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Unread 28-10-2012, 01:56
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Alan Anderson Alan Anderson is offline
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Re: Robot "kicks out" when it goes right

Quote:
Originally Posted by Ether View Post
Could someone explain why this would cause the drivetrain would work fine in the forward, and reverse, and rotate left directions, but not in the rotate right direction?
Assume four motors, two on each side. Further assume that the wiring is such that one side's motors run "forward" and the other side's motors run "reverse" for forward travel of the robot.

The DS can "sneak" some power from the PWM signals coming from the cRIO. When the robot is being commanded neutral, it's getting four 1.5ms pulses every so often, and that's enough to make it work. When it's being commanded either forward or reverse, two of the signals get shorter, but two get longer, and it balances out. When it's being commanded to turn left, all four signals get longer. But when it's being commanded to turn right, all four signals get shorter, the DS gets starved for power, and things stop working.
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