"Real time" move with tilt, pan, and roll moving through 360 degrees.
The steppers are 0.9 degree step with 100:1 gearboxes driving a final pulley ratio of 6:1 giving an overall ratio of 600:1.
Backlash on pan gearbox is >15 arc minutes, tilt and roll >10 arc minutes divided by the final 6:1 ratio to give a smooth motion at the "tipping" points.
The move was made with the stepper controllers set to 1/2 step mode giving a speed of approximately 360 degrees / minute.
Next is to motorise the x 16 roller trolley that runs on 2 off - 4ins square x 6ft 6ins carbon fibre tubes and carry out repeatability tests.