Integrating viscoelastic mass spring dampers into position-based dynamics to simulate soft tissue deformation in real time

We propose a novel method to simulate soft tissue deformation for virtual surgery applications. The method considers the mechanical properties of soft tissue, such as its viscoelasticity, nonlinearity, and incompressibility; its speed, stability, and accuracy also meet the requirements for a surgery simulator. Modifying the traditional equation for mass spring dampers introduces nonlinearity and viscoelasticity into the calculation of elastic force. Then, the elastic force is used in the constraint projection step for naturally reducing constraint potential. The node position is enforced by the combined spring force and constraint conservative force through Newton’s second law. We conduct a comparison study of conventional mass spring dampers and position based dynamics (PBD) for our new integrating method. Our approach enables stable, fast, and large step simulation by freely controlling visual effects based on nonlinearity, viscoelasticity and incompressibility. We implement a laparos...