Mechanical
Wrist Unit
Houses the final wrist axis motors, reducers, and seals that position and orient the tool mounting flange.
The wrist unit combines the last few axes of motion, typically pitch and roll or pitch, yaw, and roll depending on the robot's kinematic design, into one dense mechanical assembly at the end of the forearm.
Because so many moving parts share a small housing, the wrist unit is lubricated as a system, and service manuals usually specify a shared grease type and change interval rather than treating each internal reducer separately.
Wrist units are also the most common place for seal failures to show up, since the assembly has more shaft penetrations in a smaller space than any other part of the arm.
Common questions
- What does the Wrist Unit do?
- Houses the final wrist axis motors, reducers, and seals that position and orient the tool mounting flange.
- How does the Wrist Unit fail?
- Common failure modes: Internal seal failure leading to grease leakage, Combined backlash across multiple wrist axes affecting accuracy, Overheating from densely packed motors in a confined space, Contamination ingress through a damaged seal or gasket.
- What fault codes relate to the Wrist Unit?
- Related codes include SRVO-021.