一种高精度动基座传递对准方法

A High-accuracy Transfer Alignment Method Under Moving Base

在动基座传递对准过程中,主、子惯导间的挠曲变形是影响子惯导对准精度的主要误差因素。传统的传递对准方法通常将挠曲变形等效为经验的马尔可夫模型,当实际的挠曲变形与经验模型的匹配度较低时,便会导致传递对准精度下降。为此,提出了一种不依赖于挠曲变形经验模型的高精度传递对准方法。首先,推导并建立了挠曲变形与主/子惯导陀螺仪测量的角速度之间的内在关系,利用主/子惯导陀螺仪测量得到的角速度信息,直接计算得到挠曲变形的粗略值;其次,推导了挠曲变形的计算误差与陀螺仪误差之间的耦合关系,建立了一种不依赖于挠曲变形经验模型的新型传递对准系统模型;进而,利用最优估计算法对挠曲变形的计算误差进行精确估计与补偿。仿真验证表明,所提方法能够精确补偿复杂的挠曲变形,从而实现高精度的动基座传递对准。

During the transfer alignment under moving base,the flexible deformation between the master and slave inertial navigation systems(INSs)is the primary error factor affecting the alignment accuracy of the slave INS.In traditional transfer alignment methods,flexible deformation is usually equated to empirical Markov models.However,a low match between actual flexible deformation and the empirical model can lead to a decrease in transfer alignment accuracy.Therefore,a high-accuracy transfer alignment method without relying on empirical model of flexible deformation is proposed.Firstly,the intrinsic relationship between the flexible deformation and the angular velocities measured by master/slave gyroscopes is derived and established.Thus,the rough value of flexible deformation is directly calculated using the measured angular velocities.Then,the coupling relationship between the calculation error of flexible deformation and the gyroscope error is derived,and a novel transfer alignment system model that does not rely on empirical models of flexible deformation is established.Furthermore,the optimal estimation algorithm is used to accurately estimate and correct the calculation error of flexible deformation.Simulation results show that the proposed method can accurately compensate the complex flexible deformation,thereby achieving high-accuracy transfer alignment under moving base.