捷联惯导摇摆基座自对准中圆锥误差补偿算法

Coning Error Compensation Algorithm of SINS Self-Alignment on Swaying Base

针对捷联惯导系统(SINS)在摇摆基座上的自对准误差,提出了减小圆锥误差、提高自对准精度的具体圆锥误差补偿算法。分析比较了四元数四阶龙格-库塔算法、等效转动矢量的二子样、三子样等圆锥误差补偿算法及其理论补偿效果。结合仿真和实验结果得出:自对准误差随算法子样数的增大而降低,子样数增加1,北向对准误差减小近1倍,姿态角的离散度降低;随摇摆幅度的增大和频率的提高,三子样补偿算法的自对准精度接近稳定;综合考虑采样频率、子样数、计算量和对准精度要求,选择三子样圆锥误差补偿算法可以满足SINS摇摆基座下的自对准要求。

Coning error compensation algorithm in the process of self-alignment is put forward in light of the strapdown intertial navigation system （SINS） self-alignment error on swaying base. It reduces coning error and increases the self-alignment accuracy. The quaternion fourth-order Runge-Kutta algorithm and two-sample and three-sample and other error compensation algorithm of equivalent rotation vector and their theoretical compensation effect are analyzed and compared in theory; through simulation and experi- ments, it is obtained that the self-alignment error decreases along with increasing of the number of sample. When the number of sample increases 1, the self-alignment error of north-angle is reduced nearly 1 time and the dispersibility of attitude angle is reduced; with the increasing of the swaying amplitude and frequency, the self-alignment accuracy of three-sample compensation algorithm is close to stability . Considering the sampling frequency and the number of sample and calculation and alignment accuracy, the three-sample coning error compensation algorithm should be selected and it can satisfy the self-alignment requirements of SINS on swaying base.