基于正逆向解算的单轴旋转惯导参数辨识方法

The Forward and Backward Processes Algorithm for Identifying Parameter in Single-axis Rotation Inertial Navigation System

在单轴旋转惯导系统中,z向旋转轴陀螺漂移由于不能被旋转调制成影响系统导航性能的主要误差因素。另外,为了缓解对准过程中对准精度与对准时间的矛盾,在有限的对准时间内最大程度的保证对准精度并能够辨识出z轴陀螺漂移,该文提出了一种静基座条件下,基于时间正逆向解算算法并通过增加航向角量测量,利用最小二乘法进行参数辨识的快速对准方法。该算法不仅能缩短对准时间,还能快速估计z轴陀螺漂移,提高导航精度。以现有的单轴旋转光纤陀螺惯导系统进行试验,结果表明,误差补偿后,系统定位精度提高了约24%,定位误差小于2 n mile/12 h。

In single-axis rotation inertial navigation system(SRINS),the z-axis gyro drift(εz)dramatically limits its navigation precision because it cannot be modulated by rotation.In addition,in the process of alignment,in order to alleviate the contradiction between the alignment accuracy and the alignment time,and guarantee the alignment accuracy to the greatest extent and identify the z-axis gyro drift within a limited alignment time,a fast alignment method based on the time forward and reverse algorithm in stationary base is proposed,which can identify the parameters by using the least square method by adding the azimuth angle into the measurement in this study.This algorithm can not only reduce the alignment time,but also quickly estimate the z-axis gyro drift and improve the navigation accuracy.The experiment on a SRINS with FOGs is carried out.The results show that after the error compensation,the positioning accuracy of the SRINS is improved by about 24%and the positioning error is less than 2 n mile/12 h.