Automated video processing and image analysis software to support visual inspection of AGR cores

摘要

Remote visual inspection of fuel channels in Advanced Gas-cooled Reactor (AGR) cores provides nuclear operators with an understanding of the condition of the UK’s fleet of nuclear power plants. During planned, periodic outages, specialist inspection tools equipped with video cameras and other sensors are manipulated inside fuel channels selected for inspection and a video of the entire channel bore is recorded for each. If cracks are observed in this process, a montage of the entire crack region needs to be: produced, analysed and sentenced (classifying the crack morphology, location, orientation and size) before the station is returned to service – provided it is safe to do so. At the present time, the video analysis and crack montage production is done manually by an expert team of inspection engineers. In line with this process, bespoke image stitching software named “ASIST” (Automated Software Image Stitching Tool) has been trialled in the last 12 months and evaluated using data from: Dungeness, Hunterston B, Hinkley Point B, Heysham 1 and Torness outages. The software is now almost ready to replace the manual process and will provide higher quality images with 100% channel visualisation properties in a fraction of the time taken by the current approach. This paper provides a summary of the ASIST evaluation undertaken in the last year. It also describes recent research endeavours aiming to provide ASIST with: crack detection techniques; keyway locating algorithms and methods to compute Structure-from-Motion which will facilitate the extraction of 3D depth information directly from the 2D video footage.