your computer, not as bad as viruses etc, but still stuff you don't want which gets there by appearing to be something else.
                  DAvid
                  .
                  ----- Original Message -----
                  Sent: Friday, July 08, 2011 3:26 PM
                  Subject: Re: [SeattleRobotics] newbie questions about linear actuators and Arduino controller

                   

                  I run Ubuntu, what is malware? :)


                  Weston

                  On Fri, Jul 8, 2011 at 7:15 AM, David Buckley <david@...> wrote:
                   

                  Arduino Pan/Tilt Platform Controlled with a Wiimote 
                  COMPLETE WITH MALWARE - Shopper Reports - XvidSetup.exe     !!!!
                   
                  DAvid
                   
                  ----- Original Message -----
                  Sent: Friday, July 08, 2011 7:46 AM
                  Subject: Re: [SeattleRobotics] newbie questions about linear actuators and Arduino controller

                   

                  You can control servos and other actuators directly with the Arduino. There is no need to use an RC transmitter or receiver in the design unless you want to drive the cart remotely from a distance (seems dangerous). I assume you want to sit in the cart and drive it with the Wiimote or other joystick device. In any case, to use some kind of human computer interface device to drive the robot, you will need an embedded computer with a Bluetooth and/or usb host controller. Although it would be possible to enable the Arduino to host these devices, it would take significant work (software engineering skills). It would be much easier for you to use an embedded computer to interface with your hand controller, communicate with the Arduino via a serial port on the computer, and control the actuators with the Arduino.


                  There are Python and C# projects out there to allow your custom software to talk to Wiimotes, joysticks, PS3 controllers, etc.. All of these are variants of generic human interface devices, but the Wiimote, in particular, requires more unique treatment because it communicates with the computer via Bluetooth, and does not perfectly adhere to HID specifications because it is designed to interface with a Nintendo Wii not a computer. I mention Python and C# because they are high level languages that should be more immediately accessible to you. Here are some example projects that people have developed for controlling actuators with joysticks. These are just a few. If you do a search on the topic, you will get many others.

                  Sweet youtube video of a Wiimote controlling a massive robotic arm:
                  Arduino Pan/Tilt Platform Controlled with a Wiimote 

                  C# Wiimote Library, especially full featured and well written:

                  Once you are able to control a small actuator with the Arduino, controlling larger ones -- that can depress the brake pedal or turn the steering wheel -- won't be much different.

                  As for your questions regarding feedback and stepper motors, you may want to hold off on addressing these until you have worked out the high level design of your system, and the basics of controlling a generic actuator (small servo) with your hand controller. Ideally, your system should be designed such that you can insert any hand controller (joystick or Wiimote) or any actuator (big or small, rotary or linear) and it will behave in a consistent manner, i.e, the system should be highly modular with implementation details abstracted.

                  Weston

                  On Thu, Jul 7, 2011 at 11:34 AM, dmacbothell <doug@...> wrote:
                   

                  I just joined this group in hopes that someone here might be able to shed some light on some questions I have reguarding a project I am working on. It is not really a Robot but uses a lot of the same stuff as a Robot might (I think)
                  This might get a little long but woudl rather give more infoo then not enough

                  I have a little art car, It is based on an electric Golf Cart shassis. I want ot be able to control it with a joy stick istead of the steerign wheel and pedals.

                  What I am thinking is my best option is to have a linear actuator attached to the steerign and a second one for the brake and then using an electronic speed controler hooked to the arduino for the throttle, It woudl also have regen braking so would handle some of the braking.

                  A little aboutme, I am good at fabricating things, understand electricity, wiring realys switches etc, I have a basic understanding of computers/pc

                  I dont have any experience with the Arduino or programing at all

                  I want the linear actuators to mimic the joystick. IE if the joystick moves to the rigth 20%of it travel the steerign linear actuator would move tot he right of center 20%, when the joystick is released it would return to O and so woudl the linear actuator, IE car woudl drive straight

                  Throttle and brakes would work the same way

                  I found one place that sells linear actuators that they have added a box to to make they work like a servo and you can actually use RC hobby reciever, transmitter with them but I am trying to watch my budget for this so trying to use what I have which are linear actuators with potentiometers and without the "servo box"

                  My questions are this
                  1 Can the ARduino interface directly with a linear actuator and the pot or does it need somesort of box inbetween.

                  2 If I dont use linear actuators with pots can I use a magnetic referance sensor for feedback?

                  3 I want ot use a Wii Numchuck for the joystick rather then start from scratch, Any advice on how to do this?

                  4 Should I just buck up the money and buy everythingoff the shelf or shoudl this work just as well?

                  5 What about programming for this, I have found lots of programs but nothing that is quite what I am looking for but have not spent a ton of time searching yet

                  6 Someone suggested using stepper motors for this instead, what are your thoughts

                  Sorry to be so long winded but giving more details up front makes sense to me

                  Thanks in advance to all who take the time to read all this and reply with words of advice
                  Doug



                • Joe Justice
                  We have some linear actuators for programmatic control of parts of are car, see www.WIKISPEED.com for some more on that. Our shop is in Shoreline, WA, and we
                  Message 8 of 14 , Jul 8, 2011
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                    We have some linear actuators for programmatic control of parts of are car, see www.WIKISPEED.com for some more on that. Our shop is in Shoreline, WA, and we could show you how we've implemented them.

                    Also, Tyler Folsom has an electric recumbent bicycle that is being converted to steer and brake by wire for full joystick control. Last I saw it the bicycle was very far along and he may be finished by now. He is in the Ravenna neighborhood of Seattle.

                    Best, please post pictures and discoveries of your project as it moves along!
                    -Joe Justice
                  • Doug MacAulay
                    Weston. Thanks for your reply. I may not have been clear, The Wii controller I want to use is hard wired, I did not want to go wireless. I was going to use the
                    Message 9 of 14 , Jul 8, 2011
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                      Weston.

                      Thanks for your reply. I may not have been clear, The Wii controller I want to use is hard wired, I did not want to go wireless. I was going to use the Wii Numchuck because it has the joy stick and two other buttons I need and it is fairly cheap and readily available.  So I would think that would eliminate the need for the Bluetooth part of things. I am just beginning to research the Arduino stuff. But was hoping to find an easy answer from someone that had already done something similar. And how they had done it and what had worked for them and what problems they had. Since I am so new to this and not well versed in computers

                       

                      Doug MacAulay

                      Autovice Import Parts and Service

                      AKA

                      BOWWOW Import Parts and Service

                      2200 196 th ST SW

                      Lynnwood WA 98036

                      425-672-4366

                      AUTOVICESERVICE.COM

                       

                      From: SeattleRobotics@yahoogroups.com [mailto:SeattleRobotics@yahoogroups.com] On Behalf Of Weston Turner
                      Sent: Thursday, July 07, 2011 11:46 PM
                      To: SeattleRobotics@yahoogroups.com
                      Subject: Re: [SeattleRobotics] newbie questions about linear actuators and Arduino controller

                       

                       

                      You can control servos and other actuators directly with the Arduino. There is no need to use an RC transmitter or receiver in the design unless you want to drive the cart remotely from a distance (seems dangerous). I assume you want to sit in the cart and drive it with the Wiimote or other joystick device. In any case, to use some kind of human computer interface device to drive the robot, you will need an embedded computer with a Bluetooth and/or usb host controller. Although it would be possible to enable the Arduino to host these devices, it would take significant work (software engineering skills). It would be much easier for you to use an embedded computer to interface with your hand controller, communicate with the Arduino via a serial port on the computer, and control the actuators with the Arduino.

                       

                      There are Python and C# projects out there to allow your custom software to talk to Wiimotes, joysticks, PS3 controllers, etc.. All of these are variants of generic human interface devices, but the Wiimote, in particular, requires more unique treatment because it communicates with the computer via Bluetooth, and does not perfectly adhere to HID specifications because it is designed to interface with a Nintendo Wii not a computer. I mention Python and C# because they are high level languages that should be more immediately accessible to you. Here are some example projects that people have developed for controlling actuators with joysticks. These are just a few. If you do a search on the topic, you will get many others.

                       

                      Sweet youtube video of a Wiimote controlling a massive robotic arm:

                      Arduino Pan/Tilt Platform Controlled with a Wiimote 

                       

                      C# Wiimote Library, especially full featured and well written:

                       

                      Once you are able to control a small actuator with the Arduino, controlling larger ones -- that can depress the brake pedal or turn the steering wheel -- won't be much different.

                       

                      As for your questions regarding feedback and stepper motors, you may want to hold off on addressing these until you have worked out the high level design of your system, and the basics of controlling a generic actuator (small servo) with your hand controller. Ideally, your system should be designed such that you can insert any hand controller (joystick or Wiimote) or any actuator (big or small, rotary or linear) and it will behave in a consistent manner, i.e, the system should be highly modular with implementation details abstracted.

                       

                      Weston

                       

                      On Thu, Jul 7, 2011 at 11:34 AM, dmacbothell <doug@...> wrote:

                       

                      I just joined this group in hopes that someone here might be able to shed some light on some questions I have reguarding a project I am working on. It is not really a Robot but uses a lot of the same stuff as a Robot might (I think)
                      This might get a little long but woudl rather give more infoo then not enough

                      I have a little art car, It is based on an electric Golf Cart shassis. I want ot be able to control it with a joy stick istead of the steerign wheel and pedals.

                      What I am thinking is my best option is to have a linear actuator attached to the steerign and a second one for the brake and then using an electronic speed controler hooked to the arduino for the throttle, It woudl also have regen braking so would handle some of the braking.

                      A little aboutme, I am good at fabricating things, understand electricity, wiring realys switches etc, I have a basic understanding of computers/pc

                      I dont have any experience with the Arduino or programing at all

                      I want the linear actuators to mimic the joystick. IE if the joystick moves to the rigth 20%of it travel the steerign linear actuator would move tot he right of center 20%, when the joystick is released it would return to O and so woudl the linear actuator, IE car woudl drive straight

                      Throttle and brakes would work the same way

                      I found one place that sells linear actuators that they have added a box to to make they work like a servo and you can actually use RC hobby reciever, transmitter with them but I am trying to watch my budget for this so trying to use what I have which are linear actuators with potentiometers and without the "servo box"

                      My questions are this
                      1 Can the ARduino interface directly with a linear actuator and the pot or does it need somesort of box inbetween.

                      2 If I dont use linear actuators with pots can I use a magnetic referance sensor for feedback?

                      3 I want ot use a Wii Numchuck for the joystick rather then start from scratch, Any advice on how to do this?

                      4 Should I just buck up the money and buy everythingoff the shelf or shoudl this work just as well?

                      5 What about programming for this, I have found lots of programs but nothing that is quite what I am looking for but have not spent a ton of time searching yet

                      6 Someone suggested using stepper motors for this instead, what are your thoughts

                      Sorry to be so long winded but giving more details up front makes sense to me

                      Thanks in advance to all who take the time to read all this and reply with words of advice
                      Doug

                       

                    • dmacbothell
                      I am just looking for an altrenative control, not RC,Thanks, I should have been clear on this
                      Message 10 of 14 , Jul 8, 2011
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                        I am just looking for an altrenative control, not RC,Thanks, I should have been clear on this


                        --- In SeattleRobotics@yahoogroups.com, Rob Purdy <kb7wnz@...> wrote:
                        >
                        >
                        > You trying to R/C this or just an alternative control?
                        > Linear actuators are easy to R/C but they tend to be slow.
                        >
                        >
                        > Rob
                        >
                        >
                        >
                        > To: SeattleRobotics@yahoogroups.com
                        > From: doug@...
                        > Date: Thu, 7 Jul 2011 18:34:28 +0000
                        > Subject: [SeattleRobotics] newbie questions about linear actuators and Arduino controller
                        >
                        >
                        >
                        >
                        >
                        >
                        > I just joined this group in hopes that someone here might be able to shed some light on some questions I have reguarding a project I am working on. It is not really a Robot but uses a lot of the same stuff as a Robot might (I think)
                        > This might get a little long but woudl rather give more infoo then not enough
                        >
                        > I have a little art car, It is based on an electric Golf Cart shassis. I want ot be able to control it with a joy stick istead of the steerign wheel and pedals.
                        >
                        > What I am thinking is my best option is to have a linear actuator attached to the steerign and a second one for the brake and then using an electronic speed controler hooked to the arduino for the throttle, It woudl also have regen braking so would handle some of the braking.
                        >
                        > A little aboutme, I am good at fabricating things, understand electricity, wiring realys switches etc, I have a basic understanding of computers/pc
                        >
                        > I dont have any experience with the Arduino or programing at all
                        >
                        > I want the linear actuators to mimic the joystick. IE if the joystick moves to the rigth 20%of it travel the steerign linear actuator would move tot he right of center 20%, when the joystick is released it would return to O and so woudl the linear actuator, IE car woudl drive straight
                        >
                        > Throttle and brakes would work the same way
                        >
                        > I found one place that sells linear actuators that they have added a box to to make they work like a servo and you can actually use RC hobby reciever, transmitter with them but I am trying to watch my budget for this so trying to use what I have which are linear actuators with potentiometers and without the "servo box"
                        >
                        > My questions are this
                        > 1 Can the ARduino interface directly with a linear actuator and the pot or does it need somesort of box inbetween.
                        >
                        > 2 If I dont use linear actuators with pots can I use a magnetic referance sensor for feedback?
                        >
                        > 3 I want ot use a Wii Numchuck for the joystick rather then start from scratch, Any advice on how to do this?
                        >
                        > 4 Should I just buck up the money and buy everythingoff the shelf or shoudl this work just as well?
                        >
                        > 5 What about programming for this, I have found lots of programs but nothing that is quite what I am looking for but have not spent a ton of time searching yet
                        >
                        > 6 Someone suggested using stepper motors for this instead, what are your thoughts
                        >
                        > Sorry to be so long winded but giving more details up front makes sense to me
                        >
                        > Thanks in advance to all who take the time to read all this and reply with words of advice
                        > Doug
                        >
                      • Alan
                        A $20 PS2 and xcvr module from LM would get you there wireless. Talk to the xcvr with SPI. Alan KM6VV On Behalf Of Doug MacAulay Weston. Thanks for your
                        Message 11 of 14 , Jul 8, 2011
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                          A $20 PS2 and xcvr module from LM would get you there wireless.  Talk to the xcvr with SPI.

                           

                          Alan  KM6VV

                           

                          On Behalf Of Doug MacAulay

                          Weston.

                          Thanks for your reply. I may not have been clear, The Wii controller I want to use is hard wired, I did not want to go wireless. I was going to use the Wii Numchuck because it has the joy stick and two other buttons I need and it is fairly cheap and readily available.  So I would think that would eliminate the need for the Bluetooth part of things. I am just beginning to research the Arduino stuff. But was hoping to find an easy answer from someone that had already done something similar. And how they had done it and what had worked for them and what problems they had. Since I am so new to this and not well versed in computers

                           

                          Doug MacAulay

                        • dmacbothell
                          WOW Thanks fo rall the advice and comments. I really apreciate them. To answer some of the questions and info I forgot to post. To sum it all up, I am looking
                          Message 12 of 14 , Jul 8, 2011
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                            WOW Thanks fo rall the advice and comments. I really apreciate them. To answer some of the questions and info I forgot to post. To sum it all up,
                            I am looking for an laternate type of control, wired joystick

                            I have linear actuators without pots in them but can get ones with pots fairly inexpensively $100 to $125 each compared to the Servo actuators for $300 each form Servocity

                            An altenative solution that was mentioned to me was a "non contact magnetic referance sensor" that shoudl work with tha arduino and my existing linear actuators and they are cheap

                            I am not looking for a great deal of acuracy. If i move the joystick 10% to the left and the linear actuator over shoots it by a couple of degrees it is ok, it does nto have to be precision in the control

                            This is how I thick it could work but really dont know
                            If the joy stick has a range of 0 to 5K on each axis and the nuetral postion being 2.5K and lets say I use pots for position on the linear actuators has the same range and nuetral postion. when the arduino sees any input other then 2.5k +- 200 it would send power to the actuator, probably thru relays to move it till it sees the same value as the input +- 200 (or what ever variation makes it the most drivable) and shuts off the power to the linear actuator till it sees a change in the input. I will probably need to have some sort of margin of error so it is drivable easily without it being twitchy.

                            As far as buying the off the shelf servo linear actuators with the control boxes, for $300 each, that would work fine if using a wireless remote. But I am hoping that either my linear actuators with the magnetic sensors or buying new linear actuators with pots on them for about $125 each can work just as well

                            The other issue I am trying to figure out is that I am converting the car form a mechanical speed controler to an electronic speed controler, The Electronic speed controler wants to see a resistance of 0 to 5k. I would like to have the forward / reverse axis of the joystick control the speed controler when moved forward and teh linear actuator for the brakes when moved backwards, I would think that this should be fairly easy to do withthe Arduino but not sure

                            I also need to have somesort of micro switchthat says the brakes are off all the way before aplling throttle, since the linear actuator will move slower then the joystick and Idont want to have the motor fighting the brakes

                            Once again thanks for all the great advice, questions and info
                            Doug

                            --- In SeattleRobotics@yahoogroups.com, Joe Justice <kiwikungfu@...> wrote:
                            >
                            > We have some linear actuators for programmatic control of parts of are car,
                            > see www.WIKISPEED.com for some more on that. Our shop is in Shoreline, WA,
                            > and we could show you how we've implemented them.
                            >
                            > Also, Tyler Folsom has an electric recumbent bicycle that is being converted
                            > to steer and brake by wire for full joystick control. Last I saw it the
                            > bicycle was very far along and he may be finished by now. He is in the
                            > Ravenna neighborhood of Seattle.
                            >
                            > Best, please post pictures and discoveries of your project as it moves
                            > along!
                            > -Joe Justice
                            > www.facebook.com/WIKISPEED
                            >
                          • Weston Turner
                            Oh yes, using the nunchuk alone (without the Wiimote) would greatly simplify the design. It uses a 400 kHz I2C protocall and the Arduino should support that. I
                            Message 13 of 14 , Jul 8, 2011
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                              Oh yes, using the nunchuk alone (without the Wiimote) would greatly simplify the design. It uses a 400 kHz I2C protocall and the Arduino should support that. I have never interfaced a microcontroller directly to the nunchuk, but its data layer is probably well specified.


                              To electronically controll the resistance seen by the throttle input of your speed controller, you could probably use a digital potentiometer. They have limitations, so if you use one make sure it is compatible with the voltage and current requirements of the speed controller's throttle input.


                              To control the brakes, you probably want to study a little control theory. I'm speaking from intuition when I claim that usually automotive brakes are non linear in their amount of stopping power versus the position of the brake pedal. But I'd say they are more linear in their stopping power versus the force applied to the brake pedal. You may want to think about controlling the brake actuator in terms of force applied to the brake pedal rather than the position of the pedal. You could do this with a pressure sensor of some kind. 

                              Anyone with experience interfacing actuators to a mechanical breaking system care to shed light on the subject?

                              Weston

                              On Fri, Jul 8, 2011 at 2:37 PM, dmacbothell <doug@...> wrote:
                               


                              WOW Thanks fo rall the advice and comments. I really apreciate them. To answer some of the questions and info I forgot to post. To sum it all up,
                              I am looking for an laternate type of control, wired joystick

                              I have linear actuators without pots in them but can get ones with pots fairly inexpensively $100 to $125 each compared to the Servo actuators for $300 each form Servocity

                              An altenative solution that was mentioned to me was a "non contact magnetic referance sensor" that shoudl work with tha arduino and my existing linear actuators and they are cheap

                              I am not looking for a great deal of acuracy. If i move the joystick 10% to the left and the linear actuator over shoots it by a couple of degrees it is ok, it does nto have to be precision in the control

                              This is how I thick it could work but really dont know
                              If the joy stick has a range of 0 to 5K on each axis and the nuetral postion being 2.5K and lets say I use pots for position on the linear actuators has the same range and nuetral postion. when the arduino sees any input other then 2.5k +- 200 it would send power to the actuator, probably thru relays to move it till it sees the same value as the input +- 200 (or what ever variation makes it the most drivable) and shuts off the power to the linear actuator till it sees a change in the input. I will probably need to have some sort of margin of error so it is drivable easily without it being twitchy.

                              As far as buying the off the shelf servo linear actuators with the control boxes, for $300 each, that would work fine if using a wireless remote. But I am hoping that either my linear actuators with the magnetic sensors or buying new linear actuators with pots on them for about $125 each can work just as well

                              The other issue I am trying to figure out is that I am converting the car form a mechanical speed controler to an electronic speed controler, The Electronic speed controler wants to see a resistance of 0 to 5k. I would like to have the forward / reverse axis of the joystick control the speed controler when moved forward and teh linear actuator for the brakes when moved backwards, I would think that this should be fairly easy to do withthe Arduino but not sure

                              I also need to have somesort of micro switchthat says the brakes are off all the way before aplling throttle, since the linear actuator will move slower then the joystick and Idont want to have the motor fighting the brakes

                              Once again thanks for all the great advice, questions and info
                              Doug


                              --- In SeattleRobotics@yahoogroups.com, Joe Justice <kiwikungfu@...> wrote:
                              >
                              > We have some linear actuators for programmatic control of parts of are car,
                              > see www.WIKISPEED.com for some more on that. Our shop is in Shoreline, WA,
                              > and we could show you how we've implemented them.
                              >
                              > Also, Tyler Folsom has an electric recumbent bicycle that is being converted
                              > to steer and brake by wire for full joystick control. Last I saw it the
                              > bicycle was very far along and he may be finished by now. He is in the
                              > Ravenna neighborhood of Seattle.
                              >
                              > Best, please post pictures and discoveries of your project as it moves
                              > along!
                              > -Joe Justice
                              > www.facebook.com/WIKISPEED
                              >


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