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A Restricted 4PCS Algorithm for Registering Low Overlap Point Cloud

Registration algorithms align different point clouds from different views of an object by finding matching points and then transferring them into a reference coordinate system. The well-known 4PCS algorithm is a robust technique used for this purpose. Usually, 4PCS running time increases with the rise of the number of points in point clouds. We can reduce the runtime by using the K-means clustering algorithm to down-sample point cloud and decrease the number of points to the desired count. Unfortunately, when the overlap region between two adjacent point clouds decreases, the chance to find matching points is reduced even when there is no noise. To overcome this problem, we propose the Restricted4PCS (R- 4PCS) algorithm, in which the candidate four-point sets are restricted to be in a predefined distance. The simulation results show that the proposed algorithm works at least three times faster with better accuracy even when the overlapped area is as low as 20 percent.