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arXiv · 2511.17608

Robot joint characterisation and control using a magneto-optical rotary encoder

Yunlong Guo·John Canning·Zenon Chaczko·Gang-Ding Peng
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Abstract

A robust and compact magneto-optical rotary encoder for the characterisation of robotic rotary joints is demonstrated. The system employs magnetic field-induced optical attenuation in a double-pass configuration using rotating nonuniform magnets around an optical circulator operating in reflection. The encoder tracks continuous 360{\deg} rotation with rotation sweep rates from {\nu} = 135 {\deg}/s to {\nu} = 370 {\deg}/s, and an angular resolution of {\Delta}{\theta} = 0.3{\deg}. This offers a low-cost and reliable alternative to conventional robot rotation encoders while maintaining competitive performance.

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Yunlong Guo, John Canning, Zenon Chaczko, Gang-Ding Peng. 2025-11-18. Robot joint characterisation and control using a magneto-optical rotary encoder. https://arxiv.org/abs/2511.17608

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