Split Ring Gearbox Generator w/ Bearings & Encoder

Description
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Split Ring gearboxes are known for being able to get very large gear
reduction with very few stages. The details for the design captured
here were mostly provided by David Hartkop. See:
https://github.com/IdeaPropulsionSystems/CoolEpicyclicGearing
https://www.youtube.com/watch?v=-VtbSvVxaFA
I really liked this design because it kept the planet teeth
aligned with one another making them easier to 3D print as well
as allowing for an output sun gear to help prevent the planet
gears from twisting under load. While I can get very high
reduction very easily with this design, I tended to need much
less reduction in practice but instead used it as the final output
stage for various arms which need to support more torque. The
secret to that was to print them big and use lots of planets.
Maintaining the input/output modulus greater than 1 is likely to be
helpful as well.

I wanted to build this gearbox for a robotics application but I
needed bearings to support