A New Method to Render Virtual Walls for Haptic Systems: Tracking Wall. Application to Needle Insertion Simulation

For medical training, the use of haptic systems is a way to improve skills of novices, due to their capabilities to reproduce the natural gestures or replicate different environments. A simulator based on a haptic interface allows to reproduce the feeling of inserting a needle and render the different stiffness tissues while a needle is inserted. The majority of needle insertion simulators make use of prosthesis or limbs which limits the training procedures. Some simulators offer more realistic behavior using control laws based on active walls. However, problems occur with the speed estimation and the damping factor. To overcome this, an algorithm which can be used in a haptic simulator for the intraarticular punction procedure was developed. This algorithm allows rendering different tissues stiffness while a needle penetrates it avoiding speed estimation problems and rumbling phenomena caused by high damping factors.