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Unread 22-05-2016, 01:53
MichaelBick MichaelBick is offline
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Re: NavX MXP Continuous Angle to Calculate Derivative

Quote:
Originally Posted by notmattlythgoe View Post
One thing we've been trying is using a closed loop to control the rate at which the robot turns and then use a P controller to tell the first controller how fast to turn based on how far away from our target angle we are.
We did something similar this year. We ended up running a rotational velocity P controller with feedforward as the baseline of our turn controller. We summed the output without the feedforward, and limited to +-20% voltage to help prevent windup. A PD controller on turning angle was the input to the velocity controller.

There was definitely a noticeable improvement on the conventional PID controller. One problem we were facing without the velocity controller was that our turns were highly dependent on momentum. We really would have liked to run the velocity loop underneath our teleop driving code too, but integral windup caused a lot of unpredictable behavior over long periods of time.
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Last edited by MichaelBick : 22-05-2016 at 01:57.
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