三轴地磁传感器误差的自适应校正方法

Automatic and adaptive calibration method of tri-axial magnetometer

针对复杂磁环境下地磁传感器测量精度不足的问题,在分析地磁传感器各种误差来源的基础上,建立完整形式的地磁传感器椭球误差模型,通过最小二乘估计法拟合得到椭球模型系数,利用椭球模型系数推导地磁传感器误差矩阵和偏移矢量,最后对地磁传感器磁环境下的输出数据进行校正。实验结果表明,校正后的磁场强度和实际磁场强度基本一致,盲区附近滚转角误差减小到5°,俯仰角误差减小到4°,除了盲区附近的位置,滚转角误差减小到2°,俯仰角误差减小到1°,测量精度提高了近10倍,基本能够满足简易制导弹药弹道修正的需求。

Aiming at the insufficient measurement precision problem of magnetometer in complex magnetic environ- ment ,based on the analysis of various error sources of the magnetorneter,a complete form ellipsoid error model of the magnetometer is established; the ellipsoid model coefficients are obtained with least square estimation fitting method, and the error matrix and offset vector of the magnetometer are derived using the ellipsoid model coefficients; finally, the output data of the magnetometer in magnetic environment are corrected. The experimental results show that the magnetic field intensity after correction is basically consistent with the actual magnetic field intensity. In the area around blind area,the roll angle error is reduced to 5° and the pitch angle error is reduced to 4°. In the other locations ,the roll angle error is reduced to 2° and the pitch angle error is reduced to 1 °. The measurement accuracy is improved nearly tenfold, which can satisfy the trajectory correction requirement of simple guidance ammunition.