What a humanoid is made of

26-08-31

A schematic humanoid drawn as a chain of geared joints, with six suppliers called out on the joints they sell into: Ambarella at the head, Harmonic Drive at the shoulder, Yaskawa at the elbow, Schaeffler at the wrist, Nabtesco at the hip and Nidec at the knee. A dashed band beneath the figure reads: material, sintered NdFeB, about 1.3 kg per unit.

A humanoid is mostly gearboxes, motors and magnets. So the interesting question is not who builds the robots, but who sells to everyone building them.

That turns out to be a short list. Strain wave gears for the precision joints, where Harmonic Drive Systems has something close to a monopoly. Cycloidal reducers for the legs, mostly Nabtesco. Servos from Yaskawa, integrated actuators from Nidec, on-robot vision from Ambarella, complete joint modules from Schaeffler. Underneath all of them, about 1.3 kg of rare-earth magnet per robot, roughly 90% of which the world buys from China.

So I built a dashboard for it: eighteen names across three tiers, repriced every morning, with the claims from the viral versions of this list checked one by one. Several do not survive contact with the filings.

Humanoid supply chain →

Research notes, not investment advice.