Font Size: a A A

Algorithms For Minimum Distance Between NURBS Surfaces And Their Implementations

Posted on:2005-10-18Degree:MasterType:Thesis
Country:ChinaCandidate:P JiangFull Text:PDF
GTID:2168360122475783Subject:Computational Mathematics
Abstract/Summary:PDF Full Text Request
This thesis proposes two algorithms for the minimum distance between general NURBS surfaces respectively.Firstly, based upon the technique of splitting the NURBS surfaces and bounding containers, a Split Algorithm is applied to calculate the minimum distance between two general NURBS surfaces. Then, incremental algorithm for convex hull and GJK algorithm are employed to improve the Spilt Algorithm's performance. Then, the thought of uniform-cost search is applied to improve the algorithm. The implement shows that the improved Split Algorithm is more quickly.Secondly, the Genetic Algorithm is employed to calculate the minimum distance between two general NURBS surfaces. Then, two methods are applied to keep the diversified variety of colony: reserve two special units in new population and increase the mutation factor. This makes it possible to approach the global optimal value with less number of units. In comparison with the Standard Genetic Algorithm, this enhanced Genetic Algorithm is more quickly and reliably.Finally, this paper makes comparison between these two algorithms, and estimates the computational complexity of these algorithms and points out the disadvantage and advantage of these two algorithms. Many examples are calculated using these two algorithms.The programs of the above algorithms are developed by C++ language. It is showed that the algorithms are robust and efficient by computation the minimum distance between NURBS surfaces.
Keywords/Search Tags:minimum distance, NURBS surfaces, Incremental Algorithm, Convex Hull, GJK Algorithm, split of NURBS surface, Genetic Algorithm
PDF Full Text Request
Related items