Singularities in Parametric Meshing
نویسندگان
چکیده
A parametric meshing technique is presented with special emphasis to singularities in the parametric mapping. Singularities are locations where the parametric mapping is highly distorted or even singular. In a NURBS context, this arises when control points are clustered into the same location in three dimensions. Limitations of parametric plane meshing in this context are highlighted, and zeroand first-order surface approximations are commented. In the context of the DOD CREATE-MG project, different CAD kernels and mesh generators communicate as plugins through application programming interfaces (API) . The parametric mesh generator is coupled to the CAD through the Capstone APIs and is independent of a particular CAD kernel. Some CAD kernels do not allow these geometrical constructions while some tolerate it. It is therefore a necessity to handle these degenerate cases properly. Examples illustrate the method ’s capabilities.
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