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Unread 17-11-2016, 16:36
Oblarg Oblarg is offline
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AKA: Eli Barnett
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Re: Velocity PID(F) Best Practices - To Integrate, or Not To Integrate?

Quote:
Originally Posted by Jared Russell View Post
In a velocity controller, inertia has a linear effect. If you change the sign of the control output, you expect your system to begin accelerating in the opposite direction immediately (modulo small but inevitable delays in your system). This means you can get away with really high gains without experiencing stability problems. Ex. a bang-bang controller essentially has an infinite proportional gain yet remains stable for many systems.
So, basically, if you're using feedforward, you can make the 'p' gain in a non-integrated velocity controller big enough that the fact that it can't theoretically push the velocity all the way to the setpoint (even as t->infinity) is essentially moot, without running into stability issues?
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Member, FRC Team 449: 2007-2010
Drive Mechanics Lead, FRC Team 449: 2009-2010
Alumnus/Technical Mentor, FRC Team 449: 2010-Present
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