Deformation of Soft Tissue and Force Feedback Using the Smoothed Particle Hydrodynamics

Abstract

We study the deformation and haptic feedback of soft tissue in virtual surgery based on a liver model by using a force feedback device named PHANTOM OMNI developed by SensAble Company in USA. Although a significant amount of research efforts have been dedicated to simulating the behaviors of soft tissue and implementing force feedback, it is still a challenging problem. This paper introduces a kind of meshfree method for deformation simulation of soft tissue and force computation based on viscoelastic mechanical model and smoothed particle hydrodynamics (SPH). Firstly, viscoelastic model can present the mechanical characteristics of soft tissue which greatly promotes the realism. Secondly, SPH has features of meshless technique and self-adaption, which supply higher precision than methods based on meshes for force feedback computation. Finally, a SPH method based on dynamic interaction area is proposed to improve the real time performance of simulation. The results reveal that SPH methodology is suitable for simulating soft tissue deformation and force feedback calculation, and SPH based on dynamic local interaction area has a higher computational efficiency significantly compared with usual SPH. Our algorithm has a bright prospect in the area of virtual surgery.

A review of virtual cutting methods and technology in deformable objects

“…In addition, it is also an effective method to reduce the cost of calculation by using the model reduction method to reduce the dimension of the model rationally on the basis of ensuring effective precision . In addition, some meshing methods, mesh optimization methods, and some meshless methods that are not used or applied in fields other than surgical simulation are also of concern.…”

Virtual reality simulation of robotic transsphenoidal brain tumor resection: Evaluating dynamic motion scaling in a master‐slave system

“…The finite element method (FEM) has been widely applied in many virtual surgical simulations. FEMs are based on continuum mechanics, with a strong mathematical foundation and physical validity; however, because of the high computational load, the real‐time response cannot be ensured, and changes in the mesh topology become prohibitive when a precomputed response is used to speed up the solution …”

“…FEMs are based on continuum mechanics, with a strong mathematical foundation and physical validity [27][28][29] ; however, because of the high computational load, the real-time response cannot be ensured, and changes in the mesh topology become prohibitive when a precomputed response is used to speed up the solution. 30 In our work, we proposed to use position-based dynamics, 31 in which the shape of the anatomical structures is discretised into particles, each one containing information about its position, mass, and velocity. The properties of the elastic material are approximated by using distance constraints C that contain information about the rest length l o (starting length of any spring in rest position) and a stiffness factor μ 32 ( Figure 6).…”

Meshfree and Particle Methods in Biomechanics: Prospects and Challenges

“…In their study, they also established a unified formulation of fluid-structure interaction based on particle methods. For the sake of improved accuracy, better real-time, stability and ease in performing virtual real-time surgery simulation, several other modified or hybrid meshfree and particle methods have been proposed in the literature [87][88][89]. The following boundary conditions and initial condition are applied to the four boundaries, as shown in Fig.…”