Loading ...
Sorry, an error occurred while loading the content.

Servo Sweep

Expand Messages
  • topazx2
    I have an arm on my robot that uses 4 GWS servos (non-modified), but when I test them with the setServo command, 0 - 100 doesn t service the entire sweep of
    Message 1 of 9 , Nov 1, 2010
    • 0 Attachment
      I have an arm on my robot that uses 4 GWS servos (non-modified), but when I test them with the setServo command, 0 - 100 doesn't service the entire sweep of the servo. I should be getting at least a 200 degree sweep, but the 0 - 100 limit only covers about 75 degrees.

      Is there anything that can be done to access a wider sweep?

      -Dan
    • ridgesoft
      Hi Dan, The servo class implementation for the IntelliBrain supports Futuba compatible servos which are controlled by a 1 to 2 millisecond positioning pulse
      Message 2 of 9 , Nov 1, 2010
      • 0 Attachment
        Hi Dan,

        The servo class implementation for the IntelliBrain supports Futuba compatible servos which are controlled by a 1 to 2 millisecond positioning pulse every 16 - 20 milliseconds. The pulse period is 18 ms on the IntelliBrain controller.

        There is no way to change this behavior.

        Regards,

        RidgeSoft Support

        --- In intellibrain@yahoogroups.com, "topazx2" <topazx2@...> wrote:
        >
        > I have an arm on my robot that uses 4 GWS servos (non-modified), but when I test them with the setServo command, 0 - 100 doesn't service the entire sweep of the servo. I should be getting at least a 200 degree sweep, but the 0 - 100 limit only covers about 75 degrees.
        >
        > Is there anything that can be done to access a wider sweep?
        >
        > -Dan
        >
      • topazx2
        I wonder if changing the servos potentiometer value by adding a resistor to the center leg would solve this? Hmmm, more on this later. -Dan
        Message 3 of 9 , Nov 1, 2010
        • 0 Attachment
          I wonder if changing the servos potentiometer value by adding a resistor to the center leg would solve this? Hmmm, more on this later.

          -Dan


          --- In intellibrain@yahoogroups.com, "ridgesoft" <rs1@...> wrote:
          >
          > Hi Dan,
          >
          > The servo class implementation for the IntelliBrain supports Futuba compatible servos which are controlled by a 1 to 2 millisecond positioning pulse every 16 - 20 milliseconds. The pulse period is 18 ms on the IntelliBrain controller.
          >
          > There is no way to change this behavior.
          >
          > Regards,
          >
          > RidgeSoft Support
          >
          > --- In intellibrain@yahoogroups.com, "topazx2" <topazx2@> wrote:
          > >
          > > I have an arm on my robot that uses 4 GWS servos (non-modified), but when I test them with the setServo command, 0 - 100 doesn't service the entire sweep of the servo. I should be getting at least a 200 degree sweep, but the 0 - 100 limit only covers about 75 degrees.
          > >
          > > Is there anything that can be done to access a wider sweep?
          > >
          > > -Dan
          > >
          >
        • David Suarez
          Ridgesoft, In reference to changing Servo class for wider sweep, Instead of changing Servo class, is there a way to extend Servo class ? I am knowledgable with
          Message 4 of 9 , Nov 2, 2010
          • 0 Attachment

            Ridgesoft,

                        In reference to changing Servo class for wider sweep, Instead of changing Servo class, is there a way to extend Servo class ?

             

                        I am knowledgable with JNI calls and I am fluent with C programming  so if I wanted to extend Servo class  so I can connect another controller via I2C with wider servo support.

             

                        Please provide tools needed to extend RoboJde.

             

                       

          • William J Rust
            I did this a long time ago so my memory isn t too great but ... I used a dio pin and pulsed it and then did a thread sleep to fill out the duty cycle. It s not
            Message 5 of 9 , Nov 2, 2010
            • 0 Attachment
              I did this a long time ago so my memory isn't too great but ...

              I used a dio pin and pulsed it and then did a thread sleep to fill out the duty cycle. It's not elegant but I remember that it more or less worked.

              wjr

              On 11/1/2010 11:50 PM, topazx2 wrote:
               

              I wonder if changing the servos potentiometer value by adding a resistor to the center leg would solve this? Hmmm, more on this later.

              -Dan

              --- In intellibrain@yahoogroups.com, "ridgesoft" <rs1@...> wrote:
              >
              > Hi Dan,
              >
              > The servo class implementation for the IntelliBrain supports Futuba compatible servos which are controlled by a 1 to 2 millisecond positioning pulse every 16 - 20 milliseconds. The pulse period is 18 ms on the IntelliBrain controller.
              >
              > There is no way to change this behavior.
              >
              > Regards,
              >
              > RidgeSoft Support
              >
              > --- In intellibrain@yahoogroups.com, "topazx2" <topazx2@> wrote:
              > >
              > > I have an arm on my robot that uses 4 GWS servos (non-modified), but when I test them with the setServo command, 0 - 100 doesn't service the entire sweep of the servo. I should be getting at least a 200 degree sweep, but the 0 - 100 limit only covers about 75 degrees.
              > >
              > > Is there anything that can be done to access a wider sweep?
              > >
              > > -Dan
              > >
              >


            • David Suarez
              Dan, I was the same boat a while ago, when I was trying to figure out why Parallax Standard servo sweep was only 0 through 160 degrees, Even if played around
              Message 6 of 9 , Nov 2, 2010
              • 0 Attachment

                Dan,

                            I was the same boat a while ago,  when I was trying to figure out why Parallax Standard servo sweep was only 0 through 160 degrees, 

                            Even if played around servo pot.,  you need to know how servo class translates number 0-100 positioning.  What is internal servo class doing with 0 through 100 ?  Unless Ridgesoft provides the code behind the scenes,  it will be a lot of trial an Error.

                            I am sure you can get hold of servo data specs, now you need the details of  Servo setPosition() method. Beyond API docs.  

                 

                            i

                 

                 

                 

              • topazx2
                Even with a futaba servo, the 0 to 100 sweep does not cover the full range of the servos potential. I ve tried GWS, Futaba, and Hitech. Oh well, I ll try to
                Message 7 of 9 , Nov 8, 2010
                • 0 Attachment
                  Even with a futaba servo, the 0 to 100 sweep does not cover the full range of the servos potential. I've tried GWS, Futaba, and Hitech.
                  Oh well, I'll try to make use of the limited sweep as best as possible.
                  -Dan

                  --- In intellibrain@yahoogroups.com, "ridgesoft" <rs1@...> wrote:
                  >
                  > Hi Dan,
                  >
                  > The servo class implementation for the IntelliBrain supports Futuba compatible servos which are controlled by a 1 to 2 millisecond positioning pulse every 16 - 20 milliseconds. The pulse period is 18 ms on the IntelliBrain controller.
                  >
                  > There is no way to change this behavior.
                  >
                  > Regards,
                  >
                  > RidgeSoft Support
                  >
                  > --- In intellibrain@yahoogroups.com, "topazx2" <topazx2@> wrote:
                  > >
                  > > I have an arm on my robot that uses 4 GWS servos (non-modified), but when I test them with the setServo command, 0 - 100 doesn't service the entire sweep of the servo. I should be getting at least a 200 degree sweep, but the 0 - 100 limit only covers about 75 degrees.
                  > >
                  > > Is there anything that can be done to access a wider sweep?
                  > >
                  > > -Dan
                  > >
                  >
                • topazx2
                  Yes, I agree. Unfortunately that detail is all compiled into the RoboJDE interpreter and is not available for the end user to modify.
                  Message 8 of 9 , Nov 8, 2010
                  • 0 Attachment
                    Yes, I agree. Unfortunately that detail is all compiled into the RoboJDE interpreter and is not available for the end user to modify.


                    --- In intellibrain@yahoogroups.com, "David Suarez" <dsuarez1@...> wrote:
                    >
                    > Dan,
                    >
                    > I was the same boat a while ago, when I was trying to figure
                    > out why Parallax Standard servo sweep was only 0 through 160 degrees,
                    >
                    > Even if played around servo pot., you need to know how servo
                    > class translates number 0-100 positioning. What is internal servo class
                    > doing with 0 through 100 ? Unless Ridgesoft provides the code behind the
                    > scenes, it will be a lot of trial an Error.
                    >
                    > I am sure you can get hold of servo data specs, now you need the
                    > details of Servo setPosition() method. Beyond API docs.
                    >
                    >
                    >
                    > i
                    >
                  • ridgesoft
                    Hi Dan, It looks like you can extend the servo pulse by setting a position greater than 100. The maximum that will work should be about 125 or slightly less.
                    Message 9 of 9 , Nov 10, 2010
                    • 0 Attachment
                      Hi Dan,

                      It looks like you can extend the servo pulse by setting a position
                      greater than 100. The maximum that will work should be about 125 or
                      slightly less. All 8 servos are multiplexed off of one pulse output
                      port. The pulse period is 18 ms, so the maximum pulse duration that can
                      be applied to any servo port is 2.25 ms (18/8 ms). The pulse duration
                      in milliseconds can be determined by follows:

                      duration = 1 + position / 100

                      So, for example, a position value of 120 would result in a pulse of 2.20
                      ms every 18 ms.

                      Regards,

                      RidgeSoft Support

                      --- In intellibrain@yahoogroups.com, "topazx2" <topazx2@...> wrote:
                      >
                      >
                      > Even with a futaba servo, the 0 to 100 sweep does not cover the full
                      range of the servos potential. I've tried GWS, Futaba, and Hitech.
                      > Oh well, I'll try to make use of the limited sweep as best as
                      possible.
                      > -Dan
                      >
                      > --- In intellibrain@yahoogroups.com, "ridgesoft" rs1@ wrote:
                      > >
                      > > Hi Dan,
                      > >
                      > > The servo class implementation for the IntelliBrain supports Futuba
                      compatible servos which are controlled by a 1 to 2 millisecond
                      positioning pulse every 16 - 20 milliseconds. The pulse period is 18 ms
                      on the IntelliBrain controller.
                      > >
                      > > There is no way to change this behavior.
                      > >
                      > > Regards,
                      > >
                      > > RidgeSoft Support
                      > >
                      > > --- In intellibrain@yahoogroups.com, "topazx2" <topazx2@> wrote:
                      > > >
                      > > > I have an arm on my robot that uses 4 GWS servos (non-modified),
                      but when I test them with the setServo command, 0 - 100 doesn't service
                      the entire sweep of the servo. I should be getting at least a 200 degree
                      sweep, but the 0 - 100 limit only covers about 75 degrees.
                      > > >
                      > > > Is there anything that can be done to access a wider sweep?
                      > > >
                      > > > -Dan
                      > > >
                      > >
                      >
                    Your message has been successfully submitted and would be delivered to recipients shortly.