捷联惯导系统大失准角下的初始对准研究

摘要

SINS (Strap- down Inertial Navigation System) nonlinear error model is built based on the concept of Euler platform error angles with large misalignment angles.A simplified UKF (Unscented Kalman Filter) filter method is applied to the initial alignment of SINS when the state equation is the non- linear and the observed equation is linear for the additive noise dynamic equation.The initial alignment of SINS with large misalignment angles is simulated under the static base.The simulation result showed that the simplified UKF was higher at the estimation precisian than EKF (Extended Kalman Filter) with misalignment angles being bigger.And it is a very practical method at the initial alignment of SINS with large misalignment angles.%针对捷联惯导系统初始对准过程中的大失准角情况,建立了基于欧拉平台误差角概念的捷联惯导系统(SINS)非线性误差模型,对于具有加性噪声的动态方程,当状态方程为非线性而观测方程为线性时,将一种简化的UKF滤波方法运用到捷联惯导系统初始对准中,并在静基座下对捷联惯导系统大失准角初始对准进行了仿真.仿真结果表明,随着失准角的增大,简化的UKF比EKF估计精度更高,是一种在进行捷联惯导系统大失准角条件下的初始对准时实用方法.