Bending losses in optical fiber result in additional propagation losses when light is coupled from core modes to cladding modes as the fiber is bent. This effect becomes significant once a certain critical radius of curvature is reached, and its value increases considerably at longer wavelengths as the modes become less confined to the nucleus. In this way, flexion sensors have had a wide range of applications, including structural monitoring, motion detection in devices for biomedical purposes, and robotic configurations, among others. This article studies the bend-loss in two single-mode fiber embedded in two different silicones and arranged in a circular shape. The experiment is carried out in two parts by vertically inserting pressure with a C-clamp into a bent optical fiber silicone-filled mold while holding the initial condition constant to induce bend-loss in a four-turn fiber. In both sensors, optical fiber was coiled a total number of 4 times with a diameter of 4.8 cm and 5.0 cm. Each mold has different characteristics, e.g., density, 1050.92 mg/cm3 and 878.33 mg/cm3. It is found that both sensors are suitable for measuring pressure, but the difference comes in the range of measurements, the denser sensor can measure 2.12 dB per lap, while the less dense sensor can measure 0.70 dB per lap. Also, an Arduino program connected to a web analyzer is used to access the data on a computer in real time.
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