[Kevin Selavko]

If you have your omni wheels in a configuration like this,
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or are using mecanum wheels I would probably suggest using a game pad because it already has two joysticks on it so there would be less wires and you have up/down/left/right buttons. You definitely need to have dead zones. I would also suggest having a buttons to make it go strait in any direction so that if you push the up button it will have all the motors go forward at a selected speed, down button all go reverse at one speed, left button two go forward and two go reverse at the same speed, and if the right button is pressed do the reverse.