Motion systems / 02← All architectures
Quasi-direct-drive actuator
A large-diameter outer-rotor motor works with a single low-ratio planetary stage for responsive, backdrivable motion.
01 / Inside the architectureOuter-rotor joint actuator
3D model and components
Preparing architecture…
Power path
Inverter → outer rotor → sun gear → planets → output carrier
Inspect the components
Select a component to identify its function in the assembly.
02 / ComponentsFunction of every part
What each part does.
Power path: Inverter → outer rotor → sun gear → planets → output carrier.
- FOC drive & encoder
- Current control and position feedback regulate the motor and joint.
- Outer-rotor PMSM
- The magnet-lined rotor bell turns around a stator mounted on the fixed hub.
- Low-ratio planetary
- The rotor drives the sun; planets mesh with the fixed internal ring and turn the carrier.
- Output bearing
- The supported carrier carries external loads into the housing.
- Carrier & flange
- The carrier combines the planet reactions into useful joint output torque.
- Fixed hub & housing
- The fixed hub supports the stator and provides its thermal path.
03 / Where it is usedRelevant application areas
Machines that call for it.
01
Humanoid & legged robotics
Walking, balancing and manipulation bring many controlled axes together. Mass and heat at each joint influence the capability of the whole robot.
See the application 02Mobile robotics & logistics
Legged platforms meet changing contact forces with joint torque control. Efficient, responsive axes help the machine adapt without carrying unnecessary joint mass.
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