Hardware

Resolver

A resolver is an electromagnetic rotary transducer that measures absolute shaft angle through the varying transformer coupling between a rotor winding and two stator windings in quadrature, whose outputs encode the sine and cosine of the shaft angle. Being brushless, contactless, and free of optics and onboard electronics, resolvers tolerate temperature extremes, vibration, and radiation that disable optical encoders, at the cost of resolution and signal-conditioning complexity.

Why it matters for physical AI

Reliable joint sensing in harsh environments, from foundries to space, still favors resolvers, and their ruggedness illustrates the sensing trade-offs behind every actuator design choice.