Thread: PID vs Normal loops
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Unread 12-12-2007, 01:19
Salik Syed Salik Syed is offline
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Re: PID vs Normal loops
A cool idea would be to "learn" the (approximately) optimum PID constants over time...
You can simulate your robot arm pretty easily using a set of equations characterizing the mass distribution, and motor torques.

Next create several test goal and end states within reachable bounds of the system (a state would be angle + angular momentum for each arm segment)

Do a search through the set of all PID combinations to find the best one.To test optimality, simply use the PID constants and run them on your simulation, use a metric for how good the performance is (power usage, time to reach goal etc..) . It shouldn't take more than a few minutes on a modern computer. (of course you don't want to try every possible combination since it's infinte, but discretize the selection based on how large or small the term is probably going to end up being)

If you need help programming this feel free to post, it isn't half as complicated as it seems. In fact maybe I will make something that does this over winter break lol.
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Last edited by Salik Syed : 12-12-2007 at 01:29.