MAGIC: Automatic Calibration of Magnetic Tracking

Abstract

Magnetic tracking systems measure the field produced by a permanent magnet to infer its position and orientation. However, real-world deployments are riddled with magnetic disturbances: ferromagnetic materials introduce hard-iron offsets, while electronic components create soft-iron distortions that vary by device and environment. These effects corrupt raw magnetometer readings and must be corrected before accurate tracking is possible.

MAGIC is a systematic calibration framework that automatically characterizes and compensates both soft- and hard-iron disturbances for MEMS magnetometer arrays. It requires no specialized equipment and no manual intervention — making magnetic tracking practical to deploy at scale.

Key Contributions

• Unified model for both soft-iron and hard-iron magnetic disturbances in magnetometer arrays.
• Fully automatic calibration — no specialized lab equipment or manual steps required.
• Demonstrated on MagX hand tracking platform, significantly improving tracking accuracy.
• Generalizable to any application relying on MEMS magnetometer measurements.

BibTeX

@inproceedings{wang2022magic,
  title     = {Automatic Calibration of Magnetic Tracking},
  author    = {Wang, Mingke and Luo, Qing and Iravantchi, Yasha and Chen, Xiaomeng and Sample, Alanson and Shin, Kang G. and Tian, Xiaohua and Wang, Xinbing and Chen, Dongyao},
  booktitle = {Proceedings of the 28th Annual International Conference on Mobile Computing and Networking (MobiCom)},
  year      = {2022},
  publisher = {ACM}
}