Kollmorgen

A long-established US motion-control maker whose frameless torque motors are common in robot joints.

Kollmorgen traces back to periscope designs by the German optics expert Friedrich Kollmorgen, and was incorporated in New York in 1916; it is now headquartered in Radford, Virginia, and marked its 110th anniversary in 2026. It has changed hands several times: owned by Danaher, then spun off in 2016 into Fortive (itself a Danaher spinoff), folded into Altra Industrial Motion in 2018, and became a brand under Regal Rexnord after it acquired Altra in 2023. Its main products are servo motors, drivers, and frameless torque motors, and it also makes navigation control systems for AGVs. A frameless motor is sold as just a stator and rotor, which a robot maker mounts directly inside its own joint housing — well suited to the compact joints of collaborative arms and humanoid robots; its TBM2G series is designed specifically for humanoid robot joints.

ExampleA humanoid robot's rotary joints commonly use a frameless motor like Kollmorgen's TBM2G, paired with a harmonic reducer and dual encoders to form a joint actuator module.

Related

Frameless Torque Motor · Servo Motor · Joint Actuator Module · Strain Wave Gear (Harmonic Drive) · maxon · Core Components

Sources

Kollmorgen: History
Regal Rexnord and Altra receipt of regulatory approvals for merger
艾邦机器人：无框力矩电机全球23家供应商 (Chinese)

As of

2026