A framework from point clouds to workpieces

Abstract

Combining computer-aided design and computer numerical control (CNC) with global technical connections have become interesting topics in the manufacturing industry. A framework was implemented that includes point clouds to workpieces and consists of a mesh generation from geometric data, optimal surface segmentation for CNC, and tool path planning with a certified scallop height. The latest methods were introduced into the mesh generation with implicit geometric regularization and total generalized variation. Once the mesh model was obtained, a fast and robust optimal surface segmentation method is provided by establishing a weighted graph and searching for the minimum spanning tree of the graph for extraordinary points. This method is easy to implement, and the number of segmented patches can be controlled while preserving the sharp features of the workpiece. Finally, a contour parallel tool-path with a confined scallop height is generated on each patch based on B-spline fitting. Experimental results show that the proposed framework is effective and robust.

SECAD-Net: Self-Supervised CAD Reconstruction by Learning Sketch-Extrude Operations

“…Over the past decades, reverse engineering has been extensively studied; it aims at converting measured data (a surface mesh or a point cloud) into solid 3D models that can be further edited and manufactured by industries. Traditional approaches addressing this problem consist of the following tasks: (1) segmentation of the point clouds/meshes [5,41,60], (2) fitting of parametric primitives to segmented regions [11,36,55],…”

A method for fast reconstruction of closed section workpiece surface using point clouds

“…These methods avoided complex algorithms and achieved fast reconstruction but introduces uncertainty and significant pre-training costs. Furthermore, the methods of directly generating machining toolpath without surface reconstruction are proposed, such as Shen et al 18 constructed workpiece mesh models based on the point cloud and generated toolpaths based on these mesh models and Wang et al 19 proposed a direct planning method of robot toolpaths based on the field-measured point clouds. These methods are dependent on the local accuracy of meshes and point clouds, which sacrifices the smoothness of the stitching and the overall coordination.…”

A Theoretically Complete Surface Segmentation Method for CNC Subtractive Fabrication

“…Unfortunately, their method does not apply to subtractive fabrication. Shen et al [16] developed a new surface segmentation algorithm that can effectively preserve the sharp features using minimum spanning tree. But they did not consider the fabrication constraints.…”