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Unread 27-10-2014, 11:26
AustinSchuh AustinSchuh is offline
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Re: Jaguars and FAST PID Looptimes

Quote:
Originally Posted by Joe Johnson View Post
BUT... speed has a dark side. Speed is hard to control, especially at 50hz update rates typically used in FIRST control loops (I want to have 90 degree step change in steering angle in under 60ms -- probably too fast to have a 20ms loop time).
20 ms is the old Victor update rate. You can hit 5 ms (might need to tweak the WPILib constants, can't remember, but the hardware can do it) with the Talon SR. That gives you 12 cycles to settle, which might be enough.

How did you come up with 90 degrees in 60 ms?