Parallel Generation of NC Tool Paths for Subdivision Surfaces

  • Dai Junfu (Dept. of Computer Science & Technology, Tsinghua University) ;
  • Wang Huawei (Dept. of Computer Science & Technology, Tsinghua University) ;
  • Qin Kaihuai (Dept. of Computer Science & Technology, Tsinghua University)
  • Published : 2004.12.01

Abstract

The subdivision surface is the limit of recursively refined polyhedral mesh. It is quite intuitive that the multi-resolution feature can be utilized to simplify generation of NC (Numerical Control) tool paths for rough machining. In this paper, a new method of parallel NC tool path generation for subdivision surfaces is presented. The basic idea of the method includes two steps: first, extending G-Buffer to a strip buffer (called S-Buffer) by dividing the working area into strips to generate NC tool paths for objects of large size; second, generating NC tool paths by parallel implementation of S-Buffer based on MPI (Message Passing Interface). Moreover, the recursion depth of the surface can be estimated for a user-specified error tolerance, so we substitute the polyhedral mesh for the limit surface during rough machining. Furthermore, we exploit the locality of S-Buffer and develop a dynamic division and load-balanced strategy to effectively parallelize S-Buffer.

Keywords

References

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