极区飞行间接格网惯性导航算法

Indirect grid inertial navigation mechanization for transpolar aircraft

为克服极区经线收敛引起的惯导系统定位定向难题,同时为实现中低纬度地区和高纬度地区导航算法形式的统一,提出了以游移方位惯导编排为内核的极区间接格网导航算法。推导了游移坐标系和格网坐标系间的方向余弦矩阵,以此可间接获取格网航向和格网速度,同时用地心地固坐标替换经纬高定位参数,解决了极区的导航定位问题。仿真分析了两组特定飞行轨迹下的算法性能,并与直接格网惯导力学编排算法进行了比较,结果表明二者导航精度相当,可满足极区导航的需要。

The indirect grid inertial navigation elements based on wander azimuth mechanization for transpolar flight is presented. First of all, the direction cosine matrix（DCM） from the wander frame to the grid frame is derived. The DCM allows the grid heading and grid velocity be obtained indirectly from wander navigation parameters in high latitude regions, while the heading and velocity are in the manner of truth north heading and geographical velocity from wander navigation parameters in low latitude regions. The earth-centered earthfixed coordinates can be indirectly calculated and directly applicable to aircraft positioning as an alternative to the use of longitude-latitude coordinates in the Polar Regions. Simulation results show that the navigation performance is the same as the direct grid mechanization. The presented approach can solve the polar navigation problems, and the inner mechanization is the same in precision as low latitude inertial navigation elements.