Robotic Endoscope System for Future Application in Minimally Invasive Laser Osteotomy: First Concept Evaluation

Abstract

We are developing a robotic system for future application in minimally invasive laser osteotomy. This paper presents the mechanical system concept as a macro-milli-micro system and focuses on designing and evaluating the milli-system. The millisystem consists of an articulated tendon-driven robotic endoscope with seven rigid links with an outer diameter of 8 mm connected by six discrete rotational joints (±30 • ). These joints can be controlled individually, however, controlling one joint's motion influences all joints located more distally, making joint control an interesting challenge. Controlling each joint as desired will allow positioning the micro-system mounted at the endoscope's tip. The micro-system is itself a robot that will accurately position the laser. The robotic endoscope incorporates a hollow core with a diameter of 4.8 mm that holds a supply channel for the micro-system with the necessary means for actuation and surgical intervention. We demonstrated the functionality of the robotic endoscope in tracking experiments. Despite the joints' mutual influence, the articulated robotic endoscope could be handled successfully and achieved an angular settling error of less than 1 • in the individual joints. The overall robotic system's functionality was successfully demonstrated with a time-synchronized joint movement of the macro-system (serial manipulator) and the robotic endoscope.