In a hypocycloid (or simply cycloid) speed reducer, a flower-shaped gear called cycloid disk moves around a stationary ring of round pins in a cycloidal motion, driven by an eccentric bearing or cam connected to the input shaft. Radial holes on the face of the cycloid disk in turn drive the pins of the output shaft.
The cycloid disk is the most important piece of the hypocycloid drive, and also the most complex. However, with the help of the online calculator we have developed, the profile of a cycloid disk can be modeled literally in seconds. This tutorial demonstrates how to do that plus how to design the other less difficult parts of the hypocycloid drive, and animate them too.