Large infrastructure is essential to Europe’s economic growth, yet ageing concrete structures are increasingly subject to failure. Novel technology using ultrasonic waves and radar pulses deployed on a climbing robot could effectively efficiently detect damage, ensuring structural integrity. Inspection of large public facilities such as hydroelectric dams, containment buildings, cooling towers and motorway bridges are often performed manually by setting up scaffolds that have to be moved around to inspect the whole surface. The use of scaffolds is however labour intensive and time consuming, and workers using gondolas run the risk of falling from a height. Seeking a way around this problem, researchers within the EU-funded project VORTEXSCAN sought to develop reliable, fast and cost effective techniques for inspection of large-scale concrete structures. The project team aimed to develop a vacuum-powered robot system that would autonomously navigate vertical curved surfaces of large infrastructures. The fast-moving air created by rotating an impeller forms a low-pressure vortex that is strong enough to make the robot adhere to any vertical surface. Deploying a combination of two non-destructive testing techniques (NDT) – ultrasonic transducer and ground-penetrating radar (GPR) – allows inspection of possible material defects. Combining the data from these two NDT techniques increases measurement accuracy, creating a more accurate representation of surface defects. Although the project did not meet all of its initial objectives, it successfully provided a ground penetration radar system with penetration capability of 40 cm over a curved surface of no more than 4 m in radius. Researchers tested the system in a controlled laboratory environment over an operating distance of no more than 1 m but true field tests were not performed. VORTEXSCAN’s proposed system could facilitate inspection of large vertical concrete structures, providing savings compared with the current manual periodic inspections. The system targets Europe’s electrical power industry structures such as nuclear reactor containment, dams and cooling towers. A large number of these infrastructure types are beginning to age, some of them having been built nearly a century ago.
Vacuum-powered, robot, curved surfaces, ultrasonic waves, ground penetrating radar, VORTEXSCAN