为了解决在轨维护和轨道垃圾清除中非合作目标的识别问题,提出了基于立体视觉的位姿(位置和姿态)测量方法。采用中值滤波器对原始图像进行平滑,去除星空背景干扰和其它噪声;将Canny边沿检测器用于对平滑后的图像进行检测,得到包含边沿信息的二值图像。然后,对该二值图像进行Hough变换,提取待识别对象的直线特征,并计算直线间的交点。最后,对所提取的左、右相机图像的点特征进行3D重构,得到各点在世界坐标系中的坐标,并据此建立目标坐标系,求出其相对于世界坐标系的位置和姿态。仿真结果表明,对于较远距离(〉2.5m),位置测量精度优于40mm,而近距离内(〈2.0m)优于10mm,相对姿态精度优于2°,基本满足对非合作目标进行跟踪、接近、绕飞等位姿测量要求。
A stereo vision-based method was proposed to measure the relative poses (position and attitude) between the two non-cooperative spacecrafts to solve the problem of the non-cooperative target recognition for the on-orbital maintenance and space debris removal A median filter was used to smooth the original images by removing the disturbance of orbital background and other noises. The edges in the smoothed images were detected using the Canny edge detector to obtain the corresponding binary images. Then, the straight lines of the object to be recognized were extracted from the binary images through Hough transform, and the intersection points among these lines were determined. Fially, the feature points in the left and right images were reconstructed in 3D to obtain the coordinates of the object points in the world frame. Based on these points, the target frame was defined and the pose of the target with respect to the world frame was determined. Simulation results indicate that the position errors are lower than 40 mm in the farther distance (〉2.5 m) and 10 mm in the nearer distance (〈2.0 m), and the orientation errors are less than 2°,which satisfies the requirements of pose measurements during tracking, approaching and flying round the non-cooperative target.