Abstract
Foreign objects (FOs) ale one of the major causes of damage to airplanes, and may result in serious accidents. At present, visual detection of FOs is performed by humans. However, it takes long time and detection of FOs is sometimes difficult depending on the light condition and their colors. We propose a sensor system which has an ultraviolet image sensor to solve these problems and develop an automatic inspection system. In the ultaviolet range, strong highlights on ground objects are always made by the sky radiation component. This fact enables us to design a system which detects FOs robustly, regardless of the direction of the sun, the weather, and colors of FOs. The conditions for detecting FOs are studied in terms of reflectance, and their validity is shown by experiments.
