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Unread 18-02-2015, 23:35
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Jared Russell Jared Russell is offline
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Re: Keeping two motors in sync

Quote:
Originally Posted by Ether View Post
Could you elaborate on what you mean here by "integrating encoder values over time"? Could it be as simple as just using encoder counts instead of rate?
Yeah. The process variable for the steering controller in a differentially steered vehicle is heading, which is just the difference in encoder counts times a constant (to do a unit conversion). The constant is theoretically the inverse of the radius of the wheelbase; in practice you can tune it empirically to incorporate slip (if desired).

In the generalized motor synchronization case, using (left_distance - right_distance) would be fine.

Using a trajectory generator to make nice smooth, non-saturated position setpoint profiles is a great way to help solve the saturation/windup problem.
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