PMSM Joint Actuator · serves as: Joint Actuation, Locomotion Drive.
Which group T-Motor AK80-9 belongs to and how it is built
A subcategory covering joint actuators — integrated drive units combining a motor, gearbox, encoder, and control electronics in a single module, used in the joints of robot limbs and torsos.
A PMSM (Permanent Magnet Synchronous Motor) joint actuator is an integrated drive module that uses a permanent magnet synchronous motor to provide precise position, velocity, and torque control at robot joints. It offers high power density, low losses, and deterministic torque response, making it a popular choice in robotic manipulators, exoskeletons, and humanoid robots. The unit typically integrates an encoder, gearbox, and motor controller into a single compact assembly.
The T-Motor AK80-9 (also sold as CubeMars AK80-9) is a quasi-direct drive integrated actuator module combining a BLDC motor, a 9:1 planetary gearbox, an on-board FOC (Field-Oriented Control) driver, and an absolute encoder in a single compact housing.
The module communicates over a 1 Mbaud CAN bus and supports torque, velocity, and position control modes. Its low inertia and high bandwidth have made it a popular choice for legged robotics research — most notably in the MIT Mini Cheetah platform. Peak output torque is 18 Nm.
