Calibration System and Algorithm Design for a Soft Hinged Micro Scanning Mirror with a Triaxial Hall Effect Sensor

TL;DR

This paper introduces a novel calibration system and algorithm for soft-hinged micro scanning mirrors that addresses out-of-plane translation challenges, achieving high pose estimation accuracy using a minimal setup.

Contribution

It presents a low-cost calibration rig and a reflection-based algorithm with a self-synchronizing model fitting approach for precise MSM pose measurement.

Findings

Achieved MSM pose estimation accuracy of 0.020°

Developed a minimal 2-laser calibration rig

Proposed a self-synchronizing periodicity-based calibration method

Abstract

Micro scanning mirrors (MSM) extend the range and field of view of LiDARs, medical imaging devices, and laser projectors. However, a new class of soft-hinged MSMs contains out-of-plane translation in addition to the 2 degree-of-freedom rotations, which presents a cabliration challenge. We report a new calibration system and algorithm design to address the challenge. In the calibration system, a new low-cost calibration rig design employs a minimal 2-laser beam approach. The new new algorithm builds on the reflection principle and an optimization approach to precisely measure MSM poses. To establish the mapping between Hall sensor readings and MSM poses, we propose a self-synchronizing periodicity-based model fitting calibration approach. We achieve an MSM poses estimation accuracy of 0.020{\deg} with a standard deviation of 0.011{\deg}.