Experimental study on restricting the robotic end-effector inside a lesion for safe telesurgery

Abstract

Introduction: Using an endoscopic telesurgical robot system (ETSRS), the authors propose a strategy for improving the safety of telesurgery by restricting the movement of an end-effector within a lesion. The strategy is validated by phantom model experiments. Material and methods: The method focused on generation of force feedback and restriction of robotic end-effector movement of ETSRS based on a virtual wall. Collision detection and case classification procedures were used to determine whether the generation of force feedback or restricting the end-effector's movement was continued. The method was implemented in ETSRS and tested using a brain and tofu phantom. Results: Force feedback was well generated proportional to a linear combination of the insertion depth and the velocity of the end-effector of the ETSRS from the surface of the predefined virtual wall. The movement of the end-effector was well limited inside the virtual wall by the method. The virtual wall update was sufficiently fast to check the current surgical situation. The control rate of the entire system was >30 fps so that the method showed acceptable performance in phantom experiments. Conclusion: The results show that the strategy allows for well controlled robotic end-effectors inside a predefined virtual wall by the robot itself and an operator through the signal and force feedback.