> QUESTION: The circuit will be PIC enabled.  Does anybody have
> recommendations on the best way to compensate for the difference
> in rotation?  I don't want the robot forever moving in circles.
>
> John Mullan

How about identical sensors on each shaft and then check for the
arrival of the pulses from each. If one starts to lead, then ease off
its drive until the two are in synch. Finer resolution, more pulses
per rev, like a simple slotted disk and opto, would give less noticeable
adjustment

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