单轴旋转惯导系统中陀螺漂移的精确校准

摘要

基于惯导系统的误差传播特性和轴向陀螺对经纬度误差的影响规律,提出了精确校准轴向陀螺漂移的方法以解决在单轴旋转惯导系统中单轴旋转只能自动补偿与转轴垂直的陀螺漂移,不能补偿轴向陀螺漂移的问题.首先,介绍了单轴旋转惯导系统自动补偿的基本原理.然后,在静基座的条件下分析了轴向陀螺漂移、初始方位和姿态角误差、初始速度误差等对经纬度的影响规律.提出了一种利用经纬度误差作为观测量,采用最小二乘法对轴向陀螺漂移进行精确校准的新方法.最后,利用激光陀螺单轴旋转惯导系统进行了静态导航试验和跑车试验.实验结果显示,该方法对轴向陀螺漂移的辨识精度达到o.000 5(°)/h,系统的定位精度优于1 nm/72 h.该方法能够有效地辨识轴向陀螺漂移,使系统达到较高的导航精度,具有很强的工程实用价值.%On the basis of error propagation characteristics of an Inertial Navigation System(INS) and the effect of axial Ring Laser Gyroscope(RLG) on the errors of longitude and latitude, a calibrating method for the RLG drift was proposed to solve the problems that single-axis rotation could compensate the vertical RLG errors automatically, but could not compensate the axial RLG errors in a single-axis rotation INS. First, the auto-compensation principle of the single-axis rotation INS was introduced briefly. Then, the effect of the axial RLG drift, initial heading and attitude error, and initial velocity error on the longitude and the latitude was analyzed on the stationary base. Depending on the errors of longitude and latitude, a new method based on the least squares was proposed to calibrate the RLD drift precisely. Finally, the static and vehicle navigation experiments were performed. The results show that the identification precision reaches 0. 000 5 O/h and radial position error of the INS is less than 1 nm/72 h. The axial RLG drift can be calibrated precisely by the least square method proposed and the experiment result of navigation meets practical demands.