四元数UKF超紧密组合导航滤波方法

针对GPS/SINS(Global Positioning System/Strapdown Inertial Navigation Sys-tem)超紧密组合导航系统线性化滤波在高动态、弱GPS信号等环境下性能下降严重的问题,提出了一种以四元数UKF(Unscented Kalman Filter)为基础的GPS/SINS超紧密组合导航系统非线性滤波方法.通过分析GPS与SINS在超紧密组合导航系统中的关系,提出了一种利用SINS信息来估计、修正GPS载波信号的方法,在此基础上建立了组合导航滤波的状态方程和量测方程;以四元数乘性误差模型为基础,提出了一种可应用于UKF滤波的求解四元数加权均值的方法;提出了基于四元数UKF的GPS/SINS超紧密组合导航滤波方法.仿真实验表明:在高动态环境下,四元数UKF滤波方法增强了GPS/SINS超紧密组合导航系统的定位精度和抗干扰能力.

Quaternion unscented Kalman filtering for ultra-tight integration

Concerning the problem of the ultra-tightly coupled global positioning system/strapdown inertial navigation system (GPS/SINS) degraded in high dynamic and weak signal environments for linear filter, a quaternion unscented Kalman filter method was proposed. Firstly, analyzing the relationship between GPS and SINS of the ultra-tightly coupled GPS/SINS navigation system, an algorithm that using the SINS to estimate and correct the carrier signal of the GPS was derived, then the state and measurement equations was built. Secondly, concerning the problems of singularity and frequent parameter transformation for Rodrigus method, based on the multiplicative quaternion error model, a weighted averaging quaternion method that using the quaternion directly was proposed. Finally, the quaternion unscented Kalman filter method was proposed for the ultra-tightly coupled GPS/SINS navigation system. The simulation results indicate that the quaternion unsecured Kalman filter method is more robust to jamming and increases the position accuracy in high dynamic.