An improved mass-spring model for soft tissue deformation with haptic feedback

Modelling of soft tissue deformation is important to many modern applications of technology to medicine such as surgery simulation. This paper presents a new method for modelling soft tissue deformations by incorporating a force propagation mechanism in the traditional mass-spring model. This method automatically adjusts the number of layers involved in the deformation process to control the process of force propagation and the behaviours of soft tissue deformation. It avoids the laborious formulation of the stiffness matrices involved in the traditional mass-spring model, provides more realistic behaviours and faster responses for soft tissue deformation. A haptic device has been integrated to simulate soft tissue deformation with force feedback. Both physical and simulation experiments are performed to evaluate the ability of the proposed deformable model to reproduce the properties of real soft tissues. Examples are presented to demonstrate the efficacy of the proposed model.