This is a 40" tall horziontal and vertical axis rotator for antenna testing and pre-FCC certification testing.  The entire mechanism (above the stepper motor) including ball bearings and drive components, was constructed with non-metalic materials.  BTO Corporation designed and built the mechanism, the stepper motor controllers boards, and controller packing.  We wrote the embedded stepper firmware and the communication, control, and diagnostic software.

See StepperII documentation