I've been working on a DIY camera gimbal that started as a mechanical design project and has evolved into a computer-controlled astronomical tracking system.

The goal was to build something that could be operated manually with an Xbox controller, automatically point a camera toward celestial objects, and track them for astrophotography.

The system is now functional, and I've recently had successful tests tracking Jupiter and Sirius.

Mechanical design

The gimbal is largely 3D-printed, with aluminum 2040 V-slot extrusions providing the structural rails.

It has three motorized axes:

Yaw: NEMA 17 stepper motor driving a 20-tooth pinion and 180-tooth gear, providing approximately 9:1 ratio. The yaw axis presented an interesting bearing challenge. I ended up using a vertical steel shaft resting on a glass (or steel) marble seated in a pocket. The marble carries the axial load, while two additional bearings support the shaft against radial loads. The entire pitch assembly is mounted to this shaft.…