Improved Magnetic Tracking Method Based on Scalar Triangulation and Ranging

Magnetic tracking methods provide a radiation-free, contactless solution for real-time localization, making them widely applicable to medical diagnostics and robotic navigation. The scalar triangulation and ranging (STAR) method enables fast tracking of magnetic targets in the geomagnetic field, but its accuracy is limited by incomplete compensation of asphericity errors. This article investigates the main error sources of the conventional STAR method and introduces an improved approach that combines iterative correction with a novel magnetic gradient contraction to effectively mitigate asphericity errors. Simulations under various postures demonstrate that the proposed method achieves a positioning accuracy of 0.0008 m, an orientation accuracy of 0.31°, and a computation time of 67 µs, representing an improvement of over 40.9% compared with conventional methods. Furthermore, experiments conducted in a magnetically shielded room (MSR) validate the practical effectiveness of the proposed method in enhancing tracking accuracy.