Abstract:
The wheel assembly is one of the most critical parts of an aircraft. Landing, take off and taxi
operations generate repetitive stresses on the wheel hubs, resulting in small imperfections or damage
that can potentially grow into cracks. These cracks may cause catastrophic failures that harm the
passengers’ lives. At present, the Sri Lankan aviation industry uses handheld eddy current inspection
equipment for aircraft wheel hub inspection. The handheld inspection method reduces the accuracy
of the testing. This study proposes a design of a pre-coordinated eddy current inspection mechanism
using Arduino programming. Component Maintenances Manual (CMM) provides by the aircraft
manufacture describes the standard inspection methodology of the wheel hub. According to the
CMM, the beading area of a wheel hub should be thoroughly inspected as the beading area has
repetitive stress concentration. The inspection is done by the rotating wheel hub on a rotary table, and
placing a scanning probe on the surface at the top of the bleeding area gradually moves down the
probe in 2 mm steps. When the machine operates, there is relative motion between the wheel hub and
the moving arm. In order to reduce the moment of inertia, the tray rotates at 50 RPM. On the
assembling step, a collision check was done on mates. The time for each wheel hubs with change
concerning the size of the wheel hub. If someone chooses the wrong size, the probe might be
damaged so, safety switches have been installed on the moving arm as a safety feature. The proposed
design was aimed to inspect four types of wheel hubs (wheel sizes: A330 (main and nose wheel),
A320 (main and nose wheel). These sizes have been coded on the Arduino code. The proposed
design will facilitate high accuracy, time-efficient, and low-budget NDT inspection operation.
Keywords: Non-destructive testing; Eddy current; Crack damage; automated inspection system,
Aircraft maintenance
