一种基于罗经效应的SINS初始对准精度评估方法

An initial alignment accuracy evaluation method of SINS based on the gyro compass effect

关键词:  捷联惯导系统(SINS)  初始对准  方位精度评估  陀螺罗经效应

Key words:  Strapdown inertial navigation system(SINS)  Initial alignment  Azimuth accuracy evaluation  Gyro compass effect

摘要:

针对在惯性器件误差、标定误差和基座晃动干扰误差等复杂因素下难以评价惯导初始对准精度的问题，基于经典陀螺罗经效应初始对准原理，提出了从导航解算速度误差随时间变化的二次多项式中辨识并评估方位对准精度的方法。根据运动的相对性特点，将不可测量和补偿的晃动基座线运动干扰等效为惯性器件误差，使得改进的方位对准精度评估方法既适用于静基座也适用于晃动基座，全面覆盖了陀螺误差、加速度计误差、惯组标定误差、晃动基座干扰误差及其他一切不明机理误差等因素的影响。在静基座、海上停泊基座及转台摇摆基座３种典型工况下进行了实验验证，主要分析了惯性器件精度、初始对准时长和基座干扰强度对方位对准精度的影响，分析方法和结论具有良好的工程应用参考价值。

Abstract:

To address the challenge of evaluating the initial alignment accuracy of inertial navigation systems under complex factors such as inertial device errors, calibration errors， and base shaking interference errors, a novel method based on the classical gyro compass effect initial alignment principle is proposed. This new method aims to evaluate the azimuth alignment accuracy by analyzing the quadratic polynomial of the navigation solution velocity error over time. By exploiting the relative motion characteristics, the unmeasured and uncompensated interference caused by the base‘s linear motion is treated as an equivalent error of the inertial device. The proposed method, which is applicable to both static and shaking bases, provides a comprehensive evaluation of the alignment accuracy by incorporating various sources of error, including gyroscope errors, accelerometer errors, inertial measurement unit calibration errors, base shaking interference errors, and errors due to unknown mechanisms. Experiments are conducted to evaluate the azimuth alignment accuracy under three typical working conditions of static base, offshore mooring base and turntable swing base. The main analysis focuses on the effects of inertial device accuracy, initial alignment time， and base interference intensity on azimuth alignment accuracy. The analysis methods and conclusions provide valuable references for practical engineering applications.