Automatic positioning and 3D scanning of parts based on point laser scanning

In order to provide contour data of machining surfaces for parts processing systems, a point laser based automatic positioning and 3D scanning method for parts is proposed. Using robots equipped with point laser sensors for automatic positioning and 3D scanning of parts, the center of a single positioning hole of the part is first obtained through 10 point positioning method and least squares fitting method. Then, the precise position and angle of the part in the machine coordinate system are determined through the center of two positioning holes. After the part positioning is completed, 3D scanning work is carried out to plan the S-shaped scanning path of the part under the principle of minimum tolerance. Then, the raw point cloud obtained from the scanning is preprocessed. Finally, the contour data of the part to be machined is obtained through boundary extraction based on normal estimation and clustering segmentation based on Euclidean distance. Through experiments, the average absolute deviation of 50 sets of automatic positioning was measured to be within 50 μ m, which meets the expected target of automatic positioning. The part point cloud can also accurately extract the contour data of the part to be machined surface through pre-processing, appropriate parameter boundary extraction, and clustering segmentation, laying a good foundation for subsequent part machining.