Innovators at NASA's Armstrong Flight Research Center have developed an optical waveguide fiber Bragg grating (FBG) that is sensitive to an external magnetic field. The technology allows direct coupling of the external field to the electromagnetic (EM) wave propagating in the fiber, bypassing the need to first measure strain. The properties of the waveguide material are directly and incontrovertibly influenced when exposed to an external field. In contrast to other FBG-based methods that detect external fields via a mechanical change (e.g., magnetostriction-induced strain), this innovation uses ferromagnetic nanoparticles to achieve a direct coupling of the external field to the optical behavior of the fiber. Thus, the technology can be used as a sensor to detect and map magnetic fields. Alternately, a known magnetic field can be applied to create a particular optical transmission behavior in the waveguide, thus creating an optical switch or selective filter.
This technology is part of Armstrong's portfolio of fiber optic sensing technologies. The innovation leverages Armstrong's cutting edge work in this area, including its patented FBG interrogation system, which allows for a diverse set of engineering measurements in a single compact system. In addition to magnetic field, other measurements include structural shape and buckling modes, external loads, and cryogenic liquid level. The system and measurement technology is commercially available for research applications. In addition to capitalizing on the significant advancements in fiber optic and laser technologies that have been made to support the telecommunications industry, Armstrong has also partnered with UCLA's Active Materials Lab (AML) to tap their expertise in the field of magnetics.
- Sensitive: Reduces the effects of extraneous thermal and mechanical influences
- Lightweight and compact: Lighter than many conventional electronic magnetic field devices
- High resolution: Allows high spatial resolution maps of magnetic fields
The benefits of this technology over traditional sensing methods make it a strong candidate for integration into a variety of sensing systems across a wide-range of industries, including:
- Military and homeland security: Detection of explosive devices
- Aerospace: Navigation, observations, altitude sensing
- Navigation: Ground transportation, backup for satellite GPS system
- Electromagnetic receptors/antennas
- Mineral exploration
- Oil and gas drilling
- Geophysical surveys
- Earth tectonics
Armstrong has one patent issued (U.S. Patent No.: 9,274,181) for this technology.
NASA invites companies to explore partnership opportunities designed to advance the development of this technology. Companies who are interested in developing and/or licensing this technology will have access to a strong support structure, including NASA Armstrong's patented fiber optic sensing portfolio, as well as UCLA's Active Materials Lab's expertise in magnetics.
If you would like more information about this technology or about NASA's technology transfer program, please contact:
Technology Transfer Office
NASA's Armstrong Flight Research Center
PO Box 273, M/S 1100
Edwards, CA 93523-0273
Phone: (661) 276-3368