# What a humanoid is made of

> A dashboard for the humanoid supply chain: the suppliers selling to almost everyone building robots, repriced every morning
- **Author**: Nader Cserny
- **Published**: 2026-08-31
- **URL**: https://nader.io/posts/what-a-humanoid-is-made-of

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<a href="https://nader.io/projects/robotics-analysis"><img src="/projects/robotics-analysis/og.webp" alt="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." class="post-hero" /></a>

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 ->](https://nader.io/projects/robotics-analysis)**

Research notes, not investment advice.

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