A teleoperated platform for transanal single-port surgery: Ergonomics and workspace aspects

We present a new teleoperation setup for minimally invasive single-port surgery through natural orifices. The system consists of an intra-corporal parallel slave robot with two instrument arms and a corresponding master interface with four degrees of freedom and grasping. The master interface mimicks the slave robot kinematics to prevent non-achievable movements. With a workspace of ø 60 mm × 85 mm, interaction forces of up to 5 N and mean speeds of up to 327 mm/s the robot is designed to perform a rectum resection intervention, an operation hardly possible with conventional laparoscopic instruments. In this work, we address several ergonomic aspects of the setup, including surgeon's pose, movement scaling, visual feedback, and haptic feedback. Two experiments were performed to investigate the accuracy and dexterity of the robotic system compared to conventional single-port systems. We found a significant decrease of errors in a point-and-touch-task when using the robot, but no effect on the duration of the task. Surgeons were able to perform suturing and knotting tasks as well as a gall bladder extraction in a porcine model with the robot in an hands on experiment. These experiments showed a good intuitivity and a high instrument control precision as described by the participants