2015 FRC Mechanum Sample Code Problems and Fixes

Mechanum Sample for 2015 FRC seems to be faulty.

We have noticed (and fixed) a few problems in the sample Holonomic Mechanum Cartesian code:

  1. The joystick inputs have Rotation, X and Y messed up. We had to fine-tooth-comb which should be hooked to what, but once we found the right VI, it was not difficult.

  2. The motor comments that specify which motor gets which port has an error which prevents lateral X motion. We switched the wires between port/motor 1 and 3 and now it works fine.

Not sure how this slipped through, I hope this helps other teams (particularly newbies) to get their mechanums working.


Could a LabVIEW guru please comment on the above?

It’s not exactly going viral, but it is getting some airplay.

I looked at the code and see nothing that looks incorrect.

The joystick axis selection was changed to be array based, and I don’t have a true joystick to test with at the moment, but I don’t think that it looks wrong.

The labels for the motors look consistent, and of course have arbitrary PWM channels selected. I’ll respond to the algorithm question in the other thread.

Greg McKaskle

There is absolutely nothing wrong with the default mecanum LabVIEW code.

The problem is that there are several ways to get the wiring to the motors not to match the inputs to the Open 4 Motor function, and they all can give a casual observer the impression that it’s the rest of the programming that’s broken.