Based On The Breakdown Of The Complex Surface Reconstruction Technology

The appropriate surface reconstruction method is the key for the quality of reverse engineering, which is an important research issue of reverse engineering. The conventional surface reconstruction techniques can only deal with surfaces with simple general topology. For complex surfaces, it is difficult to handle the inter-patch joint to maintain continuity among neighboring surfaces. This shortage can be remedied by the reconstruction techniques of subdivision surface with arbitrary topology, which can ensure the whole continuity of the model automatically and without any joint, so it is more suitable for complex surfaces reconstruction. Several topics are researched in the thesis, such as subdivision method, mesh simplification and optimization, remeshing, surface reconstruction, reconstruction result analysis,system development and so on. A detailed list as follow:(1) In order to avoid the weakness that the model features are failure to maintained as well as the grid number grows at a speed of 4 times in the progress of Loop subdivision, an effective adaptive Loop subdivision scheme is proposed, which can maintain the feature of the model and reduce the quantity of the triangles.(2) An improved mesh simplification algorithm is proposed, by which the feature of the simplified mesh and the fine triangle shape can be keep, and the optimization algorithm is embed to the process of simplification. The experimental results show that a high quality and less quantity mesh is produced after the iterative simplification.(3) A subdivision remeshing approach based on shrink wrapping is researched. In this approach, remeshing is achieved by using attractive force and relaxation force iterative to adjustment mesh position, the direction which from the vertex in the sub-mesh to its nearest vertex in the base-mesh is taken as the direction of the attraction force, and the distance between the two vertex is regarded as the value of the attraction force; the tangential of Laplacian operator is made as relaxation force.(4) The iterative method is used in subdivision surface reconstruct- ion, after being compared with the iterative fitting method. Then the reconstruction error is displayed vividly by color interpolation technique.(5) Based on the algorithms described above, a subdivision surface reconstruction system is developed. With the standard file exchange interfaces for points cloud and STL format document, the system can be integrated with other commercial CAD/CAM software conveniently.