Robot Grabber

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kieran-pierce
Posts: 10
Joined: 02 Nov 2012, 22:14

Robot Grabber

Post by kieran-pierce »

Hi all,

I need some advice on the best way to code a grabber. What i have now is this

Code: Select all

void RotateMotorRURD(byte output, char pwr, long angle)
    {
      long l1, l2, l3;
      char power = sign(angle);
      angle = abs(angle);
      power *= pwr;

      l1 = angle*0.20;
      l2 = angle*0.60;
      l3 = angle-(l1+l2);
      // we want to rotate a total of <angle> degrees
      // we'll rampup from 0 power to specified power through 20% of the angle
      // then run at the specified power for 70% of the angle
      SetOutput(output, OutputModeField, OUT_MODE_MOTORON|OUT_MODE_BRAKE,
                        TachoLimitField, l1,
                        PowerField, power,
                        RegModeField, OUT_REGMODE_IDLE,
                        RunStateField, OUT_RUNSTATE_RAMPUP,
                        UpdateFlagsField, UF_UPDATE_MODE|UF_UPDATE_SPEED|UF_UPDATE_TACHO_LIMIT);
                        
      Yield(); // give firmware a chance to process this request to update motor state
      
      // monitor runstate
      while(MotorRunState(output) <> OUT_RUNSTATE_IDLE)
        Yield();
      // as soon as it goes idle put the motor into the running state
      SetOutput(output, OutputModeField, OUT_MODE_MOTORON|OUT_MODE_BRAKE,
                        TachoLimitField, l2,
                        PowerField, power,
                        RegModeField, OUT_REGMODE_IDLE,
                        RunStateField, OUT_RUNSTATE_RUNNING,
                        UpdateFlagsField, UF_UPDATE_MODE|UF_UPDATE_SPEED|UF_UPDATE_TACHO_LIMIT);
      Yield(); // give firmware a chance to process this request to update motor state
      // monitor runstate
      while(MotorRunState(output) <> OUT_RUNSTATE_IDLE)
        Yield();
      // as soon as the runstate goes idle we rampdown to zero power
      SetOutput(output, OutputModeField, OUT_MODE_MOTORON|OUT_MODE_BRAKE,
                        TachoLimitField, l3,
                        PowerField, 0,
                        RegModeField, OUT_REGMODE_IDLE,
                        RunStateField, OUT_RUNSTATE_RAMPDOWN,
                        UpdateFlagsField, UF_UPDATE_MODE|UF_UPDATE_SPEED|UF_UPDATE_TACHO_LIMIT);
      Yield(); // give firmware a chance to process this request to update motor state
      
      while(MotorRunState(output) <> OUT_RUNSTATE_IDLE)
      Yield();

      SetOutput(output, OutputModeField, OUT_MODE_MOTORON+OUT_MODE_BRAKE+OUT_MODE_REGULATED,
                        TachoLimitField, 0,
                        PowerField, 0,
                        RegModeField, OUT_REGMODE_SPEED,
                        RunStateField, OUT_RUNSTATE_RUNNING,
                        UpdateFlagsField, UF_UPDATE_MODE|UF_UPDATE_SPEED|UF_UPDATE_TACHO_LIMIT);
      Yield(); // give firmware a chance to process this request to update motor state
    }





task main()
{
 InitGrab();
 
 RotateMotorRURD(OUT_B, 50, 30);
 Wait(10000);
 Off(OUT_B);
this works fine and will break the grab when its in the right spot but the amount of back lash in the link means that it can still release an object, so I was thinking I could keep the power on to close the grab even though it is closed and then release it only when I need to open the grab what do you think
kieran-pierce
Posts: 10
Joined: 02 Nov 2012, 22:14

Re: Robot Grabber

Post by kieran-pierce »

I went for keeping the power on and it seems to work quite well
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