Multilayer Needle Insertion Modeling for Robotic Percutaneous Therapy

The modeling of needle insertion into tissues is important for simulation of this procedure and for robotic technologies applied to percutaneous therapy. In this article, we present a first attempt to develop a general force model for the needle insertion throw different tissue layers (skin, fat and muscle) to reach an internal organ (the liver, for instance) with objectives of control, looking for an optimal (less invasive and more accurate) puncture task. The forces are divided into three parts: stiffness, a nonlinear model; friction, a modified Dahl model; and cutting, a constant for a given tissue. Results show that the overall shape of forces presents the main phases of a needle insertion through several tissue layers.