The Research Of Disposal And Model Reconstruction Of Scattered Points In Reverse Engineering (RE)

Reverse Engineering is one of the methods for digital product development. It shortens exploitation period, improves precision and is an important way to create and develope a new product by digesting and absorbing advanced technologys.Presently, there are two aspects in research of RE: one is system integration, which includes the integration of all taches of RE and the exploitation of common software; the other one is research on the pivotal technology of RE, which includes data acquiring, data dealing and model reconstruction. Data acquiring is the basis of RE; Data dealing, which is the crucial tache of RE, will affect the result of model reconstruction; Model reconstruction is the ending. On account of that, this thesis will focus on data dealing and model reconstruction.Firstly, The method of data acquiring is expounded. The different point cloud are compared. Scattered point cloud is investigated in this thesis. Secondly, the crucial technologys are analyzed, such as founding the relationship of scattered point, transferring between global coordination and local coordination, filtration and reduction of scattered point and extracting boundary feature. Then a new method for model reconstruction is put forward based on the traditional methods in modeling. The creative points of this thesis is as follows:> In order to keep the important feature of surface by using curvature, A new arithmetic that reduce data according to curvature directly is put forward. Octree is used to speed up searching neighborhood of points. Then the curvature of points is calculated by using CT arithmetic. Finally different value is used in different sub region to reduce the point data.> Combined with laminating theory in Rapid Modeling, a new method to reconstruct model by line homotopy is bring forward.