基于虚拟圆球法向量的极区惯性导航算法

Polar navigation algorithm for INS based on virtual sphere n-vector

提出了一种基于虚拟圆球法向量位置表示的具有全球范围适用性的惯性导航算法。避免了横坐标系、格网坐标系极区导航算法中参考椭球模型下曲率半径近似计算带来的误差问题,且不需要在极区算法和非极区算法之间进行复杂的切换。与地球坐标系下惯性导航算法相比,由于高度通道和水平通道的导航解算分开,便于通过阻尼抑制高度通道的误差发散问题。分别建立了高度通道和水平通道的误差微分方程,对极区和非极区惯性导航进行了统一的更加精确的误差特性分析。基于实际航海导航试验数据的仿真结果表明,相比横坐标系、格网坐标系极区导航算法,提出的极区导航算法形式简洁易实现,精度略高,且具有全球适用性。

An inertial navigation algorithm with global applicability is presented,in which position is represented by the normal vector(n-vector)based on a virtual sphere model.Compared with the polar region navigation algorithms based on the grid and transversal frame,the proposed algorithm avoids the errors produced by approximate calculation of curvature radius under reference ellipsoid model,and avoids complicated algorithm switching between polar and non-polar regions.Compared with the inertial navigation algorithm in Earth-frame,the proposed algorithm is easy to suppress the error divergence of the vertical channel by damping because the navigation solutions of the vertical channel and the horizontal channel are separated.Error differential equations for vertical and level channels are established separately,and a more accurate and unified error characteristic analysis is performed for the inertial navigation in both polar and non-polar regions.The simulation results based on real marine inertial navigation data show that compared with the polar region navigation algorithms based on grid and transversal frame,the proposed polar navigation algorithm is simple to implement and has higher accuracy,conciseness and global applicability.