[SuperS_5]

If you mean the throttle axis, then yes this is possible to use this in the robot. Your question is a bit confusing though. Did you want to throttle your shooting motor, or the robot drive. I am not sure why you would use the joystick x/y axes for the shooter.

In terms of solutions; you only have to multiple the throttle axis with the desired axis or numerics chosen by a button press. I believe the output of the throttle is between 0 and 1, and therefore directly applicable as a percentage of range. (decimal form)