Design study of an earthquake rescue robot

This thesis describes the design of a brush robot for earthquake rescue and for traversing pipes with varied cross sectional shape. Earthquake rescue is a very dangerous, difficult and challenging task, in which emergency services rescue people who are trapped in man-made structures, such as collapsed buildings after an earthquake. The building collapse may have been caused by natural or man-made events. This technology is also applicable to tunnel collapse and land slips. The focus of this work is finding the location of victims and provision of primary life support and communications. To illustrate the concept of the robot, the thesis first discusses the current development of rescue robots and pipe robots. Then the thesis focuses on the description of a brush based pipe robot, developed by the University of Durham, which would be used as the basis of an earthquake rescue robot. The concept of the robot was illustrated and compared with other current rescue robots and pipe robots. After outlining the advantages of this robot concept, a robot body shape change theory was proposed and theoretical simulations were used to verily the practicality of the robot shape change theory. The thesis also illustrates the design of the working principle and design of a robot sensor, which was subsequently used in the robot shape change experiments. The robot body shape change experiments and the experimental results are described and discussed. The experimental results illustrate the robot concept and support the robot body shape change theory. Chapter 6 focuses on the brush unit traction investigation, bristle theory and mathematical model. Furthermore, the bristle theory and mathematical model were used to explain the variation of traction force in the traction experiments

Microwave based monitoring system for corrosion under insulation

This thesis presents the work undertaken by the author within the institute of Signals, Sensors and Systems in the school of Engineering and Physical Sciences at Heriot-Watt University, Edinburgh. The main aim of the research was to design and develop a non-destructive sensor capable of monitoring the onset of corrosion under insulation. The development of the sensor has involved the design of a complete system to stabilise and control the sensor, the development of a COMSOL model to understand the progression of corrosion to determine the remaining useful life of the asset, and an investigation into horn antenna design to inform the design of the optimal sensor head. The designed sensor system was tested with a variety of samples to benchmark the effectiveness of the sensor and prove the concept viability as a product. Experiments proved the concept of sensing defects in metallic surface with or without insulation layers. Samples simulating real life corrosion were tested to prove the resilience of the sensor when defects were less guaranteed. Remaining useful life estimations were conducted on simulated defects to show the sensor ability to become a smart sensor using prognostic health management techniques. Finally the environmental tests were conducted to ensure the sensor was indeed nondestructive, confirming that all aspects of the research had been successfully completed

Imaging of buried utilities by ultra wideband sensory systems

Third-party damage to the buried infrastructure like natural gas pipelines, water distribution pipelines and fiber optic cables are estimated at $10 billion annually across the US. Also, the needed investment in upgrading our water and wastewater infrastructure over the next 20 years is estimated by Environmental Protection Agency (EPA) at$400 billion, however, non-destructive condition assessment technologies capable of providing quantifiable data regarding the structural integrity of our buried assets in a cost-effective manner are lacking. Both of these areas were recently identified several U.S. federal agencies as \u27critical national need\u27. In this research ultra wideband (UWB) time-domain radar technology was adopted in the development of sensory systems for the imaging of buried utilities, with focus on two key applications. The first was the development of a sensory system for damage avoidance of buried pipes and conduits during excavations. A sensory system which can be accommodated within common excavator buckets was designed, fabricated and subjected to laboratory and full-scale testing. The sensor is located at the cutting edge (teeth), detecting the presence of buried utilities ahead of the cutting teeth. That information can be used to alert the operator in real-time, thus avoiding damage to the buried utility. The second application focused on a sensory system that is capable of detecting structural defects within the wall of buried structures as well as voids in the soil-envelope encasing the structure. This ultra wideband sensory system is designed to be mounted on the robotic transporter that travels within the pipeline while collecting data around the entire circumference. The proposed approach was validated via 3-D numerical simulation as well as full-scale experimental testing

Dangerous Inspection & Versatile Exploration Robot (DIVER): Tracking, Monitoring and Assisting Human Divers in Commercial, Environmental and Military Applications

The Dangerous Inspection & Versatile Exploration Robot (DIVER) is an underwater remotely operated vehicle designed to assist, track and monitor professional scuba divers in commercial, research and military applications. Integration of custom and commercially available components allowed for hardware development of the ROV. Software development allowed for the integration of OpenTLD tracking algorithm and manual user controls for full autonomous or tele-operational missions. DIVER provides constant communication for the improvement of mission organization and professional diver safety

Investigations on corrosion monitor reliability, calibration, and coverage

Thickness loss due to internal corrosion and erosion is a critical issue in ferromagnetic steel structures that can cause catastrophic failures. Ultrasonic thickness gauges are widely used for the detection of wall thickness. Recently permanently installed ultrasonic sensors have become popular for the inspection of areas suspected to undergo wall thickness loss. However, these are limited by the high cost and requirement of coupling agents. To address these problems, a novel cost-effective, and smart corrosion monitor based on the magnetic eddy current technique is developed in this research. The performance and reliability of the monitor to track internal wall thickness loss is tested successfully through accelerated and real-life aging corrosion tests. Due to the handling and safety issues associated with the powerful magnets in magnetic techniques, a particle swarm-based optimisation method is proposed and validated through two test cases. The results indicate that the area of the magnetic excitation circuit could be reduced by 38% without compromising the sensitivity. The reliability of the corrosion monitor is improved by utilising the active redundancy approach to identify and isolate faults in sensors. A real-life aging test is conducted for eight months in an ambient environment through an accelerated corrosion setup. The results obtained from the two corrosion monitors confirm that the proposed corrosion monitor is reliable for tracking the thickness loss. The corrosion monitor is found to be stable against environmental variations. A new in-situ calibration method based on zero-crossing frequency feature is introduced to evaluate the in-situ relative permeability. The thickness of the test specimen could be estimated with an accuracy of ± 0.6 mm. The series of studies conducted in the project reveal that the magnetic corrosion monitor has the capability to detect and quantify uniform wall thickness loss reliably

Capacitive sensor technology for polyethylene pipe fault detection

This work develops a Finite Element Analysis simulation to determine if capacitive sensors can be used to detect defects in polyethylene gas distribution pipes. Currently, there is no in ground detection system to find the defect. Catastrophic results can occur if gas leaks are present and ignite. Finite Element Analysis (FEA) software will be used to simulate how different shapes and sizes of capacitive sensors affect the electric field, which affect capacitance when the dielectric of a material changes. An optimal electrode size and shape was chosen from these simulations, built, and tested at the Battelle Pipeline Safety Research & Development Program. The sensor was run through multiple tests on a thirteen foot long, six inch diameter polyethylene pipe with a half inch wall thickness where random defects were placed in the pipe. Upon completion of the test, the data was analyzed, and it determined that the capacitive sensor detected all known defects in the polyethylene pipe