A preliminary study of suture simulation in virtual surgery

A suture simulation system is developed. Using a Phantom desktop haptic device, user can insert a virtual needle into a deformable object and pull a virtual suture attached to the needle through the object. The object can deform under the interaction of both the needle and the suture. The suture uses rigid link model and FTL(Follow the Leader) deformation algorithm. Tensor-mass deformation method based on linear elasticity is used for the deformable object. Sliding constraints are formed when the suture is being pulled through the object. At each sliding constraint point, internal tension force of the suture is applied to the object, while the deformation of the object affects the position of the constraint point conversely. Smooth movement of the suture through sliding constraint point is achieved by combining two methods: Adjusting lengths of rigid links on both sides of the constraint and increment of attached suture vertex index. Suture simulation on a simple deformable object with cutting wound is performed and the results and future improvements are discussed.