Tracking a Millimeter-Scale Magnetic Source Under Embedded System Constraints

This study introduces an innovative method for submillimeter-scale accuracy magnetic flux density measurement with embedded system constraints, designed to enhance the localization and tracking of magnetic sources, particularly in the near-field region. Traditional approaches, often based on the dipole model, struggle with accuracy when the magnet is close to the sensor, a scenario recently motivated by key issues encountered in aerodynamics applications. The proposed method addresses several challenges, including model inaccuracy, sensor nonlinearity, the nonorthogonality of Hall plates within triple-axis chips, and issues related to the spatial separation of Hall plates and the determination of the virtual origin of the measurement system. It also considers discrepancies in the estimation of the magnetic source properties, such as variations in magnetization strength and orientation. It integrates an advanced theoretical model suitable for various magnetic source shapes and distances, considering all potential error sources simultaneously. The calibration procedure is demonstrated to be a crucial component to reach the targeted accuracy.