关键词: B样条, 卷曲模型, 曲面重构, 散乱点集, 组合曲面

Abstract: For the large wrap-around surface, it is difficult to parameterize the data due to without obvious rectangular boundaries. Meanwhile, the modeling process is inefficient since it involves frequent manual operations. Therefore, a method of combined B-spline surface reconstruction is proposed. First, a method of recognizing the projection axis from sampled points is given, and these points in physical space are projected to two-dimensional space by using the mapping method. Consequently, the boundary curve is divided into four boundary curve segments according to the characteristic of the boundary curve, and then region segmentations and quick parameterizations of points are realized by utilizing Coons surface forms. B-spline surface patches are further reconstructed from segmented point sets. This modeling strategy is very helpful to improving the efficiency and automation of modeling process. In addition, in the process of constructing combined surfaces, a smooth blending method with G1 geometric continuity is provided between two adjacent patches. Examples verify the feasibility and validity of the proposed modeling and blending methods for combined surface reconstruction.

Key words: B-spline, Combined surfaces, Scattered points, Surface reconstruction, Wrap-around model