Frameless torque motors for humanoid joints
Michael Joseph · Founder, Iapyx Labs
Updated September 7, 2026
Frameless torque motors remain the default for high-torque humanoid joints (hips, knees), with coreless/hollow-cup motors used for hands and wrists. Western suppliers (Kollmorgen, NMB/MinebeaMitsumi) compete against Chinese vertically integrated players such as CubeMars/Sanrui, and third-party analysts size the humanoid-specific frameless motor segment in the low hundreds of millions of dollars today.
Key findings
- A market study published 11 July 2026 values the frameless torque motor for humanoid robot rotating joint market at US$171 million in 2025, projecting US$797 million by 2032 (24.9% CAGR, 2026-2032).
- A China humanoid supply-chain tracker (20 March 2026) reports four motor types dominate current Chinese humanoids: frameless torque motors for high-torque joints like hips and knees, plus coreless cup, hollow cup and related motors for lightweight, fast-response hand and wrist joints.
- CubeMars, a brand of Sanrui Intelligent, states it designs and manufactures compact high-torque planetary modules and frameless motors in-house with 17 years of R&D history.
- Kollmorgen cites RobCo scaling its modular robotics platform using TBM2G frameless torque motors for robot joints.
- NMB Technologies (MinebeaMitsumi) markets frameless BLDC motors positioned for direct integration into humanoid joint assemblies without an outer casing.
Sources
- https://www.openpr.com/news/4573871/frameless-torque-motor-for-humanoid-robot-rotating-joint-market
- https://robotics.techbuzzchina.com/reports/actuators-motors.html
- https://www.cubemars.com/categorys/humanoid-robot-motor
- https://www.kollmorgen.com/en-us/solutions/robotics/humanoid-robots
- https://nmbtc.com/blog/robotic-joint-design-frameless-motors/