Robot joint reducers directly affect positioning accuracy, payload and durability. The two dominant technologies are harmonic drives and RV (cycloidal) reducers.

Harmonic Reducers

Ideal for collaborative robots and light payload arms. They offer compact size, near-zero backlash (arc-minute level) and high reduction ratios (50:1 to 160:1) in a single stage. Cost is moderate and precision is excellent.

RV Reducers

Built for heavy payload industrial robots (10kg and above). They deliver high torque density, strong stiffness and long life, but are typically larger, heavier and more expensive than harmonic units.

How to Decide

Map your robot's maximum payload and required repeatability first. For load below 5kg with heavy emphasis on compactness, choose harmonic. For payload above 10kg in a 24/7 production line, RV is the safer bet. Always request backlash and efficiency test reports from the supplier.