Three-dimension Reconstruction Of Complicated Surface Based On Point Clound Data

Reverse engineering is a new discipline, which colligates modern design method,computer-Aided measurement,CAGD (computer-Aided Geometric Design ),CAD(Computer-Aided Design),CAM (Computer-Aided Made ).Material object reverse engineering of this thesis discussed refer to reconstruct the CAD modeling from the measured material object data, then use these models for analyses and manufacture of the products. Surface reconstruction is one of key techniques in reverse engineering. Based on the actual needs of surface remodeling from unorganized discrete points set, this dissertation studied some related technologies, such as data measurement, measured data preprocessing, surface reconstruction and so on. These technologies will make the research on reverse engineering versatile and perfect. The main research contents and achievement are as follows:A method for smooth planar contour fitting based on discrete data is presented in this thesis, and a method for complicated planar contour fitting is presented too:1) First all the data points used in the contour are ordered; 2) After calculating the curvature of each contour point, the points with bigger curvature are taken as feature points; 3) The contour is segmented by feature points; 4) The contour is globally constructed through determining the segments types (line or circle) and the constraints with the neighbor segments. 5) Based on section line, Surface is constructed through MengMian method.The reconstruction algorithm is presented in detail in the forth chapter, which include the computing of axis and the reconstruction of generatrix. Then two examples are given to show the effectiveness and veracity of the algorithm.Through the measuring of the wheel of the washing machine, several kinds of measuring method has been introduced and analyzed in this article and the optical measurement principle and procedure has been introduced in detail. Through the data measuring, data proposal and modeling of the wheel of the washing machine, This thesis has got through a technical line from ATOS to Imageware and CAD common software (UG) in practice, finally the author has realized the three-dimension reconstruction in UG software platform and has carried on precision analysis and numerical control emulation.