I can write a simple PID, but I am having trouble when I try to write one to handle more then one output. I would like to be able to have the two/four drive outputs have one group of gains, and also have separate gains for a turret, thrower wheels...

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Is this possible, and if anyone has done this can they show me how they did this.
EDIT: My goal is to have 4-6 output channels. 1-2 would have the same gains.