Mechanical & Materials Engineering, Department of


Date of this Version

Summer 8-2011


A Thesis Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Mechanical Engineering, Under the Supervision of Professor Carl A. Nelson. Lincoln, Nebraska: August, 2011

Copyright 2011 Wei Jian Chin


Natural Orifice Translumenal Endoscopic Surgery (NOTES) is a fairly recent surgical approach that eliminates the need for external incisions on the patient. NOTES takes the minimally invasive surgery paradigm a step further by using a natural orifice as the pathway to transport surgical tools to the surgical site and completely eliminating the need for even the smallest incision on the skin. Although the concept of NOTES has been in existence for the past decade, technological deficiencies prevent it from being widely accepted in human surgeries. A novel multifunctional robot for NOTES has been developed to overcome these limitations and make the approach a feasible one.

The NOTES robot comprises a multifunctional robotic manipulator and a steerable and articulating drive mechanism. The robotic manipulator carries three interchangeable surgical tool tips in a cartridge that enables tool changing without removing the robot from the patient. A stereovision camera is attached at the tip of the robotic manipulator to provide real-time video feedback to the surgeon. A steerable articulating drive mechanism is connected to the robotic manipulator to guide the robot and navigate through a natural orifice. Besides its guiding capabilities, the drive mechanism is also shape-lockable which provides a stable platform for the robotic manipulator to perform surgeries.

The design process and engineering analysis for the articulating drive mechanism are discussed in detail in this thesis. The first-generation drive mechanism is designed and built as a proof of concept. Bench-top tests show that the design achieves the purpose of guiding and positioning the robotic manipulator. It is believed that the articulating drive mechanism can provide freedom of movement to the robotic manipulator and help circumvent some of the difficulties faced by approaches such as typical minimally invasive surgery (MIS). The second generation of the articulating drive mechanism is presented next, whereby the overall size of the drive mechanism is reduced significantly and the components in part of the drive transmission are also altered.

Phantom Omni joysticks from SensAble Technologies are used as control consoles for the drive mechanism. The programming for the drive mechanism controls has been developed and is presented in this thesis.

Although further improvements are necessary to the current iteration of the robot, bench-top testing results show promise of continued success for the multifunctional robot for NOTES.

Advisor: Carl A. Nelson