Thread: PID Loops
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Unread 13-03-2011, 15:44
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Re: PID Loops

Quote:
Originally Posted by archaopteryx View Post
I'm not a mathematician, but couldn't , where K is a constant, simply do without K? If pedal and error have a direct correlation, why can't you just say that pedal = error and leave it at that?

If you are trying to move your car at 50 mph and currently, the error from this target is +10 mph, does it make sense to push the pedal down at 10 mph? A correlation does not mean an equivalent 1 to 1 relation. Another example is if you are trying to drive your robot 5 feet forward and the current error is 4 inches. Does it make sense to tell the motors to drive at 4 inches? Built into the k value is unit conversion among other things.

Last edited by Chris27 : 13-03-2011 at 15:48.