惯性/图像组合导航中的双模态双滤波器研究

在简要介绍了飞行器视觉图像定位导航原理及模型的基础上，针对其非线性模型的推广Kalman滤波的收敛与初始条件有关的问题，将其定位导航的两种模型（线性与非线性模型）组合，提出了双模态双滤波器滤波方法。这种滤波能很好地解决非线性推广Kalman滤波的收敛问题。通过第一个线性滤波器的滤波估计给第二个非线性滤波器提供滤波初值，使这一非线性滤波收敛，并能取得较高的滤波精度。

Study of two-mode and two-filter used in inertial/image integrated navigation

In this paper,the theory and mode of image based navigation are briefly introduced first.Since the mode of navigation is nonlinear,extended Kalman filter is used.The convergence of nonlinear Kalman filter is affected by its initial condition,so if the initial condition is not given properly,the nonlinear filter will divergent.The method of two mode and two filter is presented in this paper to solve this problem.It comes from the combining of two modes of navigation (linear and nonlinear mode).Since the first linear filter provides initial conditions for the second nonlinear filter,the nonlinear filter will converge.Through this new filter,high accuracy of estimation is obtained.