基于改进四元数阻尼误差模型的SINS初始对准算法

SINS initial alignment algorithm based on improved quaternion damping error model

针对传统捷联惯导系统(strapdown inertial navigation system,SINS)四元数非线性误差模型存在坐标系不一致的问题,对姿态误差模型和速度误差模型进行改进,将误差矢量统一投影至计算导航坐标系下。此外,引入全球定位系统阻尼信息,在阻尼SINS解算基础上,结合四元数无迹估计器提出了一种改进四元数阻尼误差模型对准算法,可应用于系泊状态下的SINS初始对准。仿真和车载试验结果表明,在不同的大失准角下,该改进算法相比传统四元数阻尼误差模型对准算法和欧拉角阻尼误差模型对准算法,具有更好的对准精度、收敛速度以及稳定性。

Aiming at the coordinate-frame inconsistency in traditional quaternion nonlinear error model of strapdown inertial navigation system(SINS),the attitude error model and velocity error model are improved,the error vector is projected into the computational navigation coordinate frame.In addition,the damping information of global position system is introduced,based on the damping SINS calculation and unscented quaternion estimator,a novel alignment algorithm based on improved quaternion damping error model is proposed,which is applied to the initial alignment of SINS in mooring state.Simulation and vehicle test results show that the improved algorithm has better alignment accuracy,convergence speed and stability than the traditional quaternion damping error model alignment algorithm and Euler angle damping error model alignment algorithm under different large misalignment angles.