Quote:
Originally Posted by Oblarg
So, here's a graph of our flywheel velocity error (units in RPS) versus time during a shooting test. The negative spikes are slowdown while the flywheel is in contact with the ball. The velocity setpoint was 50 RPS.
As we can see, consistent with the above discussion, there is steady-state error, but it is very small.
We are wondering if teams bother to introduce any integral gain to eliminate the steady-state error, and if this performance is consistent with what other people have seen using similar methods. |
We didn't use integral gain, but we did use some derivative gain to lessen the initial overshoot, and a 36V/s rate limit to smooth things out a bit:
https://github.com/Team254/FRC-2016-...ants.java#L152
(Talons were in coast mode as well)
We allowed firing whenever our flywheel was within 100rpm (1.67rps) of our setpoint because we found it made no practical difference to our shot trajectory. In practice, most shots we took were within 20rpm of our setpoint. If you are within .1rps (6rpm) steady-state, I'd say you're already in good shape.