极区飞行格网惯性导航算法原理

Grid Mechanization in Inertial Navigation Systems for Transpolar Aircraft

为克服极区飞行时地理经线收敛引起传统机载惯性导航系统力学编排方案无法定位定向的问题,提出了格网坐标系下的惯导力学编排方案。该方案可以直接获得格网航向而无需任何外界参考信息,地心地固坐标系下的位置坐标替代传统经纬度坐标可直接用于飞机定位。推导的格网导航坐标系下的导航误差方程可方便用于组合导航算法设计。仿真分析表明格网导航算法误差特性同常规导航方案的误差特性一致,可以满足极区飞行时飞机的导航需要。

The convergence of geographic meridians at the poles makes steering and positioning extremely difficult if not impossible when utilizing conventional inertial navigation systems （INS） during high latitude flights. The grid coordinate frame mechanization of the inertial navigation system is presented to cope with above problems. The approach allows grid heading to be known directly, without reference to any external sources of information. The Earth-centered Earth-fixed （ECEF） coordinates can be directly applicable to aircraft positioning in the polar regions as an alternative to the use of longitude-latitude coordinates. The grid frame mechanization error equations are derived for integrated navigation systems. The simulation results and their analysis show preliminarily that the error characteristics for grid frame navigation proceed in exactly the same fashion as for the conventional navigation mechanization. The grid frame inertial navigation offers the solution to transpolar aircraft.