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Unread 14-03-2016, 20:20
Oblarg Oblarg is online now
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AKA: Eli Barnett
FRC #0449 (The Blair Robot Project)
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Re: Velocity PID control and setpoint ramping

Quote:
Originally Posted by Alan Anderson View Post
Consider what would happen if you added feedforward and took the output of the FPID directly to control the motor rather than integrating it.
This would certainly be another way of doing velocity control. I don't think I can guess exactly what the differences in performances would be without having an actual robot to test it on - naively, I suspect that doing this could yield faster response times than integrating the output (since the F term provides an immediate approximation of any desired output, while we have to wait for the integrated output to reach it) but we're not really worried about response lag.

It's worth noting that we're not seeing any problems with oscillations or overshoot, we're more worried about the taxing effect on the drive components from the (correct) behavior of the motors fighting the robot's forward momentum to come to a stop quickly.
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Member, FRC Team 449: 2007-2010
Drive Mechanics Lead, FRC Team 449: 2009-2010
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Last edited by Oblarg : 14-03-2016 at 20:23.