Study of methods and techniques for trocar insertion simulation

A critical first step for most minimally invasive surgical procedures is trocar insertion. What makes this procedure difficult to learn and master is that it is carried out with no or limited visual feedback of the underlying organs at the puncture site. Most injuries incurred by the patient are directly correlated to the use of excessive force by the surgeon. The research work in this thesis is focused on simulating the trocar insertion procedure to provide real time simulation for techniques used in training surgeons for performing this procedure. Our methodology uses a six-degree-of-freedom haptic simulator for trocar insertion task. Our approach uses data collected from in-vivo experiments and mechanical testing of synthetic materials for modeling a force profile. This data is then fit into a mathematical model which is used for haptically enabled trocar insertion simulation with a force feedback device. The haptic deformation algorithm uses differential haptic rendering methodology. Also this research work investigated FEM based procedure for accurately predicting the displacement pattern and stress distribution for trocar insertion. Biological tissue modeling has been discussed at length in the thesis based on existing multimechanism constitutive model. A haptic based simulator was developed for surgeon training. A user study is planned to evaluate this system in future.