A passive control framework for a bilateral leader-follower robotic surgical setup imposing RCM and active constraints

We consider the problem of controlling a bilateral leader-follower robotic surgical set-up to allow kinesthetic haptic feedback to the user when the instrument approaches a forbidden area like sensitive organs arteries or veins that should be protected from injuries during surgery. The leader is a haptic device while the follower is a general purpose manipulator holding an elongated tool with an articulated instrument that should be manipulated through an entry port. We propose a control framework that is proved passive, incorporating a target admittance model for the follower that is designed in a way to impose a remote center of motion (RCM) while being subject to repulsive forces generated by properly designed artificial potentials associated with forbidden areas. Simulation and experimental results utilizing a virtual intraoperative environment provided as a point cloud of a kidney and its surrounding vessels characterized as forbidden areas, validate and demonstrate the performance of the proposed control scheme.