[russell]

Would it be easier to use the y axis of the joystick, and the joystick wheel to control the location of the tip of the arm? Like make the height of the arm equal to the value from the wheel, then make the horizontal distance to the tip of the arm be equal to the y axis of the joystick. Once you knew that you would know the lengths of all three sides of a triangle, which would allow you to use trig to find the angles at the corners, and set your arm to those angles. Something like that. You could also use the X axis to do the same thing as the wheel, but that would be weird to operate.