Effective wound management and tissue repair is of significant importance for our increasingly ageing population. The aims of this research were to develop natural polymeric nanofibrous materials and investigate their potential for use in wound dressings and tissue engineering scaffolds; the enhanced performance of which, will improve patient comfort and recovery. This work has focused on the fabrication of alginate nanofibrous materials by electrospinning.

Recent progress in advanced surgical technology has been towards smaller devices enabling complex procedures to be performed via ever less invasive routes of entry. The ultimate extrapolation of this is the complete internalisation of surgical tools, integrating the benefits of a minimally invasive approach with the freedom of access and visualisation associated with open surgery. Although steps have been made towards the realisation of such 'intra- corporeal' robotics, an independently mobile internal device has not yet been demonstrated. This thesis constitutes the first step in the delivery of a fully internalised surgical device capable of free navigation within the peritoneal cavity. The first essential function of such a device is that it must adhere reliably to the peritoneal lining without causing mechanical or chemical damage. An adhesion mechanism able to harness local surface effects and inspired by attachment systems found on the feet of climbing reptile and insect species in nature is proposed. This type of biomimetic adhesion to internal body surfaces has yet to be demonstrated, and presents a significant engineering challenge given the complexity of the peritoneal surface. However, within this thesis a repeatable methodology is developed, using a range of micro- and nano- structured polymer surfaces, to assess the mechanisms of adhesion available in this environment and how they may be exploited. The test surfaces include a new micro-pillar surface, designed and fabricated specifically for the purposes of the research. Analyses of the peritoneal surface, the polymer topography and the physical processes that occur when they are brought into contact have been combined to provide an improved understanding of wet adhesion at a soft, biological interface. As a result of the new findings within the thesis, the first step in the design of an intra-peritoneal surgical device has been made.

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In recent years, robot assisted Minimally Invasive Surgery (MIS) is playing an increasingly important role in surgery. Although the benefit of reduced patient trauma and hospitalisation with improved prognosis has been achieved through the enhanced dexterity and accuracy of instrument manipulation by the introduction of robotic assistance, the use of current master-slave platform has inevitably imposed the increased physical separation that deteriorates the hand-eye coordination due to a lack of haptic feedback. To this end, the concept of Virtual Fixtures (VFs) and Active Constraints has attracted significant research interests. It provides in situ effective guidance of access routes to the target anatomy safely. However, its clinical potential is only well established for procedures such as orthopaedic surgery, which are conducted under a static frame-of-reference due to the relatively rigid anatomy involved. The main focus of this thesis is concerned with modelling spatial constraints that are adaptive to tissue deformation. These constraints define safe manipulation margins for an entire robot rather than just its end-effector. An analytical framework is proposed to control an articulated flexible robotic device. Provided with these dynamic active constraints, the framework enables the operator to perform smooth articulation or steady navigation along curved anatomical pathways even under rapid tissue deformation. The challenges induced by hyper-kinematic redundancy of the robot and increased computational burden of real-time haptic rendering are addressed so that they facilitate seamless interaction with the robot by using lower degree-of-freedom (DoF) haptic interfacing device. Furthermore, the use of a gaze contingent paradigm is also investigated to enhance the human-robot interaction by linking the manipulation constraints with visual track. To demonstrate the practical nature of the proposed framework, detailed quantitative validations were conducted on groups of subjects. Future directions and potential improvements to the proposed techniques are finally outlined.

The integration of robotic technologies in surgical instrumentation has contributed to the further development of Minimally Invasive Surgery (MIS) aimed at reducing the patient trauma and hospitalisation costs. Recent advances in imaging and mechatronics promise to enable the execution of more complex interventions through a single incision or natural orifice access. The main requirement for such procedures is the ability to reach the operative target through complex routes and curved anatomical pathways whilst maintaining adequate stability for tissue manipulation. A mechatronically controlled device with a high degree of articulation can potentially fulfil these requirements. However, the incorporation of a high number of Degrees-of-Freedom (DoFs) increases the control complexity of the system. The purpose of this thesis is to investigate different methods for reducing the control dimensionality of a hyper-redundant snake-like articulated robot for MIS. The design of the robot is based on a modular, flexible access platform featuring serially connected rigid links and a hybrid micromotor-tendon actuation strategy to construct independently addressable universal joints. A path length compensation scheme for reducing the backlash at the joint is presented, together with experimental evaluation of the joint positioning accuracy when using our proposed kinematic control. The integration of an extra translational DoF along the joint axis allows the performance of a hybrid 'inchworm-snake' locomotive scheme for self-propulsion of the device. This 'front-drive back-following' approach is implemented by actuating only one module at a time in a serial fashion. Therefore, the operator only needs to steer the distal tip of the device while the body of the robot follows the desired trajectory autonomously. Once the distal tip of the hyper-redundant device has reached the target operative site, the body of the robot has to adapt its shape to the surrounding moving organs while keeping the end-effector stable. A DoF minimisation algorithm is designed to identify the minimum number of joints to be simultaneously actuated to ensure shape conformance whilst simplifying the control complexity of the system. Finally, optimal kinematic configurations of the platform are derived for performing two specific single incision procedures. The results, based on workspace requirements estimated through pre-operative imaging of the patients, demonstrate the suitability of the system for such procedures. Results from in vivo experiments on porcine models are also provided to show the potential clinical value of the device.

This thesis described the research carried out on the development of a novel hardwired tactile sensing system tailored for the application of a next generation of surgical robotic and clinical devices, namely a steerable endoscope with tactile feedback, and a surface plate for patient posture and balance. Two case studies are examined. The first is a one-dimensional sensor for the steerable endoscope retrieving shape and 'touch' information. The second is a two-dimensional surface which interprets the three-dimensional motion of a contacting moving load. This research can be used to retrieve information from a distributive tactile sensing surface of a different configuration, and can interpret dynamic and static disturbances. This novel approach to sensing has the potential to discriminate contact and palpation in minimal invasive surgery (MIS) tools, and posture and balance in patients. The hardwired technology uses an embedded system based on Field Programmable Gate Arrays (FPGA) as the platform to perform the sensory signal processing part in real time. High speed robust operation is an advantage from this system leading to versatile application involving dynamic real time interpretation as described in this research. In this research the sensory signal processing uses neural networks to derive information from input pattern from the contacting surface. Three neural network architectures namely single, multiple and cascaded were introduced in an attempt to find the optimum solution for discrimination of the contacting outputs. These architectures were modelled and implemented into the FPGA. With the recent introduction of modern digital design flows and synthesis tools that essentially take a high-level sensory processing behaviour specification for a design, fast prototyping of the neural network function can be achieved easily. This thesis outlines the challenge of the implementations and verifications of the performances.