Abstract：To measure the depth and width of scratches on surfaces such as aircraft fuselage skin and cabin glass, a scratch measurement device based on an embedded system has been developed. The device is designed based on the principle of light-section, using an embedded ARM development board, connecting an camera and an microscope. The camera collects images of parallel light strips projected by the projection module modulated by the measured surface. After image processing and scratch feature extraction, the depth and width of scratches are calculated, and the results can be digitized and saved. The experimental results show that the indication error of the device within the measurement range of 0.005～0.060mm does not exceed ± 2.0μm. The relative indication error within the measurement range of 0.060～2.000mm is less than ±4%. The device is miniaturized, integrated, high-precision, fast, and easy to operate, which is suitable for measuring scratches on various parts of the aircraft on-site.
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2024, Vol. 45 
