paper: Shooter Wheel Speed Control

[Ether]

When reading the values, we saw an average of 15 RPM difference from our set point for the RPM. If we had more time to dedicate to JUST tuning that, I feel we could have gotten a little bit more accuracy on that.

You didn't mention, but I assume you had the Jag set for coast mode, not brake, correct?

If you get a chance, try getting rid of the voltage ramp*, and increase the update rate to 20ms instead of 50ms.

We believe that having it go directly to the Jaguar, NOT the cRIO's FPGA, allowed it to be read faster.

I would think that reading the FPGA would be much faster than talking to the Jag via CAN bus. Does anyone have numbers for this?



*unless you need the voltage ramp to keep the Jag from shutting down at spinup. If so, try turning off the Jag's voltage ramp and put a ramp in the cRIO instead, and make it active only in the increasing direction, and only for speeds below the necessary spinup speed.