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Slice overlap-detection algorithm for process planning in multiple-material stereolithography


Recently, a multiple-material stereolithography (MMSL) system was introduced, which included the novel feature of stacking different photocurable resins to produce a multiple-material part. This process is capable of fabricating intricately detailed parts with smooth surface finish and internal structures of various colors. However, the MMSL system requires a washing process when switching materials, and this additional step increases the fabrication time and also introduces deformations in the build structure as registration errors accumulate. Consequently, reducing the number of material changeovers in this process is a priority, and the minimum number of changeovers is imposed in part by the sweep interference between layers of different materials. Fortunately, the use of low-viscosity resins permits possible fabrication without sweeping. As a result, multiple layers of one material can be continuously built without changing resins, and subsequently, a different low-viscosity material can be added without resulting in sweep obstruction with the original layers. In this paper, a stacking simulation, which determines the maximum number of layers possible to be continuously built between material changeovers, is described. This paper presents a novel interference-detection algorithm, which identifies interference by inspecting the overlap between loop segments. In addition, the algorithm successfully manages the triangulation errors that occur at a curved surface when two materials are adjacent within a layer. Finally, several practical examples are shown to verify the algorithm and provide compelling evidence that the proposed algorithm is effective and applicable in MMSL.

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  1. Huang T, Mason MS, Zhao X, Hilmas GE, Leu MC (2009) Aqueous-based freeze-form extrusion fabrication of alumina components. Rapid Prototyping J 15(2):88–95

    Article  Google Scholar 

  2. Zarringhalam H, Majewski C, Hopkinson N (2009) Degree of particle melt in Nylon-12 selective laser sintered parts. Rapid Prototyping J 15(2):126–132

    Article  Google Scholar 

  3. Sangermano M, Ortiz RA, Urbina BAP, Duarte LB, Valdez AEG, Santos RG (2008) Synthesis of an epoxy functionalized spiroorthocarbonate used as low shrinkage additive in cationic UV curing of an epoxy resin. Eur Polymer J 44(4):1046–1052

    Article  Google Scholar 

  4. Sandoval FH, Wicker RB (2006) Functionalizing stereolithography resigns: effects of dispersed multi-walled carbon nanotubes on physical properties. Rapid Prototyping J 12(5):292–303

    Article  Google Scholar 

  5. Chung C-M, Kim J-G, Kim M-S, Kim K-M, Kim K-N (2002) Development of a new photocurable composite resin with reduced curing shrinkage. Dent Mater 18(2):174–178

    Article  Google Scholar 

  6. Nam S, Khalil J, Sun W (2005) Multi-nozzle deposition for construction of 3D biopolymer tissue scaffolds. Rapid Prototyping J 11(1):9–17

    Article  Google Scholar 

  7. Jafari MA, Han W, Mohammadi F, Safari A, Danforth SG, Langrana N (2000) A novel system for fused deposition of advanced multiple ceramics. Rapid Prototyping J 6(3):161–174

    Article  Google Scholar 

  8. Jackson B, Wood K, Beaman JJ (2000) Discrete multi-material selective laser sintering (M 2 SLS): development for an application in complex sand casting core arrays. Proc Solid Freeform Fabr 2000:176–182

    Google Scholar 

  9. Santosa J, Jing D, Das S (2002) Experimental and numerical study on the flow of fine powders from small-scale hoppers applied to SLS multi-material deposition—part I. Proc Solid Freeform Fabr 2002:620–627

    Google Scholar 

  10. Liew CL, Leong KF, Chua CK, Du Z (2001) Dual material rapid prototyping techniques for the development of biomedical devices. Part I: space creation. Int J Adv Manuf Technol 18(10):717–723

    Article  Google Scholar 

  11. Liew CL, Leong KF, Chua CK, Du Z (2002) Dual material rapid prototyping techniques for the development of biomedical devices. Part II: secondary powder deposition. Int J Adv Manuf Technol 19(9):679–687

    Article  Google Scholar 

  12. Ram GD, Janaki RC, Yang Y, Stucker BE (2007) Use of ultrasonic consolidation for fabrication of multi-material structures. Rapid Prototyping J 13(4):226–235

    Article  Google Scholar 

  13. Bondi SN, Johnson RW, Elkhatib T, Gillespie J, Mi J, Lackey WJ (2003) Multi-material and advanced geometry deposition via laser chemical vapor deposition. Rapid Prototyping J 9(1):14–18

    Article  Google Scholar 

  14. Jacobs PF (1992) Rapid prototyping & manufacturing: fundamentals of stereolithography. Society of Manufacturing Engineers, pp 153-220

  15. Byun HS, Lee KH (2005) A decision support system for the selection of a rapid prototyping process using the modified TOPSIS method. Int J Adv Manuf Technol 26:1338–1347

    Article  Google Scholar 

  16. Masood SH, Rattanawong W (2002) A generic part orientation system based on volumetric error in rapid prototyping. Int J Adv Manuf Technol 19:209–216

    Google Scholar 

  17. Liang JS, Lin AC (2004) Multi-nozzle spraying path generation directly from scanned data for rapid prototyping. Internal Journal of Advanced Manufacturing Technology, Vol. 23, pp 553-565

    Google Scholar 

  18. Wicker RB, Medina F, Elkins CJ (2004) Multiple material micro-fabrication: extending stereolithography to tissue engineering and other novel application. Proceedings of 15th Annual Solid Freeform fabrication Symposium, Austin, TX pp 754-764

  19. Arcaute K, Zuverza N, Mann B, Wicker R (2007) Multi-material stereolithography: spatially-controlled bioactive poly(ethylene glycol) scaffolds for tissue engineering. Proceedings of 18th Annual Solid Freeform Fabrication Symposium, Austin, TX, pp 458-69

  20. Inamdar A, Medina F, Magana M, Grajeda Y, Wicker RB (2006) Development of an automated multiple material stereolithography machine. Proceedings of 17th Annual Solid Freeform fabrication Symposium, Austin, TX, pp 624-635

  21. Varadan VK, Jiang X, Varadan VV (2001) Microstereolithography and other fabrication techniques for 3D MEMS. Wiley, West Sussex

    Google Scholar 

  22. Tan W, Gibson I (2005) Numerical study on the recoating process in microstereolithography. Proceedings of 16th Annual Solid Freeform Fabrication Symposium, Austin, TX, pp 458-69

  23. Kim H, Choi J-W, Wicker RB (2008) A rule based scheduling and process planning method for a multi-material stereolithography system. 19th International Solid Freeform fabrication Symposium, pp 26-27

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Correspondence to Ho-Chan Kim.

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Kim, HC., Choi, JW., MacDonald, E. et al. Slice overlap-detection algorithm for process planning in multiple-material stereolithography. Int J Adv Manuf Technol 46, 1161–1170 (2010).

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  • Multiple material
  • Rapid prototyping
  • Stereolithography
  • Process planning
  • Slice
  • Algorithm