无陀螺捷联惯导系统静基座粗对准实用方法

Practical coarse alignment method of GFSINS on stationary base

基于一种六加速度计配置方案,给出了载体加速度和角速度的解算公式,并分析了无陀螺捷联惯导系统粗对准原理。在静基座下,针对系统初始对准前得不到载体角速度初始值而导致地球自转角速度在载体坐标系上的分量无法获得的情况,提出了一种可行的、具有实用价值的非完全自主式粗对准方案。依靠外部航向设备得到初始方位姿态,通过加速度计敏感的重力矢量输出获得初始水平姿态,进而解算出载体初始捷联矩阵。误差分析表明,方位粗对准精度不超过2°,水平粗调精度在0.3°以内。

Based on a six-accelerometer configuration scheme, the calculation formula of accelerometer and angular velocity was given, and the coarse alignment theory of gyroscope free strapdown inertial navigation system （GFSINS） was analyzed. Since the earth rotation rate couldn＇t be obtained on stationary base because the initial value of angular velocity was unknown before initial alignment, a feasible and practical non-independent coarse alignment scheme was put forward. The initial azimuth was derived from the external course device, and the initial level attitude was calculated from the gravity sensed by the accelerometer, and then the initial strapdown matrix was obtained. The analysis of error shows that the precision of coarse alignment for azimuth and level is respectively less than 2° and 0.3°.