公开(公告)号：US11200351B2

公开(公告)日：2021-12-14

申请号：US17059469

申请日：2020-06-13

Applicant: HUAZHONG UNIVERSITY OF SCIENCE AND TECHNOLOGY

Inventor： Wenlong Li ,  Cheng Jiang ,  Gang Wang ,  Zelong Peng ,  Han Ding

IPC: G06F30/10 ,  G06T17/30 ,  G06K9/62 ,  G09C1/00

Abstract: The disclosure discloses a method for constructing actual processing curve of part with small curvature based on a point cloud boundary. The method includes: (a) encrypting a three-dimensional ordered boundary curve of a part to be processed; (b) fitting encrypted boundary points into a plane, and projecting each boundary point into the plane to obtain a projection point; (c) performing Euclidean cluster within the plane to obtain point sets, and fitting the obtained point sets into a straight line; (d) performing the Euclidean cluster on projection points that are not fitted into the straight line to obtain corner point sets, and fitting a sharp corner or a rounded corner of the corner point sets to obtain a fitted boundary curve within the plane; (e) mapping the fitted boundary curve to a curved surface of the three-dimensional ordered boundary curve to obtain an actual processing curve of the part to be processed.

公开(公告)号：US11106932B2

公开(公告)日：2021-08-31

申请号：US17059474

申请日：2020-06-13

Applicant: HUAZHONG UNIVERSITY OF SCIENCE AND TECHNOLOGY

Inventor： Wenlong Li ,  Cheng Jiang ,  Gang Wang ,  Zelong Peng ,  Han Ding

IPC: G06K9/00 ,  G06K9/46 ,  G06K9/62

Abstract: The disclosure discloses a method for extracting a boundary of a thin-walled part with small curvature based on three-dimensional point cloud. The method includes: collecting point cloud data of a part to reduce density of the point cloud data, performing Euclidean cluster to divide into point cloud pieces, obtaining triangular mesh surfaces for each point cloud triangulation; extracting a boundary vertex of each triangular mesh surface to obtain a contour thereof, selecting a contour of the part among all contours; searching with each point on the contour as a center to form a three-dimensional boundary point cloud band; projecting the three-dimensional boundary point cloud band to a plane, orderly extracting two-dimensional boundary points within the plane, and arranging corresponding points in the three-dimensional boundary point cloud band according to an order of ordered boundary points within the plane to obtain ordered boundary points in the three-dimensional boundary point cloud band.

公开(公告)号：US11359905B2

公开(公告)日：2022-06-14

申请号：US16116468

申请日：2018-08-29

Applicant: Huazhong University of Science and Technology

Inventor： Huan Zhao ,  Hao Li ,  Han Ding ,  Sijie Yan ,  Xiaoming Zhang ,  Xiaojian Zhang

IPC: G01B5/012 ,  G01B3/00 ,  G01B5/008 ,  G01L5/22 ,  G06F3/0354 ,  G01B21/20 ,  G01B5/20 ,  G01L5/16

Abstract: A complex surface three-coordinate measuring device includes a three-degree-of-freedom motion platform and a force control probe, the force control probe is fixedly mounted on the Z-axis sliding block, which is in the same direction as the X-axis direction and used to contact with the workpiece surface with constant force. A six-axis force sensor is used to collect the contact force between the stylus and the workpiece surface. In this method, the force control is realized in the measurement to make the stylus in constant force contact with the workpiece surface. The error compensation direction is determined according to the direction of the contact force, and then the effective radius of the stylus spherical head is compensated in this direction, thus the actual contact point of stylus and workpiece can be obtained.