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Unread 21-03-2012, 15:24
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Re: Alternative to PID speed control

Quote:
Originally Posted by martin417 View Post
We used a very simple closed loop control that worked flawlessly. We had a jag on CAN bus with an encoder attached to the jag. We used voltage control with a voltage ramp of ~115 V/S. We queried the jag for speed, and if the speed was less than the set speed, we set max voltage. If the speed was greater than or equal to set speed, we set zero voltage. The inertia of the system kept the shooter speed within ~15 RPM of set speed at all times, and when we shot, the voltage immediately went to full for rapid spin-up.

the simplest solution that works is usually best.
A couple of questions:
1. How often were you asking the Jag for the speed?
2. How quickly were you running the control loop?
3. Were you able to compensate for the load that the ball puts on the motors quickly enough as to keep them at the correct speed?
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