[Show abstract][Hide abstract] ABSTRACT: This paper describes a new fast Reverse Engineering (RE) method for creating a 3D computerized model from an unorganized cloud of points. The proposed method is derived directly from the problems and difficulties currently associated with remote design over the Internet, such as accuracy, transmission time and representation at different levels of abstraction. With the proposed method, 3D models suitable for distributed design systems can be reconstructed in real time. The mesh reconstruction approach is based on aggregating very large scale 3D scanned data into a Hierarchical Space Decomposition Model (HSDM), realized by the Octree data structure. Then, a Connectivity Graph (CG) is extracted and filled with facets. The HSDM can represent both the boundary surface and the interior volume of an object. Based on the proposed volumetric model, the surface reconstruction process becomes robust and stable with respect to sampling noise. Moreover, the data received from different surface/volume sampling devices can be handled naturally. The hierarchical structure of the proposed volumetric model enables data reduction, while preserving significant geometrical features and object topology. As a result, reconstruction and transmission over the network are efficient. Furthermore, the hierarchical representation provides a capability for extracting models at desired levels of detail, thus enabling designers to collaborate at any product development stage: draft or detailed design.
Full-text · Article · Aug 2004 · Computer-Aided Design
[Show abstract][Hide abstract] ABSTRACT: 3D scanners developed over the past several decades have facilitated the reconstruction of complicated engineering parts. Typically the boundary representation of a part is reconstructed from its scanned cloud of points. This approach, however, is still limited and cannot be applied to a family of objects such as thin parts. Recently, new 3D scanning devices have been developed. These devices capture additional information, such as normals and texture, as well as conventional information, including clouds of sampled points.This paper describes a new and fast reverse engineering method for creating a 3D computerized model from data captured by contemporary 3D scanning devices. The proposed method aggregates large-scale 3D scanned data into an extended Hierarchical Space Decomposition Model (HSDM) based on Octree data structure. This model can represent both an object's boundary surface and its interior volume. Based on the proposed volumetric model, the surface reconstruction process becomes more robust and stable with respect to sampling noise. The hierarchical structure of the proposed volumetric model enables data reduction, while preserving sharp geometrical features and object topology. As a result of data reduction, the execution time of the reconstruction process is significantly reduced. Moreover, the proposed model naturally allows multiresolution surface reconstruction, represented by a mesh with regular properties. The proposed surface reconstruction approach is based on extracting a Connectivity Graph from the extended HSDM and reconstructing facets based on normals data. The feasibility of the method will be demonstrated on a number of complex objects, including thin parts.