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Unread 07-02-2014, 15:51
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More Torque!
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Re: Arm Position Control

Quote:
Originally Posted by Bpk9p4 View Post
-In the context of an arm, velocity PID is useless. It would not provide the desired response at all.

Maybe i read his question wrong but if you are wanting to move the arms from 0 deg to 180 deg and have your controller take into account the increased torque a velocity PID controller would be perfect for this.

This would allow the arms to move at a constant angular rate regardless of the torque needed.

However this would not allow the arm to stop right at 0 and 180 deg. To do this you would need to transition from the velocity control to a position control when you got close to your desired position.
Or you could rely on the derivative control to slow it down properly.

Stacking and switching PID controls is usually a lot more work than it's worth.



I agree Joe, the need for any gain scheduling or other controls is dependent on the arm. Some arms need adjustment, some do not. I have worked with both.
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