Passive Bilateral Surgical Teleoperation With RCM and Spatial Constraints in the Presence of Time Delays

The primary issue in bilateral teleportation setups is the existence of communication delays, which can destabilize the system. We are addressing this challenge in the case of a bilateral leader–follower surgical setup, where the surgeon uses a haptic device as the leader robot to manipulate the surgical instrument held by a general-purpose manipulator, the follower robot. The follower robot is equipped with an elongated tool that through a small incision passes inside the patient's body, where sensitive structures may exist. These structures may include organs, arteries, or veins that require protection during surgery. To address this challenge, we propose a bilateral control framework that is proven to maintain passivity, ensure bounded tracking errors between the leader and follower robots, and impose remote center of motion and spatial constraints related with the sensitive structures, all in the presence of constant and variable communication delays. Experimental results in a virtual intraoperative environment, using a point cloud of a kidney and its surrounding vessels, demonstrate the effectiveness of our control scheme under various communication delay scenarios.