Method and system for a self-calibrated multi-magnetometer platform

摘要

A multi-magnetometer device comprises at least two z-axis aligned and physically rotated magnetometer triads utilized for measuring corresponding earth's magnetic field. The magnetic field measurements are utilized to measure rotation measurements of a single orthogonal axis along the 360 degrees of the complete circle without user's assistance and/or magnetometer movement for magnetometer calibration. The multi-magnetometer device may compute its magnetic heading utilizing the magnetic field measurements if no magnetic perturbations are detected. When magnetic perturbations are detected, a perturbation mitigation process may be performed. The rotation measurements may be generated by selectively combining the magnetic field measurements. Hard-iron components are determined utilizing the rotation measurements, and are removed from the magnetic field measurements. Soft-iron components are determined utilizing the hard-iron free magnetic field measurements, and are removed from the hard-iron free magnetic field measurements. The resulting perturbation free magnetic field measurements are utilized to compute magnetic heading.

主权项

1. A method for removing a magnetic perturbation from magnetic field measurements in a multi-magnetometer device that comprises at least two magnetometers, said at least two magnetometers being aligned along an axis in a three dimensional coordinate system, the method comprising:
incrementally rotating said at least two magnetometers in a plane of said three dimensional coordinate system; measuring a magnetic field along a complete circle around said axis in said three dimensional coordinate system while said at least two magnetometers are being incrementally rotated; incrementally combining said magnetic field measurements taken, at different time instants, by different magnetometers from among said at least two magnetometers to simulate a rotation of a single orthogonal axis along the complete circle around said axis in said three dimensional coordinate system; detecting said magnetic perturbation within said combined magnetic field measurements; and removing said magnetic perturbation from said combined magnetic field measurements when detected.