航姿系统矢量场传感器校正的双内积法

Dual Inner Products Calibration Method for Tri-Axial Vector Field Sensors in Attitude and Heading Reference System

三轴磁强计与加速度计广泛用于航姿系统中,针对其误差补偿问题,提出一种基于双内积的校正方法。该方法利用了地磁场和重力矢量自身模值守恒,以及二者在旋转轴上投影的不变性。该方法能克服基于椭球拟合的校正方法无法补偿非对准误差的缺陷,实现三轴磁强计及加速度计的完全校正。实验结果表明,该方法能有效改善航姿系统的精度且操作简便。

A novel calibration method for tri-axial magnetometer and accelerometer that widely used in attitude and heading reference system is proposed,which is based on dual inner products. The proposed method makes use of the invariance of geomagnetic and gravity vectors’ norms,as well as the constant projections of geomagnetic and gravity vectors on rotation axis. This method can eliminate the mutual misalignment that cannot be identified using the ellipsoid fitting method,and thus it can achieve complete calibration of tri-axial magnetometer and accelerometer. Experiment results show that the proposed method can effectively enhance the accuracy of attitude and heading reference system with simplified operations.