Hardware

Cross-Roller Bearing

A cross-roller bearing is a compact rotary bearing in which cylindrical rollers are arranged alternately at 90 degrees to each other in a single V-groove raceway, allowing one bearing to support radial, axial, and moment loads simultaneously with high rigidity. This makes them standard as the output bearing of robot joints, integrated into harmonic drive units, and in rotary tables, where they resist tilting moments from cantilevered arm loads.

Why it matters for physical AI

Joint stiffness and moment capacity set achievable end-effector precision under load, so output bearing quality quietly bounds the repeatability that learned fine-manipulation skills can exploit.