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Unread 03-08-2016, 02:18 PM
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Jared Russell Jared Russell is offline
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FRC #0254 (The Cheesy Poofs), FRC #0341 (Miss Daisy)
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Re: Heading PID tips

Quote:
Originally Posted by cjl2625 View Post
Wouldn't this cause oscillations, if the output switches between positive and negative of this magnitude?

As a related idea that I had, I wonder if it would make sense to find some magnitude where the robot almost turns (but is still stopped) and add it to the PID output. Maybe it would simulate low friction or something.
In practice you are typically moving so slowly at this minimum output that the oscillation shouldn't be a problem (you probably have a small deadband around the setpoint at which point you say "good enough" and cut power).

Adding a minimum term to the output is also a totally valid approach that accomplishes the same thing and only differs in the details.