Assembly Defect Detection Using Rivets in Aeronautical Structures.

During the flight, the aircraft structure undergoes many vibrations due to aerodynamics and external factors such as atmospheric turbulence. These vibrations don't allow the assembly of the different parts of an aircraft by welding because the bond between two welded parts is very fragile and it can break especially at high frequency vibrations. In aeronautics, the assembly is made using the rivets system that makes the bond between the aircraft parts more flexible and provides the necessary resistance to high frequency vibrations exerted on the aeronautics structure in mid-flight. For example, an aircraft wing has thousands of rivets of different types (flat, Button, countersunk flat, full or hollow...) and different sizes (the diameter varies between 2mm and 5mm). The verification of the bad fixing and the bad distribution of the glue on the rivets isn't an easy task, especially that the addition of the glue is very necessary to increase the resistance of the rivets to the vibrations. The repair of these assembly defects using rivets is very expensive. In this paper, we propose a non-destructive testing method to detect the existence of the glue on the rivet and to check the diameter and the position of the holes where the rivets are fixed.