航姿参考系统三轴磁强计校正的点积不变法

Dot product invariance method for the calibration of three-axis magnetometer in attitude and heading reference system

为改善航姿参考系统中三轴磁强计校正精度,提出了一种基于泊松模型以及矢量点积不变性的校正方法。该方法利用地磁场矢量与一辅助矢量的点积为常数,无需本地地磁场精确数据,能完全确定泊松模型中的12个补偿系数,并能同时实现三轴磁强计的坐标系对准。针对辅助矢量的不同选择对该方法校正结果的影响,在电子罗盘上进行了实验验证及讨论。实验结果表明,该方法可使电子罗盘航向误差均方值减小到0.1°。

To improve the accuracy of threeaxis magnetometer calibration in attitude and heading reference system （AHRS）, a calibration method based on Poisson＇s model and dot product invariance is presented in this paper. Using an auxiliary vector that the dot product of the auxiliary vector and the geomagnetic vector is constant, the proposed method can completely determine the 12 compensation coefficients in Poisson＇s model without precise local geomagnetic information, and can simultaneously implement the alignment of threeaxis magnetometer coordinate sys tem. The experiment verification on an electronic compass was carried out. Experiment results demonstrate the impacts of different selections of the auxiliary vector on the calibration result; and using the proposed method, the re sidual heading error of the electronic compass can be reduced to 0.1°.