組織工程支架提供細胞貼附和生長環境，結合所需的調控因子和生物反應器可以誘使細胞分化與組織再生，而支架的三維結構會影響細胞的遷移、培養液的流動，所以支架結構設計與製作方式是否良好對細胞在支架內部的培養成效有相當的影響。支架的三維結構可以藉由電腦輔助設計出理想的支架模型或從電腦斷層掃瞄影像重建並擷取所需的區域。
本研究主要在發展一套製作支架的軟體，包含支架與支撐路徑規劃及加工機器控制介面，並針對路徑線段端點懸空的問題提出解決方案，以使支架製作品質更趨完善。在支架路徑規劃方面，就模型切層輪廓與路徑線段做交集運算，求出支架路徑線段端點，再判斷支架路徑線段端點是否懸空。假如端點懸空，則須把端點投影到下一層切面上，並從下一層支架路徑線段中找離端點最近的點替代之，以避免材料的累積。又為了節省模型製作的時間，路徑線段端點會被依序連結幾個連續路徑。在另一方面，任一層的支撐區域面積是將該層以上的支架材料區域聯集與該層的支架面積輪廓做差集求出，而支撐路徑線段的端點位置是由該層以上的各層支架路徑線段端點投影在該層支撐區域上，再經分類後求出。最後再判斷支撐跟支架路徑線段是否會發生碰撞，假如發生碰撞需修改支撐路徑線段端點。由耳朵模型的模擬實驗中得知本研究的方法確實能夠改善支架的製作品質。

The scaffold for tissue engineering provides cell adhesion and growing environment. Combining regulatory factor and bio-reactor can induce cell differentiation and tissue regeneration. The three dimensional structure of the scaffold affects cell migration and the flow of medium. Therefore the structure design and fabrication method of scaffolds have great influence for cell culture inside the scaffold. The structure of the scaffold can be designed by applying computer-aided design or generated from CT image model.
This research is to develop a software program to fabricate scaffold models, including the planning of scaffold and supporter path and the control interface of the processing machine, and to solve suspending problems of path points of scaffolds so that the quality of scaffolds can be improved. In the path planning of scaffolds, the path points are derived by finding the intersection points of the slice contour and paths and then judged if they are suspended in the air. If any path point is suspended, it will be replaced by the path point on the next lower layer, which is closest to the projection of the path point on the next lower layer, so that material will not accumulate. Also, the path pints will be connected sequentially to form several continuous paths to save fabrication time. On the other hand, the supporter area of each layer is derived by finding the difference between its scaffold area and the union of the scaffold areas of all layers above this layer. The path points of the supporter area are determined by analyzing and categorizing those of the scaffold areas above this layer. Finally, the supporter paths will be judged whether they are collided with the scaffold paths. If a collision happens, the position of the supporter path point will be modified. The path planning simulation experiment using an ear model shows that the proposed method is definitely able to improve the production quality of scaffolds.

[1] Kai, C. C. and Fai, L. K. 著，快速成型，黃台生譯，六合出版社，台北，民國八十七年.
[2] 楊志明主編，組織工程，九州圖書，台北市，民國九十四年.
[3] Chalkof, E. L., Biomaterials that imitate cell microenvironments, Chemtech, Vol. 26(8), pp. 17, 1996.
[4] Ratner, B. D., Hoffman, A. S., and Schoen, F. J., An introduction to materials in medicine, pp. 64-72, Academic Press, 1996.
[5] Ang, T. H., Sultana, F. S. A., Humacher, D. W., et. al., “Fabrication of 3D
chitosan–hydroxyapatite scaffolds using a robotic dispensing system”, Materials Science and Engineering C, Vol. 20(1-2), pp. 35-42, 2002.
[6] 黃學惠, “骨細胞支架之電腦輔助設計與製造,” 國立成功大學醫學工程研究所碩士論文, 民94.
[7] 呂桓綜, “組織工程精密支架之製造”, 國立中央大學機械工程研究所碩士論文, 民91.
[8] 林峰輝、白育綸編修，及俞耀庭主編，生物醫用材料，新文京開發，台北縣，民國九十三年.
[9] Yang, S., Leong, K. F., Du, Z., et. al., “The design of scaffolds for use in tissue engineering. Part I. Traditional Factors”, Tissue Engineering, Volume 7(6), pp. 679-689. 2001.
[10] Jacobs, P. F., Fundamentals of stereolithography, Society of Manufacturing Engineers, Dearborn, MI, pp. 11-18, 1992.
[11] Kobe, G.., Cubital''s unknown solider, Automotive Industries, pp. 54-55, August, 1992.
[12] Burns, M, Improving productivity in manufacturing, PTR Prentice Hall, 1993.
[13] Kruth, J.P., “Material increase manufacturing by rapid prototyping techniques”, Ann CIRP, Vol. 42(2), pp. 603-614, 1991.
[14] Crump, S., “The extrusion of fused deposition modeling”, Proceedings of the Third International Conference Rapid Prototyping, pp. 91-102, 1992.
[15] 介紹3D系統的多頭噴射造型系統 http://www.3dsystems.com/
[16] Deckard, C. R. and Beaman, J. J., “Recent advances in selective laser sintering”,
In Proceedings of the Fourteenth Conference on Production Research and Technology, pp. 447-452, 1987.
[17] Uziel, Y., “Art to Part in 10 Days”, Machine Design, pp. 56-60, August, 10, 1995.
[18] Greulich, M., Pintat, T., and Pintat, T., “Functional prototypes via multiphase jet
solidification”, Rapid Prototyping Journal, Vol. 1(1), pp. 20-25, 1995.
[19] Richardson, K. E, “The production of wax models by the ballistic particle manufacturing process”, Proceedings of the Second International Conference on Rapid Prototyping, pp.15-22, 1991.
[20] Sachs, E., Cima, M., Williams, P., et. al., “Rapid tooling and prototypes directly from a CAD model”, Journal of Engineering for Industry, Vol. 114, pp. 481-488, 1992.
[21] Rock, S. J. and Wozny, M. J., “Generating topological information from a bucket of facets”, Proceedings of Solid Freeform Fabrication Symposium, pp. 251-259, Austin, TX, 1991.
[22] Guduri, S., Crawford, R. H., and Beaman, J. J., “Direct generation of Contour files from constructive solid geometry representations”, Proceedings of Solid Freeform Fabrication Symposium, pp. 291-302, Austin, TX, 1993.
[23] Dolenc, A. and M?kel?, I., “Slicing procedures for layered manufacturing techniques”, Computer-Aided-Design, Vol. 26, p.19-26, 1994.
[24] Sabourin, E., Houser, S. A., and Bohn, F. H., “Adaptive slicing using stepwise uniform refinement”, Rapid Prototyping Journal, Vol. 2(4), pp. 20-26,1996.
[25] Sabourin, E., Houser, S. A., and Bohn, F. H., “ Accurate exterior, fast interior layered manufacturing”, Rapid Prototyping Journal, Vol. 3(2), pp. 44-52,1997.
[26] Tyberg, J. and Bohn, J.H., “Local adaptive slicing”, Rapid Prototyping Journal, Vol. 4(3),pp. 118-127, 1998.
[27] Suh, Y. and Wozny, M. J., “Adaptive slicing of solid freeform fabrication processes”, Proceedings of Solid Freefoerm Fabrication Symposium, Austin, Tx, 1994.
[28] Hong, S. B. and Kawn, H. L., “Determination of Optimal Build Direction in Rapid Pototyping with Variable Slicing,” The International Journal of Advanced Manufacturing Technology, Vol. 28(3), pp. 69-80, 2006.
[29] Kulkarni, P., Marsan, A., and Dutta, D., “A Review of Process Planning Technologies in Layered Manufacturing,” Rapid Prototyping Journal, Vol. 6(1), pp. 18-35, 2002.
[30] 陳彥霖, “組織工程用三維支架之電腦輔助製程設計,” 國立中央大學機械工程研究所碩士論文, 民96.
[31] Masood, S. H. and Rattanawong, W., “A Generic Part Orientation System Based on Volumetric Error in Rapid Prototyping,” The International Journal of Advanced Manufacturing Technology, Vol. 19, No. 3, pp. 209-216, 2002.
[32] Wang, F., Shor, L., and Darling, A., et. al., “Precision Extruding Deposition and Characterization of Cellular Poly- -Caprolactone Tissue Scaffold”, Rapid Prototyping Journal, Vol. 10, pp. 42-49, 2004.
[33] 黃仁波, “以冷凍式快速原型法製作組織工程支架,” 國立中央大學機械工程研究所碩士論文, 民94.