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Unread 28-02-2012, 17:59
Tom Bottiglieri Tom Bottiglieri is offline
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Re: Speed PID Function

Quote:
Originally Posted by vamfun View Post
note-velocity-pid-loop


This note on Velocity PID controller addresses your questions on how to obtain the open loop motor time constant tau_m. If testing is available always use that source since there is really no such thing as a spec motor. However, I use spec data to precompute gains since the gains will be adjusted anyway when we optimize the loop gains during integration testing. Often , very little adjustment is needed.

The note also comments on various ways to implement a PID loop in software.
You note that tau_d = tau_m/r. How does one find R? Do we just choose this? If so, what is a reasonable choice?

Last edited by Tom Bottiglieri : 28-02-2012 at 18:03.