Hardware
Hollow Shaft
A hollow shaft is a rotating shaft with a central bore, used in robot joints and actuators so that cables, pneumatic lines, or optical fibers can be routed through the axis of rotation rather than around it. Hollow-shaft harmonic drives, frameless motors, and slip rings are common in serial arms, keeping wiring internal and eliminating external cable loops that snag or fatigue.
Why it matters for physical AI
Internal cable routing is what allows continuous-rotation joints and clean arm exteriors, directly improving reliability and workspace safety in robots that run around the clock in cluttered environments.
Related terms
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