---
title: "Actuator bills of materials"
description: "Three actuator teardowns (Tesla Optimus roller-screw linear actuator, Unitree quasi-direct-drive motor, strain-wave cobot joint): what is inside, who makes each part, cost against raw material (the idiot index) and who keeps the margin, every number cited."
canonical: https://actuatorlist.com/bom
last-updated: 2026-11-07
---
# Actuator bills of materials

Three actuator teardowns (Tesla Optimus roller-screw linear actuator, Unitree quasi-direct-drive motor, strain-wave cobot joint): what is inside, who makes each part, cost against raw material (the idiot index) and who keeps the margin, every number cited. As of November 2026. Interactive page: https://actuatorlist.com/bom. JSON: https://actuatorlist.com/api/v1/bom.

## Cases

| Case | Price | Raw material | Idiot index | Largest gross profit (share of price) | Robots | Finding |
| --- | --- | --- | --- | --- | --- | --- |
| [Tesla Optimus linear actuator](https://actuatorlist.com/bom/optimus-linear.md) (`optimus-linear`) | ~$0.44-1.1k[^1][^2] (estimate, 2024) | $4.38 | 176x | Sanhua Intelligent Controls 28.4% | Optimus Gen 2, Forerunner K2 (same design) | About two thirds of what the assembler spends is the roller screw, a few hundred grams of bearing steel turned into a precision part. |
| [Unitree GO-M8010-6 joint motor](https://actuatorlist.com/bom/unitree-qdd.md) (`unitree-qdd`) | $369[^3] | $3.13 | 118x | Unitree Robotics 60.1% | Go1, X1 (same design), K-Bot (same design) | No supplier margin sits between the metal and the shelf: the bought-in chips come to about $4, and almost everything else is Unitree's own step. |
| [Strain-wave cobot joint](https://actuatorlist.com/bom/harmonic-frameless.md) (`harmonic-frameless`) | $1.44k[^4] | $5.27 | 273x | Harmonic Drive Systems 15.6% | Optimus Gen 2 (same design), Asimov 1 (same design) | Half the price is the strain-wave gear, whose steel costs about ten cents; its incumbent maker keeps nearly a third of what it charges. |

Idiot index is the price over the cost of the raw materials inside, at 2026-09 prices. Most part costs are models from published shares, so read them as estimates.

## Sources

[^1]: Huibo research (via Zhihu), "Optimus hardware BOM: rotary actuators CNY 57k, linear actuators CNY 44k, hands CNY 20k". https://zhuanlan.zhihu.com/p/687045590 (not opened). Paywalled.
[^2]: XenoSpectrum (on Morgan Stanley), "Optimus Gen 2 BOM about $55k, actuators 56% of it". https://xenospectrum.com/en/humanoid-robot-bom-actuator-cost/ (not opened). Paywalled.
[^3]: Unitree, "GO-M8010-6 Motor (Unitree shop)". https://shop.unitree.com/products/go1-motor (not opened).
[^4]: RCDrone, "ZeroErr eRob 80 T integrated joint (shop listing)". https://rcdrone.top/products/zeroerr-erob-80-t-motor (not opened).