International Journal of CAD/CAM

Society for Computational Design and Engineering (한국CDE학회)
권호 표지

Direct Slicing with Optimum Number of Contour Points

  • Gupta Tanay (Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur, India) ;
  • Chandila Parveen Kumar (Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur, India) ;
  • Tripathi Vyomkesh (Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur, India) ;
  • Choudhury Asimava Roy (Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur, India)
  • Published : 2004.12.01
Download PDF
⟨ Previous Next ⟩

Abstract

In this work, a rational procedure has been formulated for the selection of points approximating slice contours cut in LOM (Laminated Object manufacturing) with first order approximation. It is suggested that the number of points representing a slice contour can be 'minimised' or 'optmised' by equating the horizontal chordal deviation (HCD) to the user-defined surface form tolerance. It has been shown that such optimization leads to substantial reduction in slice height calculations and NC codes file size for cutting out the slices. Due to optimization, the number of contour points varies from layer to layer, so that points on successive layer contours have to be matched by four sided ruled surface patches and triangular patches. The technological problems associated with the cutting out of triangular patches have been addressed. A robust algorithm has been developed for the determination of slice height for optimum and arbitrary numbers of contour points with different strategies for error calculations. It has been shown that optimisation may even lead to detection and appropriate representation of elusive surface features. An index of optimisation has been defined and calculations of the same have been tabulated.

Keywords

References

  1. Hope, R.L., Jacobs, P.A. and Roth, R.N. (1997), 'Rapid Prototyping with sloping surfaces', Rapid Prototyping Journal, 3(1), 12-19
  2. Hope, R.L., Jacobs, P.A. and Roth, R.N. (1997), 'Adaptive Slicing with sloping layer surfaces', Rapid Prototyping Journal, 3(3), 89-98
  3. de Jager, P.J, Brock, J.J. and Vergeest, J.S.M. (1997), 'Comparison between zero and first order approximation algorithms for layered manufacturing', Rapid Prototyping Journal, 3(Issue 3), 144-149
  4. Yong-Tai Im and Daniel F Walczyk (2002), 'Development of a Computer-Aided Manufacturing System for Profiled edge lamination Tooling', Transactions of the ASME, Journal of Manufacturing Science and Engineering, Vol. 124, Aug, 754-761
  5. Kumar, M. and Roy Choudhury A (2002), 'Adaptive Slicing with Cubic Patch Approximation', Rapid Prototyping Journal, 8(4), 224-232
  6. Banerjee Ashis Gopal, Kumar Aloke, Shankar Tejavath and Roy Choudhury Asimava, (2003), Adaptive Slicing with Curvature Considerations', International Journal of CAD-CAM, 3(1), 31-40
  7. Kumar Aloke, Banerjee Ashis Gopal, Paul S and Roy Choudhury A (2003), Maximization of Slice Height with Uniformity in Surface Roughness in Direct Slicing of Free Form Surfaces, Proceedings of the Institutions of Mechanical Engineers (IMECHE), Vol. 217, Part B, Journal of Engineering Manufacture, pp. 765-777
  8. Chen, Y.H. and Song, Y (2001), 'The Development of a Layer-based Machining System', Computer Aided Design, 33(4), 331-342
  9. Suh, Y. and Wozny, M.J. (1994), 'Adaptive slicing of solid freeform fabrication processes', Proceedings of the solid freeform Fabrication Symposium, University of Texas at Austin, Austin, TX, pp. 404-411
  10. Rogers, D.E and Adams, J.A. (1990), Mathematical Elements For Computer Graphics, McGraw-HilI, New York, N.Y.
  11. Choi, B.K. (1991), Surface Modelling for CAD-CAM, Elsevier, Amsterdam