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Unread 23-02-2012, 16:53
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Re: Speed PID Function

Quote:
Originally Posted by Ether View Post
Can you address this in a bit more detail?

Are there some fairly simple tests that a team could do to obtain this number?

Or do you recommend calculating, and if so it might be helpful to do a blog entry on that or post some example calculations here.


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.