When I started building my robotic actuator, I came across this cycloidal gearbox design and thought it was pretty elegant for such a small form factor. I began designing one for my 3D printer, but after growing slightly impatient waiting for the 3D printer to finish, I wondered if I could make one quicker than this. I remembered that there was a laser cutter I had access to at my university’s makerspace, and challenged myself to design this gearbox out of only acrylic parts.
It took… just a few attempts to get things to fit right, but I eventually did make a working gearbox out of only quickly laser cut acrylic parts from the scrap at the makerspace, plus a couple bearings, 5mm dowel pins, and some M3 bolts.
There are still plenty of issues with this design such as, tolerancing may be different on different laser cutters, it is loud at higher speeds, and there is a decent amount of backlash.
I have also since learned that my parts edges were not perpendicular to the faces because of a focusing issue on the laser cutter. I had thought that the parts were slanted at the sides because of a warp to the acrylic stock or laser cutter bed. The issue was that the focal point of the laser was set to the surface of the material creating a cone underneath, fixed by setting the focal point to the center of the material.
I will revisit this design. For the time being, the laser cut drive SolidWorks (2022) model is available on my lab’s webstore at https://store.ltr.dev
UPDATE: There are download links to the SolidWorks files in the project overview video: https://youtu.be/1xlKWT0U0n8