一种激光陀螺捷联惯性导航系统级标定方法

A System-level Calibration Method for Laser Gyro SINS

为优化激光捷联惯性导航在卧式三轴转台上的系统级标定方案,设计了卧式三轴转台外环轴整周旋转对惯性测量单元(IMU)误差参数的激励方法。基于捷联惯性导航的误差方程,阐述了速度误差与IMU误差参数间的关系,从而建立IMU系统级标定模型。该模型具有加速度计误差参数仅反应在观测量北向分量、陀螺误差参数仅反应在观测量东向分量的特点,消除了加速度计和陀螺误差参数标定误差的相互影响。根据准D最优准则,设计了正二十面体12点计划的双轴位置单轴速率翻滚法,利用最小二乘法辨识出IMU的24项误差参数。通过给加速度计和陀螺加入不同测量噪声,对IMU标定模型进行仿真,结果表明该方法可抑制加速度计和陀螺的测量噪声对标定结果的影响。

An exciting method of rotating the turntable outer axis for an integer period is designed to optimize the system-level calibration method of calibrating a strapdown inertial navigation system(SINS)on the horizontal three-axis turntable.Based on the SINS error equation,the relationships among velocity errors and inertia measurement unit(IMU)errors are described,and a system-level calibration model of IMU is established.In the proposed model,the interaction effect of error parameters of accelerometer and gyro is avoided due to that the northward component contains the accelerometer errors and the eastward component contains the gyro errors only.According to the quasi-D optimal criterion,a 12-point plan of the icosahedron is designed,and 24 error terms of IMU are identified by least square method when one axis runs in the speed mode and the other axes run in the position mode.The simulated results show that the influences of the accelerometer and gyro measurement noises on the system-level calibration results are effectively restrained,and the error terms are identified accurately.