I started the design of the internal gear and the planetary gears.

Since we have an idea of how big we want the device to be (approximately 90 mm in diameter), I am starting with that constraint. Additionally, the planet gears cannot be too big since we need space for components. I am aiming for a 15-mm diameter for the planet gears.

Other parameters that I am considering:

Module = 1

Preasure angle = 20

Ring gear number of teeth = 80

Planet Gears number of teeth = 15

Backlash = 0.1 (I am adding this because the gears will be 3D printed.)

Gear thickness: 4 mm (as per the width of the bearing that we ordered).

Next challenge: define the joints in Fusion 360 assembly so the planet gears and ring gear work without a sun gear or planet gear holder.