FBG sensor network for pressure localization of spacecraft structure based on distance discriminant analysis

Structure used in aircrafts and spacecrafts often undergo high pressure loading that can produce various types of damage, thus prediction of existence and pressure position is important to damage localization. In this paper, the structure type investigated is a 50 mm thick sandwich panel with aluminum face-sheets and aluminum honeycomb core. One pressure test was performed on the panels, which was instrumented with 9 FBG sensors. The signals recorded at the various sensor locations varied with regard to Bragg wavelength shift of FBGs. Using this information and combining it with a localization algorithm based on distance discriminant analysis, the pressure location could be successfully determined. A description of the FBG sensors network and the mathematical model to determine the pressure location is provided. The pressure tests on the spacecraft structure, the response of the FBG sensors network and the analysis performed to determine the pressure location are described.