Project Title:
Grating-Based Fiber-Optic Sensor Arrays for Smart Aerospace Materials
94-1 04.03 4107
Grating-Based Fiber-Optic Sensor Arrays for Smart Aerospace
Materials
Abstract:
Intelligent Fiber Optic Systems proposes a new approach for
including sensing and processing functions in aerospace
materials. This integrated structure exploits novel combination
of compatible and complementary known techniques: (a) Lattice
Sensor arrays (LSAs), (b) Two-Mode Fibers (TMFs), (c) Two-Mode
Couplers TMCs, (d) Fiber Bragg Gratings (FBGs), (e) Active
(piezo-electric, electro- or magnetostrictive) Materials (AMs).
LSAs provide efficient sensing interconnection networks with an
input bus for distributing optical energy to sensors and output
bus for collecting sensed signals. Using TMFs means these buses
are modally separate but in a single fiber. TMCs allow modal
multiplexing. FBGs perform sensing and modal cross-coupling
functions. In general, measurands disturb FBGs, thereby shifting
their Bragg wavelengths measured by a demodulation subsystem. A
TMF/TMC/FBGbased LSA is itself electromagnetic interference-
immune and adds intelligent health monitoring functions to
passive aerospace structures. Localized transducer sensitivity
(temperature, electromagnetic field, voltage, etc.) and enhanced
intelligence is given by coating or embedding the FBGs in
"active" materials. In Phase I, a single-sensor prototype will
be constructed and evaluated for sensitivity, dynamic range,
linearity, reliability and installation options.
As well as smart aerospace material applications (for space
station, spacecraft and aircraft applications), real-time space,
lunar and planetary environmental monitoring systems, and
intelligent buildings in lunar and other hostile environments,
significant potential for commercial spinoffs exists in
intelligent transport sytems, roads, bridges, automobile and
submarine manufacturing. The proposed sensing networks offer
higher sensitivity and reliability than those of conventional
approaches and can be mass produced. These features make the
proposed smart sensors marketable and can attract follow-on non-
federal and private sector funding.
Key Words
Intelligent Fiber Optic Systems
1778 Fordham Way
Mountain View, CA 94040