Manipulation of a Whole Surgical Tool Within Safe Regions Utilizing Barrier Artificial Potentials

Abstract

Active constraint enforcement in robotic-assisted surgery is critical for reducing the intra-operative risk of unintentionally damaging sensitive tissues by the surgical instrument. This work considers surgical instruments which can be circumscribed by a geometric capsule and forbidden regions which can be approximated by point clouds in order to produce a repulsive wrench by the control action to guarantee manipulation within safe regions. This work details the control scheme which is based on barrier artificial potentials when considering the whole tool extending our previous results on the tool point. A proof of the control system’s passivity and non constraint violation is provided together with experimental results using a 7-dof KUKA LWR4+ manipulator as a master device in a virtual surgical scene in order to demonstrate the effectiveness of the proposed scheme.