一种改进的磁罗盘罗差校准方法

磁罗盘作为一种导航设备广泛应用于飞行器、车辆等的导航系统，但其会受到周围铁磁物质的影响产生罗差，降低导航精度。传统的磁罗盘罗差校准采用最小二乘椭圆拟合校准算法，但该算法存在系数矩阵易奇异导致算法不稳定的问题。本文通过对系数矩阵的奇异性进行分析，提出了改进的最小二乘椭圆拟合算法，克服了原有算法的不稳定性问题，同时该算法将六维特征矢量的求解转化为三维特征矢量求解，在保证校准精度的情况下降低了计算量。实验结果验证了此方法的快速性和有效性，校准后的磁罗盘精度由0.8°提高到0.4°左右，满足了导航系统的需求。

An Improved Calibration Method Applied on Magnetic Compass Deviation

As a kind of navigation equipment, magnetic compass was widely applied in the navigation systems of flight vehicles, but it was always disturbed by ferromagnetic material to produce the magnetic deviation. The traditional magnetic compass deviation calibration generally adapted the least squares ellipse fitting calibration algorithm, but the coefficient matrix of this algorithm may be singular which caused the algorithm unstable question. By analyzing the singularity of the coefficient matrix, an improved least squares ellipse fitting calibration algorithm was proposed to solve the unstable question of conventional algorithm. Simultaneously this algorithm transformed six dimensional eigenvector's solution to the three dimensional eigenvector's solution, reduced the computation load while keeping the precise. The experimental results shown the rapidity and validity of this algorithm and the magnetic compass precision improved from 0.8° to 0.4°, meeting the requirements of the navigation system after calibration.