激光陀螺捷联惯组角动态误差分析及其抑制方法

Angle Dynamic Error Analysis and Suppression Methods of Strapdown Inertial Measurement Unit Based on Ring Laser Gyroscope

二频机抖激光陀螺捷联惯组在高动态载体上的角动态误差日渐成为影响其应用精度提升的重要因素。针对此问题,从各陀螺抖动耦合激励惯性敏感器本体组件圆锥运动产生误差,以及载体过载、振动环境引起陀螺敏感轴弯曲变形摆动产生单表级圆锥误差两个方面,对激光陀螺动态误差进行了理论分析。结合工程应用实际情况,分别对两项误差进行计算和仿真,得出理论误差可达0.01(°)/h以上,必须进行抑制的结论。根据误差产生机理,总结了合理配置各陀螺抖动频率和提升陀螺敏感轴弯曲刚度以抑制其弯曲变形的措施,并给出了抑制效果,可为提升激光陀螺捷联惯组角动态精度提供参考。

The angular dynamic error of two frequency mechanically dithered ring laser gyro(RLG)strapdown inertial unit on high dynamic carrier has increasingly become an important factor that influences the improvement of its application accuracy.To solve this problem,the dynamic error of inertial sensor assembly excited by gyro dithering coupling,and the meter-level conical error produced by bending,deformation and swings of gyro sensitive axis led by carrier overload and vibration environment are analyzed theoretically.Combined with the practical situation of engineering application,the two errors are calculated and simulated respectively.It is concluded that the error reaches more than 0.01(°)/h and should be suppressed.Based on the mechanism of error generation,the measures that rationally configure the gyro dither frequency and enhance the bending stiffness of gyro sensitive axis to suppress its bending deformation are summarized,and the sippressing effect is presented,which can be used as a reference for the improvement of the angular dynamic accuracy of RLG strapdown inertial navigation system.