The joint actuator — a motor, a reducer, an encoder and a driver in one package — is the single most important component
in a humanoid robot. This is a personal, liquid-glass guide to the makers building them and the specs that separate them.
How this was made
There's no single catalog for this corner of the industry, so the lineups and specs here were researched
and cross-checked from manufacturers' official datasheets and stores by an automated research pass built with
Claude. Specs move fast and some makers publish
little — anything that couldn't be verified is left blank rather than guessed, and prices are indicative.
Built by Claude, easy to update & open to all
Built by Claude for Jerry Cheng. It reads a
single actuators_data.json, so the guide can be refreshed any time. Corrections and additions are welcome —
especially datasheet numbers and new models.