Contour Parallel Offset and Tool-Path Linking Algorithm for Pocketing Using Pairwise Intersection Approach

Pairwise Intersection 방식을 이용한 윤곽 오프셋 및 공구경로 연결 알고리즘

  • 허진헌 (경상대학교 대학원 산업시스템공학과) ;
  • 김영일 ((주)씨테크시스템, 경상대학교 대학원 산업시스템공학과) ;
  • 전차수 (경상대학교 산업시스템공학부)
  • Published : 2006.10.31

Abstract

Presented in this paper is a new fast and robust algorithm generating NC tool path for 2D pockets with islands. The input shapes are composed of line segments and circular arcs. The algorithm has two steps: creation of successive offset loops and linking the loops to a tool path. A modified pairwise technique is developed in order to speed up and stabilize the offset process, and the linking algorithm is focused on avoiding thin-wall cutting and minimizing tool retractions. The proposed algorithm has been implemented in C++ and some illustrative examples are presented to show the practical strength of the algorithm.

Keywords

References

  1. 김덕수, 'Polygon Offsetting for Pocket Machining of CAM Software', '94대한산업공학회논문집, 1994
  2. 김동수, '다면체 모델 가공을 위한 곡선기반 방법', 박사학위논문, 경상대학교, 2002
  3. 박상철, 정연찬, '포켓가공을 위한 오프셋 공구경로 연결 알고리즘', 한국 CAD/CAM학회 논문집, 제 6권, 제3호, pp. 169-173, 2001
  4. 정재훈, '복합곡면의 설계 및 가공경로 생성에 관한 연구', 석사학위논문, 포항공대, 1994
  5. Choi, B. K. and Kim, B. H., 'Die-Cavity Pocketing via Cutting Simulation', Computer Aided Design, Vol. 29, No. 12, pp. 837-846, 1997 https://doi.org/10.1016/S0010-4485(97)00031-6
  6. Hansen, A. and Arbab, F., 'An Algorithm for Generating NC Tool Paths for Arbitrarily Shaped Pockets with Islands', ACM Transactions on Graphics, Vol. 11, No.2, pp. 152-182, 1992 https://doi.org/10.1145/130826.130832
  7. Held, M., 'On the Computational Geometry of Pocket Machining', Springer-Verlag, 1991
  8. Tawfik, T. and Ahmed, E., 'A Sweep-line Algorithm and Its Application to Spiral Pocketing', International Journal of CAD/CAM, Vol. 2, No.3, pp. 32-40,2002
  9. Tiller, W. and Hanson, E. G., 'Offsets of Two dimensional Profiles', IEEE Computer Graphics and Applications, CGA(4), No.9, pp. 36-46, September 1984
  10. Yang, S. N. and Huang, M. L., 'A New Offsetting Algorithm Based on Tracing Technique', '93 ACM Solid Modeling Symposium, Montreal, Canada, pp. 201-210, 1993
  11. Norman L. Jones, Michael J, Kennard, Alan K. Zundel, 'Fast Algorithm for Generating Sorted Contour Strings', Computers & Geosciences, Vol. 26, No.7, pp. 831-837, August 2000 https://doi.org/10.1016/S0098-3004(00)00009-1
  12. Persson, H., 'NC Machining of Arbitrarily Shaped Pockets', Computer Aided Design, Vol. 10, No.3, pp. 169-174, May 1997 https://doi.org/10.1016/0010-4485(78)90141-0
  13. Choi, B. K. and Park, S. C., 'A Pair-wise Offset Algorithm for 2D Point-sequence Curve', Computer Aided Design, Vol. 31, No. 12, pp. 735-745, October 1999 https://doi.org/10.1016/S0010-4485(99)00060-3
  14. Park, S. C. and Chung, Y. C., 'Offset Tool-path Linking for Pocket Machining', Computer Aided Design, Vol. 34, No.4, pp. 299-308, April 2002 https://doi.org/10.1016/S0010-4485(01)00088-4
  15. Park, S. C., Chung, Y. C. and Choi, B. K., 'Contourparallel Offset Machining without Tool-retractions', Computer Aided Design, Vol. 35, No.9, pp. 841-849, August 2003 https://doi.org/10.1016/S0010-4485(02)00111-2
  16. Held, M., Lukacs, G and Andor, L., 'Pocket Machining based on Contour-parallel Tool Paths Generated by Means of Proximity Maps', Computer Aided Design, Vol. 26, No.3, pp. 189-203, March 1994 https://doi.org/10.1016/0010-4485(94)90042-6
  17. Martin Held, 'Voronoi Diagrams and Offset Curves of Curvilinear Polygons', Computer Aided Design, Vol. 30, No.4, pp. 287-300, April 1998 https://doi.org/10.1016/S0010-4485(97)00071-7
  18. Kim, D.-S., 'Polygon Offsetting Using a Voronoi Diagram and Two Stacks', Computer Aided Design, Vol. 30, No. 14, pp. 1069-1076, December 1998 https://doi.org/10.1016/S0010-4485(98)00063-3
  19. Takashi Maekawa and Nicholas M. Patrikalakis, 'Computation of Singularities and Intersections of Offsets of Planar Curves', Computer Aided Geometric Design, Vol. 10, No.5, pp. 407-429, October 1993 https://doi.org/10.1016/0167-8396(93)90020-4
  20. 박상철, 신하용, 최병규, '점열곡선의 꼬임을 효율적으로 찾는 알고리즘', 한국 CAD/CAM학회논문집, 제4권, 제3호, pp. 190-199, 1999
  21. Bentley, J. L. and Ottmann, T. A., 'Algorithms for Reporting and Counting Geometric Intersections', IEEE Transactions on Computers, 28, pp. 643-647, 1979 https://doi.org/10.1109/TC.1979.1675432
  22. Preparata, F. P. and Shamos, M. I., 'Computational Geometry-An Introduction', Springer Verlag, New York, 1985
  23. Joseph O'Rourke, 'Computational Geometry in C', Cambridge University Press, 1995
  24. M. de Berg, M. van Kreveld, M. Overmars and O. Schwarzkopf, 'Computational Geometry Algorithms and Applications', Springer Verlag, March 1997