基于Unscented Kalman滤波的飞行器天文/地磁自主导航算法研究(英文)

Application of Unscented Kalman filter in celestial /geomagnetic autonomous navigation algorithm of aerocraft

针对地磁场模型精度低而引起的导航精度不高及基于轨道动力学方程的天文导航算法的局限性问题,提出了一种利用天文/地磁信息为观测量的飞行器自主导航方法,并建立了动力学方程,同时推导了观测方程。算法采用星光矢量与地磁矢量的夹角为观测量,采用UKF滤波器估计飞行器的速度和位置,并进行了仿真研究。仿真结果表明,该算法的精度要远高于单纯的地磁导航,滤波的收敛性和稳定性较好,导航误差不随时间累积,有工程应用价值。

The low accuracy of geomagnetic model would causes navigation accuracy insufficient and induces limitations when adopting celestial navigation method based on the orbital dynamics equation. To overcome these, an aircraft autonomous navigation method using celestial/geomagnetic information as measurements is put forward. Meanwhile the dynamics equations are established, and the observation equation is derived. This method takes the angle between starlight and geomagnetism vector as the observation value and uses the UKF algorithm to estimate the position and velocity. The simulation results demonstrate that this algorithm＇s navigation accuracy is far better than that of the geomagnetic navigation. In addition, the filter convergence and stability arc satisfactory, and the error does not accumulate with the time. In this light, this method is valuable for engineering application.