Design and development of portable tool positioning robot for telesurgery

The objective of this research is the synthesis, design, and development of a next generation surgical robotic system to increase assimilation of surgical robots in minimally invasive surgery. This portable robotic system is constructed for multipurpose use, such as guiding surgical tools, positioning laparoscopic cameras, and cooperating with miniature in vivo robots. A compact, portable robot has been developed using a spherical bevel-geared mechanism to achieve the necessary workspace for minimally invasive surgery in four degrees of freedom. Kinematics have been developed as a foundation for workspace analysis and intuitive motion control. Further, inverse dynamic modeling has been presented for advanced dynamic control system implementation. An optimal design methodology for spherical serial mechanisms has been presented based on genetic algorithms. Multiple criteria (workspace, manipulability, and size) with changeable priorities are linearly combined in one objective function for different desirable performance emphases. A new metric of workspace quality, consistent manipulability, has been defined to involve both the global manipulability and the uniformity of manipulability over the workspace. The optimization results of the presented robot demonstrate the effectiveness of the proposed methodology. The flexible and adaptable methodology also provides a general optimization approach for robot linkage synthesis. The derived kinematics are integrated in control software for intuitive master-slave control. Use of the robotic system for camera guidance and for cooperation with miniature in vivo robots in porcine models indicates that the robot can provide the surgeon with a stable and remotely adjustable platform for holding and positioning of tools for minimally invasive surgery. Compact robotic systems based on this technology could replace the large systems in current use, potentially increasing the impact of robots on medical care