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Unread 06-11-2005, 21:21
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Pat Fairbank Pat Fairbank is offline
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FRC #0254 (The Cheesy Poofs)
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Re: EDU Mini Controller & 2005 Nav Code

Quote:
Originally Posted by jaustin
I'm wondering if there is some inherant issue with either the EDU mini controller or the motors?
I still own and use one of the old Robovation kits, and I've observed that there is in fact a HUGE difference in the forward and reverse speeds of the motors. If this is what is causing the problem in your case, when you run the robot backwards the right motors should now rotate faster than the left motors. I think I've had to cut back on the speed of one motor by as much as one half to compensate.

The PID loop in the navigation code probably isn't designed in a way that would allow it to compensate for this much a speed difference (between the expected and actual speeds for forward and reverse), so your best bet is to follow Mark's procedure and slow down the motors for the appropriate direction of rotation in the code, after having run the PID loop.
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