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Unread 06-03-2012, 09:17
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JamesCH95 JamesCH95 is offline
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AKA: JCH
FRC #0095 (The Grasshoppers)
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Re: Problems with tuning shooters using AM basketballs on Practice Field?

Quote:
Originally Posted by squirrel View Post
I'm thinking that this is a good solution to part of our problem. I wonder what the odds of us being able to implement new code on Thursday (AZ regional) are?
Very high I'd bet. Our student programmed disabled the PID loop and added the voltage control in 10 minutes. I'm no expert, but it seemed very simple.

Quote:
Originally Posted by wireties View Post
So a gain that made it stable with no load did not compensate for the change in load when compressing a ball? Then raising the gain to help made it oscillate under no load? We might have the same problem... what motors do you use?

For teams incorporating a compensation factor - was the factor a simple constant or a constant multiplied by V or maybe V squared?

TIA
I believe that's what was happening to us. We're using two RS550s for our shooter. PIDs might work better for other teams with higher-inertia shooters. Our shooter consists of five 4" long rollers made from 0.065" walled aluminum tube, there is hardly any mass/inertia there. We couldn't even get a stable no-load PID loop, it was causing some seriously scary motor arcing.
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Theory is a nice place, I'd like to go there one day, I hear everything works there.

Maturity is knowing you were an idiot, common sense is trying to not be an idiot, wisdom is knowing that you will still be an idiot.
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