在本論文的研究中，我們提出一套腹腔鏡手術模擬系統並且強調對膽囊切除手術中重要程序的訓練。我們提出的系統主要包括了五個部分: 即時變形、逼真的力回饋、快速的碰撞偵測、手術動作、以及逼真的視覺呈現。為了使器官快速且逼真地變形，我們提出了兩種軟組織變形的方法：混合式物理變形模塑與綜合式變形模塑。混合式物理變形模塑可以表現快速而精確的物理變形；綜合式變形模塑則可以逼真地同時表現出器官局部的黏彈性變形以及整體性的移動。為了提供逼真的力回饋，我們使用以彈簧模塑為基礎的力回饋計算。另外，我們提供了四種在膽囊切除手術程序裡常用的手術動作：推、夾、釘膽管鉗、以及剪斷膽管。綜合以上所述，我們成功地發展出一套即時、逼真、且具擴充性的腹腔鏡膽囊切除手術模擬系統。

In this paper, we propose a laparoscopic surgery simulation system which identifies and emphasizes the critical steps in performing the gallbladder removal procedure. The proposed system consists of five components: (i) real-time deformation, (ii) realistic force feedback, (iii) efficient collision detection, (iv) surgical operations, and (v) realistic visualization of the virtual organ models. To realistically deform the soft tissues, we develop two deformation techniques: hybrid physical-based deformation modeling (HPDM) and synthetic deformation modeling (SDM). The proposed HPDM exhibits high speed and physical accurate deformation; the SDM exhibits both local visco-elastic deformation and global motion realistically. To provide a realistic haptic feeling, a force feedback technique based on the mass-spring deformation model is proposed. We also develop four surgical operations necessary for gallbladder removal: pushing, grasping, clamping, and cutting. With these techniques, we successfully develop a real-time, realistic, and expansible laparoscopic surgical simulation for gallbladder removal.

1]Basdogan, C., C.-H. Ho, M. A. Srinivasan, S. D. Small, and S. L. Dawson, “Force interactions in laparoscopic simulations: haptic rendering of soft tissues,” in Proc. of Conf. On Medicine Meets Virtual Reality, San Diego, CA, Jan.19-22, 1998, pp.385-391.
[2]Bechmann, D., “Space deformation models survey,” Computer & Graphics, Vol.18, No.4, pp.571-586, 1994.
[3]Bielser, D., V. A. Maiwald, M. H. Gross, “Interactive Cuts Through 3-dimensional Soft Tissue, ” Technical Report 309, ETH Zürich, Institute of Scientific Computing, Nov. 1998.
[4]Bro-Nielsen, M., “Finite element modeling in surgery simulation,” IEEE Proc., Vol.86, No.3, pp.490-503, 1998.
[5]Chen, Y., Q.-H. Zhu, and K. Arie, “Physically based animation of volumetric objects,” in Proc. IEEE Computer Animation, Philadelphia, Jun.8-10, 1998, pp.154-160.
[6]Coquillart, S., “Extended free-form deformation: a sculpturing tool for 3D geometric modeling,” in Proc. Siggraph’90, Vol.24, No.4, Dallas, TX, Aug.6-10, 1990, pp.187-196.
[7]Cotin, S., H. Delingette, and N. Ayache, Efficient Linear Elastic Models of Soft Tissues for Real-time Surgery Simulation, Technique Report TR-98-3510, Institut National de Recherche en Informatique et en Automatique (INRIA), 1998.
[8]Cover, S. A., N. F. Ezquerra, J. F. O’Brien, R. Rowe, J. Gadacz, and E. Palm, “Interactively deformable models for surgery simulation,” IEEE Computer Graphics & Applications, Vol.13, No.6, pp.68-75, 1993.
[9]Delingette, H., “Toward realistic soft-tissue modeling in medical simulation,” IEEE Proc., Vol.86, No.3, pp.512-523, 1998.
[10]Desbrun, M., P. Schröder, A. Barr, “Interactive animation of structured deformable objects, ” in Graphics Interface ''99, Kingston, Canada, Jun. 1999, pp.1-8.
[11]Gibson, S. F. F. and B. Mirtich, A Survery of Deformable Modeling in Computer Graphics, Technique Report TR-97-19, Mitsubishi Electric Research Laboratory, 1997.
[12]Guan, Z., J. Ling, N. Tao, X. Ping, and T. Rongxi, “Study and application of physics-based deformable curves and surfaces,” Computer & Graphics, Vol.21, No.4, pp.305-313, 1997.
[13]Gudukbay, U., B. Ozguc, and Y. Tokad, “A spring force formulation for elastically deformable models,” Computer & Graphics, Vol.21, No.3, pp.335-346, 1997.
[14]Hsu, W. M., J. F. Hughes, and H. Kaufman, “Direct manipulation of free-form deformations,” in Proc. SIGGRAPH’92, Vol.26, No.2, Chicago, IL, Jul.26-31, 1992, pp.177-184.
[15]Kuhn, C., U. Kuhnapfel, H.-G. Krumm, and B. Neisius, “A ‘virtual reality’ based training system for minimally invasive surgery,” in Proc. Computer Assisted Radiology (CAR’96), Paris, Jun., 1996, pp.764-769.
[16]Kuhnapfel, U. G. and B. Neisius, “CAD-based graphical computer simulation in endoscopic surgery,” Endoscopic Surgery and Allied Technologies, Vol.1, No.2, pp.181-184, 1993.
[17]Kühnapfel, U., H. K. Çakmak, H. Maaß, “3D Modeling for Endoscopic Surgery,“ in Proc. IEEE Symposium on Simulation, Delft University, Delft, NL, Oct. 13, 1999
[18]Louchet, J. , X. Provot, D. Corchemore, “Evolutionary identification of cloth animation models, “ in Eurographics Workshop on Animation and Simulation, Maastricht, Neederland, September 1995, pp.44-54.
[19]Meseure, P. and C. Chaillou, “Deformable body simulation with adaptative subdivision and cuttings,” in Proc. WSCG’97, Plzen, Czech Republic, Feb. 1997, pp. 361-370.
[20]Ng, H. N. and R. L. Grimsdate., “Computer graphics techniques for modeling cloth,” IEEE Computer Graphics & Applications, Vol.16, No.5, pp.28-41, 1996.
[21]Provot, X. , “Collision and self-collision handling in cloth model dedicated to design garments, “ in Eurographics Workshop on Animation and Simulation, Sep. 1997, pp.177-189.
[22]Provot, X. , “Deformation constraints in a mass-spring model to describe rigid cloth behavior,” in Proc. Graphics Interface, Quebec City, Canada, May17-19, 1995, pp.147-154.
[23]Qin, H. and D. Terzopoulos, “Dynamic NURBS swung surfaces for physics-based shape design,” Computer-Aided Design, Vol.27, No.2, pp.111-127, 1995.
[24]Sederberg, T. W. and S. R. Parry, “Free-form deformation of solid geometric models,” in Proc. SIGGRAPH’86, Vol.20, No.4, Dallas, TX, Aug.18-22, 1986, pp.151-160.
[25]Terzopoulos, D. and H. Qin, “Dynamic NURBS with geometric constraints for interactive sculpting,” ACM Trans. on Graphics, Vol.13, No.2, pp.103-136, 1994.
[26]Terzopoulos, D., J. Platt, A. Barr, and K. Fleischer, “Elastically deformable models,” in Proc. SIGGRAPH’87, Vol.21, No.4, Anaheim, CA, Jul.27-31, 1987, pp.205-214.
[27]Volino, P. , M. Courchesne, and N. M. Thalmann, “Versatile and efficient techniques for simulating cloth and other deformable objects,” in Proc. SIGGRAPH’95, volume 29, pp. 13