Automatic calibration of the 3D Vector Magnetometer

摘要

Embedded sensors are an emerging trend in mobile consumer devices.In this work a new algorithm is derived for the onboard calibration of three-axis magnetometers.The proposed calibration method is written in the sensor frame,and compensates for the combined effect of all linear time-invariant distortions,namely soft iron,hard iron,three-dimensional sensor non-orthogonally,scale factors,null-shift,arbitrary bias,among others.The new algorithm can be separated into two steps:In the first step,obtain the ellipsoid fitting parameters from comparing the difference between the measured value and the actual vector.In a second step,a calibration algorithm is adopted to compensate for magnetometers distortions.According to the model parameters the measured data is corrected to improve the precision of magnetometer.Simulation and experimental results with sensors data are presented and discussed,supporting the application of the algorithm to commercial and military platforms.