无人机导航系统中由磁、角速率和重力传感器组成的姿态测量系统容易受到干扰磁场观测的影响。本文设计了一种融合基于微机电系统的捷联惯导系统、重力场、地磁场和太阳矢量（太阳方向）信息的抗干扰综合导航联邦卡尔曼滤波器。过滤器根据环境条件或手动设置工作在融合复位或不复位模式下。此外，发现干扰磁场观测会干扰四元数的状态估计协方差矩阵，进而影响联邦滤波器无复位模式下估计四元数的融合更新。为了消除磁场观测对俯仰角和滚转角姿态信息的影响，设计了一种利用磁力计对四元数中偏航角分量进行修正更新的方法，并通过构造一个欧拉角信息融合方法开发了一种欧拉角信息融合方法。滤波器融合更新中欧拉角的伪协方差矩阵。因此，当存在干扰磁场观测且滤波器处于非复位模式时，融合更新后主滤波器的俯仰角和横滚角估计值不受影响，主滤波器偏航角估计误差相对于估计值减小由磁力计校正的子滤波器的误差。通过数值模拟和半实物模拟说明了该算法的有效性。
The attitude measurement systems composed of magnetic, angular rate and gravity sensors in the navigation system of an unmanned aerial vehicle are vulnerable to disturbed magnetic field observations. In this paper, an anti-interference integrated navigation federal Kalman filter is designed with fusing the information of microelectromechanical-system-based strapdown inertial navigation system, gravity field, geomagnetic field and solar vector (direction of sun). The filter works in the mode of fusion reset or no reset according to environmental conditions or manual setting. In addition, the characteristic is discovered that disturbed magnetic field observations can interfere with the state estimation covariance matrixes of quaternions, which in turn affect the fusion update of estimated quaternions in no reset mode of the federal filter. In order to eliminate the effect of magnetic field observations on the attitude information of pitch and roll angles, a method of correction update for a yaw angle component in quaternions using the magnetometer is designed, and an Euler angle information fusion method is developed by constructing a pseudo-covariance matrix of Euler angels in fusion update of the filter. Thus, when there exist disturbed magnetic field observations and the filter is in no reset mode, the estimated pitch and roll angles of the main filter after fusion update are not affected, and the yaw angle estimation errors of the main filter decrease relative to the estimation errors of the sub-filter which is corrected by a magnetometer. The effectiveness of the algorithm is illustrated by a numerical simulation and a semi-physical simulation.
