An Autonomous Inspection System for Runways Using Ultraviolet Image Sensors

• Published in: Eizō Jōhō Media Gakkaishi Vol. 56; no. 7; pp. 1096 - 1104
• Main Authors: Wajima, Hiroshi, Makino, Tatsuo, Sugiyama, Takahiro, Abe, Keiichi
• Format: Journal Article
• Language: Japanese
• Published: The Institute of Image Information and Television Engineers 01.07.2002
• ISSN: 1342-6907; 1881-6908
• DOI: 10.3169/itej.56.1096

This paper describes a sensor system for the detection of foreign objects (FOs) on airport runways. FOs are a major cause of damage to airplanes, and have led to serious accidents. Currently, airport workers visually inspect airport runways for FOs. However, this task is tough and dull; moreover, detection of FOs is difficult, under certain lighting conditions and when the objects are of colors similar to runways and low in height. We propose a sensor system which solves these problems by applying an ultraviolet image sensor and a laser radar for an automatic inspection system that we developed. In the ultraviolet range, objects on the ground are always strongly highlighted by the sky radiation component of the sun's radiation in the daytime. This allows to design a system which is robust in detecting FOs, i.e., it detects the FOs regardless of the direction of the sun, the weather, and the colors and height of the objects. The conditions for the detection of FOs in terms of reflectance are studied, and the validity of the conditions is demonstrated through experiments.