This joystick was designed to replace the failing resisitve joystick of a PI Micos SMC Corvus eco three-axis stepper motor controller.
The design has a primary XYZ joystick (Apem HF46S10) where the Z axis is the rotatable shaft and a secondary stick (Apem BF150A01BK0500) only for the Z axis.
Which Z axis is applied at the analog output can be controlled with a switch while all four signals are available at the analog inputs of the integrated Teensy 3.x microcontroller board.