Comparison And Optimization For Kinematic Performance Of Various Continuum Surgical Manipulators

Less invasive surgical paradigms, such as single port access surgery and natural orifice translu-menal endoscopic surgery procedures, potentially have many advantages over the traditional minimally invasive surgeries, such as fewer complications, less trauma, better cosmesis and faster recovery.In order to meet the demands of providing miniature yet versatile surgical instruments, robotic-assistance has been introduced into the single port access surgery and natural orifice endoscopic surgery procedures. Among the existing designs, a few designs using continuum mechanisms demonstrate promising results in further miniaturization while maintaining desired kinematic dexterity. In order to better reveal the potentials of continuum surgical manipulators, this master research investigates kinematic performance of several continuum manipulators through comparisons and optimizations. Three different continuum surgical manipulators from the existing designs are chosen for comparison. After the presentation of their kinematics, they are compared in terms of their reachable translational workspace and distal dexterity within the functional workspace at selected points. The comparison results have shown the strengths and limitations of different continuum manipulators. Optimizations are conducted then to find the optimal structural parameters of these continuum manipulators with a consistent optimization target. Then the comparison of their kinematic performances is carried out again under their corresponding optimal structural parameters. The results obtained in this thesis can provide design references for future developments of robotic surgical systems with continuum surgical manipulators.One endoscopic continuum robot prototype is presented in this thesis to show the capability of continuum surgical manipulators in realization of intervention miniaturization and dexterous kinematic performance. The prototype has an outer diameter of12mm in its folded endoscope configuration. It can be easily inserted through a patient’s esophagus and deployed into the stomach, where it can be unfolded into the working configuration. By fulfilling the knot tying surgical task validated by a simulation and operated in a master-slave mode, the dexterity of the continuum manipulator is successfully demonstrated.