The ''smart patch'' approach which is based on self-monitoring would considerably alleviate the certification concerns for implementing bonded composite repairs to primary aircraft structures. This approach relies on the ability to autonomously detect disbonding in the patch, i.e. the smart patch approach is basically a continuous safety-by-inspection approach for the bonded repair. Studies on laboratory coupon specimens have shown that the concept of the smart approach using autonomous patch health monitoring systems appears to be viable. The main aspects of two in-situ patch health monitoring systems, to be applied to a composite bonded reinforcement on an operational F/A-18 aircraft, were outlined in this paper. The two systems being developed consist of a piezoelectric film-based and a CSG (Conventional resistant-foil Strain Gauges)-based sensing system. The latter system uses a primary cell (Lithium-based battery) as the power source while the former system is self-powered and has been designed to operate using the electrical power generated by an array of piezoelectric films, which convert structural dynamic strain to electrical energy. In both systems the patch health data is up-loaded by the operator using a wireless technique.
Application of a smart patch on an F/A-18 aileron hinge
Verwendung eines intelligenten Flickstückes an einem F/A-18-Querruderscharnier
2002
8 Seiten, 6 Bilder, 11 Quellen
Conference paper
English