Structural and physical measurements at the speed of light

Electrical sensors, such as strain gages and thermocouples, have for decades been the standard mechanism for converting physical and mechanical phenomena into an analog signal that can be measured by a data acquisition system. Advances related to sensor measurements have mostly been focused on signal conditioning and sensor design. The fundamental operation of sensors remained the same: measuring an electrical potential difference and scaling it to physical engineering units. Despite their ubiquity, electrical sensors have numerous limitations that make them unsafe, impractical, or unusable in many applications. Optical sensors overcome many of the challenges associated with electrical sensors by using light rather than electricity and standard optical fiber in place of copper wire. Optical fibers are non-conductive, electrically passive, immune to EMI-induced noise, and can transmit data over long distances with little or no loss in signal integrity. Intrinsic optical sensors use the optical fiber itself not only for signal transmission, but also as the sensing element to measure temperature, strain, pressure or other parameters. For most standard sensing applications, electrical sensing has been and will continue to be the best and most effective solution. However, optical sensors can offer an important alternative in traditionally challenging applications. Fiber optic sensing; structural test; structural health monitoring; fiber bragg grating; fabry-perot; backscattering; hybrid measurement system; foil strain gages; FBG; PXI; LabVIEW;