Low-cost/high-reproducibility flexible sensor based on photonics for strain measuring

Abstract

This paper presents a flexible sensor based on photonics for measuring strain, curvatures and vibrations. This flexible sensor is composed by a Fiber Bragg Grating (FBG) embedded into polydimethylsiloxane (PDMS). The selected FBG resonates at the wavelength of 1552.37 nm and is embedded before the curing for enabling a strong adhesion between both components. Few prototypes were fabricated and characterized. The measurements showed a maximum strain sensitivity of approximate to 400 pm per 1% elongation, revealing to be sensitive to strain/bending forces and vibration. The measurements allowed to establish a predictable response for both static and dynamic behavior, corresponding to a resolution of approximate to 88 pm per curvature degree. This flexible sensor also allowed high strain cycles and presented the linear behavior of approximate to 14 pm degrees C-1 over the temperature range 20-110 degrees C. The high-simplicity of the fabrication process results on low-cost with high-degree of reproducibility of their characteristics. (C) 2013 Elsevier Ltd. All rights reserved.