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Unread 25-12-2012, 01:48
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z_beeblebrox z_beeblebrox is offline
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Re: Motion Profiling

I'm on my third rewrite of this sort of code for Vex and I've learned that position PID with no acceleration limiting makes robots do wheelies and that speed PID is very hard to tune. My third iteration uses position PID with acceleration limiting and seems to be working very well. I'm curious why you would want to use motion profiling rather than just PID, as a well designed and tuned PID controller with acceleration limiting approximates the results of a trapezoidal speed curve, as can be seen in the data from running my program on a Vex robot:

(Column C being position in inches and Column D being speed in inches / second)
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Last edited by z_beeblebrox : 25-12-2012 at 01:51.