Previously in this blog, and elsewhere, we’ve extolled the virtues of FBGs — like their small size, immunity to EMI, and resistance to corrosive environments. In a recent paper in the Journal of Power Sources, Nigel A. David and a team from the University of Victoria, Canada have demonstrated the importance of each of these FBG sensor characteristics for their application. David and his colleagues are interested in polymer electrolyte membrane fuel cells. These are thin, flat structures that have an electrochemically active environment inside. David et al detail how others have tried electrical and infrared optical techniques to characterize the performance of PEMs and how these methods come up short. David concludes that using embedded FBG sensors “reliably measure[s] temperature dynamically with a relative resolution of less than 0.2 DEG C,” and is an inexpensive approach that may prove useful for understanding current distribution across the PEM cell.
FBG measurements in this study involved both Micron Optics instrumentation and sensors, specifically the sm130 Optical Sensor Interrogator and os1100 FBGs. See the full paper at: Science Direct
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FBG sensors are incredibly versatile.  They’re used in tiny medical devices and on huge bridges.  Often FBG and other types of fiber optic sensors are chosen when many measurements are needed over a long distance and the environment is harsh.  A good example of this is the use of FOS in geosynthetic materials used to reinforce earthworks. TenCate Geosynthetics will soon release a new product called Tencate GeoDetect.  It’s a geotextile fabric with fiber optic sensors integrated onto it.  Wilson Harvie, Director of Global Business Development for GeoDetect, will lead this product rollout.   Speaking recently to industry experts, Wilson said “Tencate GeoDetect is the first sensor enabled geotextile on the market.  Approximately five years ago TenCate began work on creating an “intelligent” geotextile.  We discovered a way to embed fiber optic lines onto a geotextile fabric without damaging the fiber.  Our initial work was with FBG technology but has now grown to encompass Brillouin and Raman technologies.  We are able to place multiple fiber optic lines on geotextile fabric up to 5.3 meters wide that provides all of the functionality of a geotextile; reinforcement, drainage, separation and filtration as well as provide a mechanism for data acquisition.  We have also found that in addition to the functionality of a geotextile, Tencate GeoDetect provides a “distributed anchoring” system which provides an excellent interface with the soil.  Our tests have shown that almost all of the strain that occurs in the earth structure is transferred to the fiber optic line.”   Micron Optics is a key partner to TenCate Geosynthetics for interrogation equipment and fiber optic expertise.  Find product description sheets, case studies and technical papers on Tencate GeoDetect at http://www.tencate.com/smartsite.dws?id=8718
Micron Optics has just released the os3150, a rugged strain gage based on fiber Bragg grating (FBG) technology. Optimized for outdoor installations on steel structures, the os3150’s stainless steel carrier holds the FBG in tension and protects the fiber during installation.  Like the os3110 and os3120, installation is quick and easy.
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In side by side comparisons with foil strain gages, the os3150 is equally sensitive and accurate, while providing for greater strain range and 100 times more fatigue life. The os3150 strain gage is qualified for use in harsh environments and delivers the many advantages inherent to all FBG based sensors.