Projecting beam model for robot-assisted flexible needle insertion

Abstract

Needle path steering is one of the most important techniques during robotic-assisted needle insertion.Soft tissue deformation,multi-layer tissue relative sliding and needle deflection can easily make the needle miss the target,which decreases the needle insertion precision.Based on the analysis of needle forces,a projecting beam model was proposed to predict the needle path through laws of needle deflection,with a flexible needle divided into finite segments with quasi-static process during needle insertion and each segment regarded as a projecting beam.An algorithm was then developed to predict the needle path in three-dimensional space.Simulation results show that the proposed model can effectively predict the flexible needle path,which provides a theoretical fundamental for path planning and obstacle avoidance during robot-assisted needle insertion.