Research On Feature Surface Reconstruction In Reverse Engineering

Surface reconstruction is one key technology in reverse engineering. A feature surface reconstruction is systematically studied in this dissertation.This dissertation studied the methods of data's pre-treatment and presented algorithm of 3D mesh segmentation: Using the curvature and vector to detect the sharp feature and the region growing method to segment the triangle meshes.This dissertation presented the algorithm of feature surface recognition based on quadric surface fitting and geometry property. Firstly using quadric surface to fit with given surface and calculate the error metric to identify free surface and general quadric surface. Secondly computing geometry property of each point on Gaussian Sphere and Curvature Coordinate. The distribution will identify each kind of quadric surface and blend surface. In order to improve the efficiency this algorithm calculates approximation distance from point to surface and make priority to identify planes. This algorithm is easy to recognize plane, cylinder, cone, sphere, blend surface and free surface.This dissertation also presented the algorithm of parameterization surface reconstruction. For quadric surface, feature parameterization is extracted by surface fitting, for free surface, using Coons method to build up base surface from and split up base surface vertically and horizontally into grids and project the grid points onto contours and reconstruct NURBS surface.Finally, this dissertation integrated the reverse engineering and conventional engineering and presented the strategy of integration CAD model.