Modeling of lower intestinal tract for colonoscopy simulator

Abstract

This thesis presents a novel modeling technique suitable for colonoscopy training simulator called the centerline-based modeling. The colon is regarded as serially connected cylinders along the medial axis. The Timoshenko beam theory is applied to the centerline of colon extracted from a medical image for global deformation. The stiffness matrix of colon is formulated using the finite element method and appropriate numerical method is verified for dynamic simulation. Also, colonoscope model has been assumed to consist of rigid elements connected with torsional damper and spring since the change of the length is a negligible quantity. Simple and fast collision detection and response algorithm are presented in order for interaction between colon and colonoscope. The proposed method is concerned with modeling technique suitable for global bending behavior of colon for colonoscopy training simulator. Further, this method can be applied to similar medical training simulators such as gastroscopy and urethroscopy.