Design Of The Software Platform Of The Minimal Invasive Surgical Training System

At present, Minimal Invasive Surgery (MIS) is widely applied in Medicine. But it takes a long time and high expense for doctor to master this technology. This thesis aims at designing a software platform of the Minimal Invasive Surgery Training System in order to solve this problem. By means of the software development environment VC++6.0, we establish the simulation platform of virtual reality using OpenGL. In this software platform we can implement the geometrical model, physical/compute model, collision detection, real-time deformation, realistic rendering of the model, human-machine interface, and training schemes.Firstly, we design the geometrical models of related human organs and surgery apparatus by 3DS MAX and Pro/E. The triangle-feature face model of human organs and surgery apparatus are rebuilt in the circumstance of OpenGL through compiling the interface programs between the training system and the modeling software such as 3DS MAX and Pro/E.Secondly, i do a deep research in collision detection problem between flexible objects (models of human organ models) and rigid objects (models of surgery apparatus). I described and analyzed the flow chart of the collision detection algorithm of hierarchical bounding volume and intersection testing method of the basic geometrical elements. This paper provides an effective algorithm based on AABB bounding volume hierarchy to realize the real-time collision detection in complex environment of this virtual surgery, and resolves the problems about intersection tests between bounding volumes, updating bounding volumes after rotation and updating bounding volume hierarchy after deformation.And then, the human organ tissue is simplified to linear model. The human organ is discrete to a mass-spring-damper system, so we can use stiffness coefficient, damping coefficient, and mass point density to represent the characters of the human organ. The topology of the tissue is described by the adjacent tables, and the dynamical equations can be constructed based on the data stored in the adjacent tables. The Euler method is used to integrate the equations of deformation and feed-back force.Finally, we realize functions of human-machine interface, realistic rendering of the model and communication with machine by programming on the platform developed by VC and OpenGL. Since all the training schemes are carried out, the physician can...