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Unread 01-03-2010, 16:24
AustinSchuh AustinSchuh is offline
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Re: WPI PIDController doesn't account for varying dT?

I believe that the reason that WPI left the dT part out is that since VxWorks is a real time OS, it's perfectly reasonable to assume that dT won't change very much.

A good exercise is to measure dT and see how much it actually varies.

If you were to submit a patch, you could scale the constants up and down internal to the loop by 50.0. KI should be 50 times larger, and KD should be 50 times smaller (provided I'm doing my math right, and assuming 50 Hz). That would preserve backwards compatibility.