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first95 / FRC2016

The codebase for our 2016 robot
GNU General Public License v2.0
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Knowledge About PIDF #12

Closed setupminimal closed 8 years ago

setupminimal commented 8 years ago

First: The F term accounts for 95% of the adjustment. Set the F term about as though you were in open loop mode.

The other three terms deal with eccentricities of the motor, etc.

Also: Voltage output varies with battery voltage, so if you correct for the battery voltage, you get better performance.

setupminimal commented 8 years ago

Done for now.

jwalthour commented 8 years ago

My phrasing of @setupminimal 's first comment: Roughly speaking, if Vout is the effective voltage sent to the motor, s is the setpoint value, and e is the "error" between the setpoint and the current speed: Vout=Fs + P * e + I * (integral of e with respect to time) + D \ (de/dt) Thus, F does not refer to the previous iteration of the control loop, but rather refers to a shortcut around the normal control loop.