Need assistance with Sysid, values are changing

Hello Chief Delphi, I am posting here on behalf of team 614 robotics, the nighthawks. We are experiencing problems with Sysid. We ran all the tests and noticed dragging occurring during the test in which the same voltage was applied to both sides of the drive train. Essentially, one side was transferring more voltage into motion, while the other was dragging behind. In our troubleshooting, we found that, as shown in the images attached (top and bottom are the same side of drivetrain), when clicking off and on one of the sides, the values displayed changed. We clicked left side once, got one value, and clicked off. As we clicked back on, the values changed. Any help?

This probably means your drive sides are not actually mechanically equivalent. You can either compensate for it in code by using the different gains, or (recommended) try to diagnose the mechanical issue causing the difference.

Edit: given the factor of two-ish difference in Ka, have you considered that one of your motors might not have been running?

To clarify, the values for a given side change.
That is, for example, going from “combined” to “left” gives one set of values, and then clicking on “left” on the dropdown again shows a different set, even though those values should not change.
Afaik the screenshots above are for only one of the sides.

Ah, hrm. I’d disregard the second set of values entirely in that case, and file a github issue; this is probably a bug in the subsetting logic (which should be idempotent…).

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