We have done FRC Characterization on one of our chassis, and we have gotten acceptable position PID values. We ran using the position values and the robot went the suggested distance. But for velocity PID we got 0.341 as the P and 0 for I. These values were tested for going at 10 inches per second and the robot oscillated and never reached the desired velocity. The P value taken from FRC Characterization seems too high, and so is there a way to get a lower value by different tests or something?
You have likely made a unit error somewhere; in order to help you I’ll need more information about your setup.
I have attached our Data Analyzer above.
So, your kV suggests that your units are weird - 12 / kV gives an estimate of your max speed in your units of analysis, which in your case is ~65 units/second. If your units are inches, this is very slow (it’s about 5.3 feet per second, which only makes sense for the low gear of a shifting drive).
Past that, the Talon (2020-) preset for the gain settings shouldn’t be used because CTRE has not yet implemented their units update for the Talon library. Moreover, if your units are inches, a max acceptable velocity error of 0.2 is tiny (think about how small 0.2 inches per second is).
Remember, as well, that a P loop for a velocity controller will not ever work acceptably without feedforward; if you were getting oscillations without reaching the setpoint, you were probably omitting the feedforward.
If I had only seen this 2 hour old post 4 hours ago.
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