Life Cycle Performance Screening Using Fiber Optic Grating Sensor Systems for Composite Cryogenic tankage

"Single and multi-axis fiber grating strain sensors were used to detect damage in a Phase I composite cryogenic tank. Acoustic signatures were collected from multiple fiber grating sensors during impact. Multi-dimensional strain field measures were usedto measure damage remotely through three cryogenic cycles. The first cycle occurred prior to impact and the second and third after two subsequent impacts directed to the vicinity of selected fiber grating strain sensors. The Phase II effort will bedirected toward the development of a prototype fiber grating sensor system that can be used to localize and quantitatively evaluate damage and assess the health of composite cryogenic tanks. The prototype system will include single and multi-axis fibergrating strain sensor packages optimized for the composite cryogenic tank environment as well as hardware and algorithms necessary for efficient and cost effective diagnostics."