基于激光陀螺自适应补偿的船体变形测量方法

Ship hull angular measurement method based on adaptive compensation for laser gyroscope output

基于长期变形、动态挠曲变形以及陀螺随机零偏的状态方程,构建了激光陀螺测量的惯性姿态匹配最优滤波器,可以实时地估计出船体变形角。针对实时估计的长期变形角具有偏置误差的问题,推导了惯性姿态匹配的误差方程,指出动态挠曲变形角与船体惯性姿态角之间具有长时间的交叉相关耦合作用导致了长期变形角估计具有偏置误差,并提出了对输入到最优滤波器的激光陀螺角增量进行自适应补偿的方法来抑制偏置误差。实验结果表明,补偿后俯仰角、横滚角和艏挠角的偏置误差均方根均小于5″,较补偿前降低均方根误差约为5″,该自适应补偿方法可有效地抑制偏置误差,提高惯性姿态匹配方法在船体变形测量应用中的有效性。

An optimal filter for inertial attitude matching measurement by laser gyroscopes is constructed to determine the ship hull angular deformation in real-time, which is based on state functions of long-term deformation, dynamic flexure and gyro＇s bias error. In view of the bias error of long-term deformation estimation in real-time filtering, the error equation of inertial attitude matching measurement is derived, which denotes that the statistical cross-correlation coupling effect between dynamic flexure and inertial attitude angle fully accounts for the bias error of long-term deformation estimation. Then an adaptive compensation method for laser gyroscope＇s output in optimal filter is introduced. Experiment results show that the angular deformation RMSEs in pitch, roll and azimuth directions are lower than 5″. This adaptive compensation method can effectively restrain the bias error and improve the engineering practicability in angular deformation measurement application.