I have been looking at this, as I have incorporated the size change for the extra precision in the distance between wheels box.
One issue I notice, the input box strips trailing zeros and does not enforce two digit precision. (i.e. If you enter a number with a trailing zero in either of the two boxes, the trailing zero disappears. Excessive input precision causes the number to be chopped off on either side.)
I did a bit of looking at the wxPython classes/methods as well as the “param” class and its methods, and I believe that constraining and formatting the inputs there can be done. But it would be a BEAST (IMHO, based on my limited skill), requiring extensive modifications to the control panel software. (Your own evaluation would be valuable)
If, (and that’s a big if), I get the time to mess with the control panel In The Big Way, I would be looking at a total re-write as a tabbed interface that will allow tuning of a number of different parameters.
That’s in the distant future. I still want to figure out why the Pi-4 chews up the firmware and I have not figured out how the bit-clock constants are calculated - so I cannot confirm or deny that there might be issue with that, (These need to be calculated based on processor speed, and that can vary, so there’s a potential problem right there.)
I also want to continue work on the joystick controlled robot, so major rework to the control panel will have to wait in line unless an old code-hound like yourself wants to chew on it. (Yea, right!)