速率方位惯性平台/计程仪/重力匹配组合导航系统仿真研究

Simulation of Rate Azimuth Inertial Platform/Log/Gravity Matching Integrated Navigation System

根据重力无源导航的基本要求,建立了速率方位惯性平台/计程仪/重力匹配组合导航系统的工作模式,给出了该组合导航系统的误差状态方程、测量方程和扩展Kalman方程。由于重力传感器是在运动载体上测量重力的,其输出包含当地重力大小和厄特弗斯效应,所以在该组合导航系统Kalman滤波器中考虑了厄特弗斯效应。采用matlab/simulink工具对该组合导航系统在分辨率为0.005o×0.00 5o的数字重力异常图上进行了计算机仿真研究。仿真结果表明:该组合导航系统长时间定位误差小于导航系统目标误差的15%(RMS),在重力异常显著变化地区其定位误差将更小。

To meet the basic requirement of gravity passive navigation, the paper presents the operating modes of Integrated Navigation System of Rate Azimuth Inertial Platform/Log/Gravity Matching, and its error state equations, measurement equations and extended Kalman equations are given. When onboard gravity sensor measures gravity, its output includes both local measurement gravity and the Eotvos effect, so the Eotvos effect would be considered in Kalman filtering of the integrated navigation system. The simulation of the integrated navigation system was carried out with Matlab/Simulink and gravity anomaly maps whose resolution is 0.005＇×0.005＇. Simulation results show that the position error of the integrated navigation system is less than 15% （RMS） of goal error over long intervals, and even smaller in the area with evident anomaly gravity.