A project log for Hi torque 3d printed cheap robot actuator

Cheap 3d printed hi torque robot actuator with electronics

pavel-gPavel G. 05/07/2020 at 23:580 Comments


I decided to develop gearbox with ratio from 1:25 to 1:35 to archive 180 degrees per second with full torque (i hope).

Small backlash is acceptable (at least for robot leg actuator)

All designs will be created in Openscad.


I  had a few experiments in the past: So my favorite designs are: 

1) Spur Pinion  double gears organized in 3 gears per stage (each stage is a 3 spur-pinion gears at triangle corners) with ring gear as output: Openscad drawings and visualization will be uploaded soon.

This type of gearbox have 1:33 ratio (can vary, but not limited at max)

2) Cycloidal - i experimented in past, I got 1:25 ratio (strong limit for 70x70 cm footprint), but my past experiments had some Issues (mostly because of missing bearing at critical places)

Best ideas for Cycloidal you can see here:

Gearbox exploded view concept

Key features: 

Gearbox disassembly video

Assembled gearbox

Actuator test without absolute encoder

Gearbox test with absolute encoder