Abstract: Aiming at the pose measurement caused by non-cooperative targets in visual measurement that cannot provide cooperation information,the ICP(Iterative Closest Point) algorithm is used to register the point cloud down-sampling data acquired at different times to complete the relative pose measurement of the target.The point cloud data of the target at the current moment is obtained using the structure from motion algorithm and the feature point matching algorithms are compared based on threshold matching and optical flow matching method.The extracted feature points are reconstructed by triangulation.The relative pose changes of the object at different times are calculated by using the downsampling point cloud data.Experiments show that when the object rotates,the maximum error of the rotation angle using the ICP algorithm does not exceed 0.11º.

Key words: structure from motion, point cloud matching, point cloud downsampling, iterative closest point