基于IEKF序列图像分析的航天器相对状态测量方法

The Method for the Determining Relative State Between Spacecrafts Based on a IEKF Image Sequence Analysis

提出了一种基于IEKF序列图像分析的航天器间相对状态单目视觉测量方法.该方法利用具有正方形几何结构的4个目标特征点在物体坐标系中的空间坐标及它们在像平面上成像点的图像坐标,根据估计理论,采用迭代扩展卡尔曼滤波(iterated extended Kalman filter, IEKF )方法解算出目标航天器与图像传感器的相对状态.试验结果表明:该方法不仅使作用距离大大提高,而且极大地提高了测量的稳定性.该测量方法可直接用于航天器编队飞行及空间站交会对接过程、空间监视、目标拦截等应用领域中航天器间相对状态测量.

The paper proposes a method of determining the relative states between spacecrafts based on IEKF image sequence analysis and monocular computer vision. According to the estimate theory, the 3D object coordinates and 2D image coordinates are used to compute the relative states between target spacecrafts and image sensor by the iterative extended Kalman filter(IEKF). The experiment results testified that this method can not only increase the effect distance of the system, but also enhance its stabilization. The method will be widely used in many fields such as formation flying of spacecrafts, rendezvous docking with space station, space surveillance and the target holding up.