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Unread 18-02-2006, 14:47
KenWittlief KenWittlief is offline
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Re: How Can I aim at the Vision Target Faster but without overshooting?

you have discovered the world of PID control loops.

When your system overshoots that means the gain on your Proportional (the P part) is too high

you can fix this by lowering the gain, or adding the D part (differential) to the feedback algorithm.

If you think of it in terms of distance, velocity and acceleration (of your robot to point towards the target) then the P is like distance (how far off are we from where we want to be)

the D is like velocity (how fast are we moving towards the place we want to be)

and the I is something you use to make fine adjustments to the P (how far off we are times how long we have been 'off').

This is a whole semister in college - a very deep subject. To be honest the best approach is to keep turning your gain down until you stop overshooting, or you overshoot just a little and then center on one 'bounce'.

Adding the I and D to the loop is more complex, and it will only make your response time slightly better than the slight-overshoot response time.