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Unread 12-02-2011, 17:31
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AKA: John Maguire
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Join Date: Jan 2011
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LabVIEW Jaguar issues

My team has been working on getting mechanum drive setup on our robot for quite some time now, and we're have a very bizarre issue. We have the code we think working properly, using the provided holonomic drive library, and it's almost functional, the following actions work correctly:
  • Drive forward
  • Drive backward
  • Drive left
  • Drive right
  • Rotate right

However, upon trying to rotate left we found a very strange issue: It will rotate if the joystick is tilted until approximately "-.35" on the axis, and then will lose servo connection (yellow blinking lights.) Again, we can rotate right completely fine, up to a "1" on the axis. This is of course an issue because it means we can't rotate left very quickly (also the -.35 was around -.5 that it stopped working earlier, so I fear it's quickly getting lower.)

We decided that maybe something was wrong with our Jaguars and tried the LabVIEW "Motor Control Example." We found that both of our right motors was able to spin from "-1" to "1" using the slider, but our left motors had issues in the negatives (all the positives were fine.) When we got to around "-.7" on one of them, it starts jerking (moving at a decent speed, jerk to a stop, starting moving again). At "-.8" it was jerking harder and longer, and at "-.9" it lost any kind of movement. With the second left motor we had the same thing except it was jerking at "-.8" and "-.9" and lost any movement at "-1".

We thought maybe the calibration was off, but were unable to calibrate the Jaguars because first we had issues getting it to the red and green blinking mode. When we finally did, we used the "Motor Control Example" to send a "1", "-1", and then a "0" to the PWM, but it kept blinking green and red.

Any help would be appreciated.

Thanks,
John
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