Research On Application Of Image Processing Technology For Outer Surface Defects Of Transport Aircraft

The ground inspection is an essential item of line-maintenance in civil aviation.Currently,there are many ground inspection items(including 21 points,totaling over 100 items).During the inspection process,due to the human factors of the inspectors and the dark or bad weather,the external surface damages such as subtle cracks,lightning damage,and fatigue cracks were not discovered in time,which may lead to major safety accidents.It can be seen that the research of the transport aircraft defect is conducive to the development of the survey equipment to assist the maintenance personnel to complete or achieve a satisfactory completion of the ground inspection work,and ultimately to ensure the normal operation of the flight.Based on a large number of external surface damage images collected by the airline engineering departments of several domestic airlines,the image of the typical damage type was selected as the research object in this paper.Due to the fact that there are no finished products and research materials on the external surface inspection equipment for civil aviation transport aircraft at home and abroad,aiming at the characteristics of differences in damage sites and common features in different damage type images,common image processing algorithms were sought to find.The image was first de-noised and the image segmentation process was performed.The wavelet multi-scale threshold technique was used in the denoised of damaged images,and the threshold was adaptively optimized at the same time.Broken image segmentation used wavelet maximum modulus multi-scale edge detection and compressed sensing edge detection methods.By using this method,six typical types of damage images were dealt with: body skin lightning damage,engine fairing foreign body impact damage,wheel rim damage,wheel fatigue crack damage,airframe wind damage and wing foreign body impact damage.Obtained processed images can be better used for machine identification of surface defects such as cracks,wind erosion,and impact damage etc.