测地激光陀螺仪的倾斜角误差分析

Tilt angle error analysis of geodetic laser gyroscope

摘要:

测地激光陀螺仪是测量地球自转角速度的重要工具,为世界时(universal time,UT1) 解算提供依据。环境变化会影响测地激光陀螺仪光学腔的几何形状,从而影响陀螺仪的测量精度。本文主要针对由测地激光陀螺仪平面倾斜带来的陀螺仪萨格奈克(Sagnac) 频差之误差进行研究,结合基本误差理论、坐标系理论,推导出倾斜对陀螺仪旋转角速度影响的理论模型；利用艾伦方差法(Allan deviation,AD) 分析3个实验室的倾斜数据,并根据分析结果对原始数据作去噪处理；在此基础上使用时间序列法建立倾斜误差补偿模型,将倾斜造成的角速度误差降低一个量级,使输出的Sagnac频差更接近理论值。表明通过构建合理的倾斜误差补偿模型,可以改善陀螺仪输出数据的噪声水平,为陀螺仪进一步优化运行环境及相关数据的处理方法提供参考。

Abstract:

The geodesic laser gyroscope is an important tool for measuring the angular velocity of the earth's rotation and provides the basis for the solution of universal time.Environmental changes will affect the geometry of the optical cavity of the geodesic laser gyroscope,which in turn affects the measurement accuracy of the gyroscope.This paper mainly focuses on the error of gyroscope Sagnac frequency difference brought by the tilt of the geodesic laser gyroscope plane.Based on the basic error theory and coordinate system theory,the theoretical model of the influence of tilt on the rotation angular velocity of gyroscope is derived.Allan deviation (AD) method is used to analyze the tilt data from three Laboratories. The raw data is denoised according to the analysis results.Based on this,a tilt error compensation model is developed by using the time series method.It reduces the angular velocity error from tilt by an order of magnitude,bringing the Sagnac output frequency difference closer to the theoretical value.It shows that the noise level of the gyroscope output data can be reduced by constructing a reasonable tilt error compensation model,and it provides a reference for further optimizing the operating environment of the gyroscope and the processing method of related data.