Azimuth over Elevation Differential Pan-Tilt

This was a prototype for a pan-tilt. My aim was to have all the motors fixed so as to not need any slip rings. Additionally I wanted to leave a hollow central shaft to allow any cables to run up the centre.

It runs from a pair of cheap 28BYJ-48 geared steppers which can be picked up very cheaply from banggood or other China exporter.

It works, but needs lots of work to be useful. After building this I realized that I really needed a conventional Elevation-over-Azimuth pan tilt so gave up on this design. I have since got a differential drive version of the El-over-Az working, but the files need some work before it can be shared.

Gears were pulled from here http://www.thingiverse.com/thing:3575 . There is now a spiral bevel gear available that works more smoothly here. http://www.thingiverse.com/thing:1604369 (but sometimes comes out with non-manifold STL's)