Kinematic control of redundant arms based on the virtual incision ports for robotic single-port access surgery

This paper presents a novel kinematic control scheme based on the Virtual Incision Ports (VIPs) for redundancy resolution of redundant robotic arms for single-port access (SPA) surgery. In general, manipulators have 6 DoFs except grippers to be able to reach the desired pose in 3D space. If a surgical robot for SPA surgery has only 6 DoFs, then its workspace could be restricted severely. Therefore most robots including our developed robot consist of more than 6 DoFs with an elbow to maintain triangulation. This means they have a redundancy resolution problem. One of the most popular methods for a redundancy resolution is a pseudo-inverse Jacobian method [1]. In case of robotic SPA surgery, however, this method intrinsically has a high possibility for hurting abdominal organs and muscles or conflicting with other instruments because of the unexpected elbow movements. Our control scheme can decrease the possibility of a collision with them and provide a more flexible working area for surgical tasks by reallocating the VIP. Results presented from simulation and experiment will demonstrate them.