Robotic Minimally Invasive Tools for Restricted Access Confined Spaces

A study has been performed in the design and fabrication of deployable borehole robots into confined spaces. Three robot systems have been developed to perform a visual survey of a subterranean space where for any reason humans could not enter. A 12mm diameter snake arm was designed with a focus on the cable tensions and the failure modes for the components that make the snake arm. An iterative solver was developed to model the snake arm and algorithmically calculate the snake arms optimal length with consideration of the failure modes. A robot was developed to extend the range capabilities of borehole robots using reconfigurable borehole robots based around established actuation and manufacturing techniques. The expected distance and weight requirements of the robot are calculated alongside the forces the robot is required to generate in order to achieve them. The whegged design incorporated into the tracks is also analysed to measure the capability of the robot over rough terrain. Finally, the experiments to find the actual driving forces of the tracks are performed and used to calculate the actual range of the robot in comparison to the target range. The potential of reconfigurable mobile robots for deployment through boreholes is limited by the requirement for conventional gears, motors, and joints. This chapter explores the use of smart materials and innovative manufacturing techniques to form a novel concept of a self-folding robotic joint for a self-assembling robotic system. The design uses shape memory alloys fabricated in laminate structures with heaters to create folding structures

Development of a Novel Amphibious Locomotion System for use in Intra-Luminal Surgical Procedures

Colonoscopy is widely considered the gold standard for inspection of the colon. The procedure is however not without issue, current colonoscopes have seen little change or innovation throughout their 40 years of use with patient discomfort still limiting success. The aim of this PhD study was to develop a locomotion system for use on a robotic device that can traverse a liquid filled colon for atraumatic inspection and biopsy tasks. The PhD was undertaken as part of a larger two-centre EU project, which aimed to bring about a change in the way colonoscopy is done by moving to “robotic hydro-colonoscopy”. In this thesis the initial development and testing of an amphibious locomotion concept for use in a procedure known as hydro-colonoscopy is described. The locomotion system is comprised of four Archimedes’ screws arranged in two counter-rotating pairs. These aim to provide propulsion through a fluid-filled colon as well as provide locomotive traction against colonic tissue in partially fluid-filled or collapsed sections of the colon, such as the splenic flexure. Experimental studies were carried out on a single screw system in fluid and dual counter-rotating screws in contact conditions. These show the system’s ability to generate thrust in the two discrete modes of locomotion of the amphibious system. A 2:1 scale prototype of the proposed device was produced and features compliant screw threads to provide atraumatic locomotion. The scale prototype device was tested in ex-vivo porcine colon. The developed system was able to traverse through lumen to limited success, which demonstrated that this concept has the potential for use on an intra-luminal robotic device The key contributions of this research are: variable geometry locomotion system; amphibious locomotion using Archimedes’ screws; experimental assessment of the locomotion in fluid, contact and amphibious states; and analysis of the contact dynamics against tissue