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Unread 05-07-2016, 16:50
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Re: Good way to bring shooter to exact speed?

I'd go for a PID. You'll need to convert the encoder count to a 0-1 range of speeds, but otherwise, if it's like it was back in the old days (2011), it's pretty easy to set up.

As for tuning said PID, there are various ways (google it, as I don't have my controls textbook handy). Whichever tuning technique you use, you'll want to get it so it has a quick response without breaking anything, blowing anything, or oscillating. I'd avoid over-tuning (getting it really, really spot on) as you're liable to become marginally stable (which puts you one bit of drift away from instability).

Yeah there is probably an easier FRC-specific way to do this, but this (minus the PID code) is what they do in industry and will likely produce the best results possible with your hardware. As many of us know, controls can be temperamental to tune, but when you get it right, it will deliver.
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