A new local consistent mending scheme for complex freeform surface model was proposed,by the combined use of global beautification technique for freeform surface model and Nsided hole filling method,which was based on discretization of boundary conditions and trimmed Bspline surface model.Firstly, the infinitesimal deformation technique of differentiable manifold was used to beautify the multiple surfaces approximated to point cloud subject to tight error globally,which could generate convergent G1 smooth Bspline surfaces and improve the shape of the model.Secondly, the local region containing Npatch corner was clipped off the original multiple surfaces,and then the trimmed area based on discretization of boundary conditions and the trimmed Bspline surface model was reconstructed to satisfy the approximate G1 continuity with adjacent surfaces while reflecting the feature trend of the original surface.Practical applications illustrate that the presented local consistent mending technique can achieve the global G1 continuity and the shape preserving in the complex surface modeling and reverse engineering,as well as provide a stable and reliable basis for further research on topology recovery technique．
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