一种车载激光捷联惯组免拆卸标定方法

A Free Disassembly Calibration Method for Strapdown Inertial Navigation System Based on the Vehicle

陀螺和加速度计常值零偏随时间变化,惯组误差增大,不满足部队使用要求。传统方法是将激光捷联惯组从载车上拆卸下来放在高精度三轴转台上重新标定,过程繁琐费时、成本高,不利于部队的使用和快速反应。设计了一种激光捷联惯组免拆卸标定方法,在载车进行四位置转位,每个位置静止10min的条件下对陀螺和加速度计零偏误差进行了全局可观测性分析,证明了陀螺常值零偏和水平加速度计常值零偏是可观测的。利用Kalman滤波器估计了三只陀螺和水平加速度计常值零偏。对标定补偿前后激光捷联惯组的全方位对准精度和1h导航精度进行了比较。结果表明:基于载车四位置转位免拆卸标定方法对陀螺和加速度计常值零偏估计是有效的。

The SINS fixed on the vehicle is not calibrated after being used for a long time,the constant bias of gyro and accelerometer will deviate from the values calibrated in the laboratories,leading to the accuracy of all-round alignment and the accuracy of navigation don't meet the need of user.According to the traditional calibration methods of SINS,the SINS need to remove from vehicle and fix the SINS on high-precision three-axis turntable,the whole process consume time,cost highly,and is not conducive to the daily training and the rapid reaction.A free disassembly calibration method is designed.Under the condition of the vehicle,four position inversions and ten minutes standstill in each position the global observability of error parameter is analyzed,and the observability of the constant bias is proved.Making use of the Kalman filter estimates the constant bias of gyro and accelerometer.The accuracy of all-round alignment and the accuracy of navigation before and after the calibration are compared;the result indicates that the free disassembly calibration method that estimates the constant bias of gyro and accelerometer based on the vehicle four position inversions is effective.