Using Embedded Fiber Bragg Grating (FBG) Sensors in Smart Aircraft Structure Materials

This paper describes the process of developing a smart material with monitoring application to the aircraft structures. A part of vertical stabilizer was selected and reproduced using carbon fiber honeycomb core sandwich panels. The sandwich panels reproduced were fabricated in accordance to the generic sandwich structure and aviation industry standards, including the materials and also the method of construction. Using a carbon fiber from Hexcel as the face-sheet, Nomex honeycomb as the core, the sandwich panel was cured using Hysol EA9330 resin according to aviation industry standard curing process. In order to make the sandwich panel as smart materials, optical sensor which has fiber bragg grating arrays, FBG, were embedded between the carbon fiber plies during the lay-out process. Using an FBG data logger, the FBG sensor signals were read before and after the FBG arrays were installed in the sandwich panels. From the initial measurement, the experiment was a success since the FBG sensors were readable and the difference in the signals was less than 1 nm. In the future, the specimen will be used for further experiment for measuring strains and establishing the existence of damage in the panel.