基于欧拉角微分模型的捷联惯导直接非线性对准方法

从捷联惯性导航系统欧拉姿态角非线性微分方程出发,利用静态对准零速度约束条件研究了由姿态角、速度输出和传感器误差组成的直接非线性对准简化模型;同时,结合该对准模型系统方程非线性、量测方程线性的特点,对状态与系统噪声联合采样的复杂加性噪声UKF算法进行简化,实现状态扩维后计算量不增加.随后,通过M ATLAB仿真对传统欧拉...

SINS Direct Nonlinear Alignment Based on Euler Angle

An improved Strap-down Inertial Navigation System(SINS)nonlinear filtering alignment method based on Euler attitude angle differential equations was presented.Different from traditional nonlinear filter alignment,the dynamic model states directly contained Euler attitude angles,but attitude error angles.Considering the constraint of zero-velocity on static base,the simplified nonlinear model was derived,which reduces the computation;meanwhile,by consideration of the complexity additive system noise,and the feature of system equation nonlinear but measure equation linear,a simplified UKF was proposed here,which assured the computation consistent with traditional UKF before states augment.Subsequently,MATLAB simulations were carried out,in order to evaluate the alignment precision of traditional nonlinear alignment method and the direct nonlinear alignment algorithm proposed here,the results showed the validity of this simplified nonlinear model and the improved UKF.Finally,a certain number of engineering suggestions were given out for how to improve the nonlinear alignment accuracy and convergence speed.