A hybrid physical deformation modeling for laparoscopic surgery simulation

A hybrid physical-based deformation modeling (HPDM) technique for the authors' laparoscopic surgery simulation system is proposed. The proposed technique consists of three components: (i) approximate continuum free-form deformation modeling, (ii) efficient collision detection for non-rigid objects, and (iii) mass-spring modeling for force feedback implementation. Three physical-based deformation modeling techniques which have been applied to surgical simulation are the mass-spring model, the approximate continuum model, and the finite element model. All these models have disadvantages of less realism or are time consuming. Here, the authors propose the HPDM to achieve the realistic deformation of organs in a computationally efficient framework. The proposed HPDM exhibits more physical accuracy and realism than the mass-spring modeling exhibits and has the advantages of more efficient computation, allowing topology change and satisfying arbitrary geometric meshes, compared to the approximate continuum model. Moreover, the friction of the non-perfect force-feedback instrument is compensated by software.