Evaluation of Small Bolt and Nut Detection Performance Using Airport Runway Foreign Object Debris Detection System Based on a 96-GHz Millimeter-Wave Radar System

The automatic airport foreign object debris (FOD) detection system enables the safety and security operations of airport runways. In this regard, we developed an FOD detection system based on an optically connected 96-GHz distributed-type millimeter-wave radar sensor. In this paper, the small bolt and nut detection performance of the developed FOD detection system is obtained at an airport runway. The detection probabilities of six different bolt and nut samples, which included an M10 bolt and nuts with different lengths (2, 4, 6, and 8 cm), an M10 nut, and an M4 bolt and nut (length: 2 cm), are evaluated. Almost all samples, except for the M10 bolt with an 8-cm length, are smaller than the objects described in a standard document. From the measurement results, we confirm that the detection rate exceed 95% for all sizes of M10 bolts and nuts.