Structural health monitoring of a full-scale composite structure with fiber-optic sensors

Structural health monitoring systems capable of assessing structural integrity during manufacture and service would allow us to keep them up-to-date and to increase their lifetime and safety in use. We installed fiber-optic sensors into a full-scale composite structure of a Japanese experimental re-entry vehicle and monitored temperature and strain distributions of the fuselage during the manufacturing process. The results obtained us with important information about the process control and the structural quality. The sensing system used in the manufacture could measure strain also in structural tests with static load. Although the strain measured by the fiber-optic sensor was averaged data depending on the spatial resolution, the overall deformation of the structure could be found, because strain was acquired extensively and continuously along the sensing fiber. The achievement of this study shows applicability of fiber-optic sensors to structural health monitoring for composite structures.