A local constraint method for needle insertion modeling and simulation

This paper presents a novel constraint method for dynamic modeling and simulation of needle insertion based on FE framework. Modeling of the interactive events during a needle insertion procedure such as contact, puncture and friction using the finite element method is cumbersome due to the need to continually update the mesh to match the geometry of the discontinuity. Here, we describe a Local Constraint Method that uses outputs generated by the interaction between a needle node and a `contact´ point inside one finite element of the tissue as constraints that affect deformation and the force distribution of the tissue and needle. The constraints are applied at the nodal points of the initial mesh in order to avoid remeshing; and the variations mapped from the needle to points within the tissue region are considered as properties representative of the whole body to ensure accuracy of the simulation. This method can be employed to simulate a dynamic model for different interactions with different material properties. A simulation based on this method to realize the dynamic model of needle insertion is described for validation.