A Nonlinear Viscoelastic Tensor-Mass Visual Model for Surgery Simulation

The linear elastic models of soft tissue are widely used in virtual-reality-based surgery simulation due to their computational efficiency; however, it is well known that these models are only a coarse approximation of the real biological soft tissue. To achieve realistic simulation, the deformable model should incorporate many other tissue properties such as nonlinearity, anisotropy, and viscoelasticity. Among these properties, viscoelasticity is a very important one, and it directly determines the behaviors of the tissue when it is cut, deformed, or torn. In this paper, we proposed to incorporate the property of viscoelasticity into the visual model of soft tissue. One significant advantage of the developed model is its fast computation. Experiments show that the incorporation of nonlinear viscoelasticity makes the simulated tissue look much more realistic than other models, whereas the computation time is increased by only approximately 5% compared with models without the consideration of viscoelasticity.