Stress-insensitive vector curvature sensor based on a single fiber Bragg grating

Abstract A stress-insensitive vector curvature sensor based on a single fiber Bragg grating (FBG) is proposed and experimentally demonstrated. The sensor is easily fabricated by encapsulating an FBG on a thin steel plate with ultraviolet glue. When the FBG deviates from the neutral plane, its effective refractive index and grating constant are changed by bending, therefore, the sensor can realize the curvature measurement. The sensitivity of the sensor in convex bending is 553.65 pm/m−1 in the range of 0.4798–1.3569 m−1. The sensor can realize vector measurement of curvature due to the opposite stress direction on the two sides of the neutral plane during bending. The concave curvature sensitivity of the sensor is −811.19 pm/m−1 in the range of 0.4798–1.3569 m−1. Due to the large stiffness of the thin steel plate, the package of the FBG makes it insensitive to small axial stress. The favorable stability of the sensor facilitates its practical application in the measurement of curvature and inclination. This sensor has the advantage of simple manufacture, low cost, and easy industrial production.

[1]  A. Siqueira,et al.  Quasi-Distributed Torque and Displacement Sensing on a Series Elastic Actuator’s Spring Using FBG Arrays Inscribed in CYTOP Fibers , 2019, IEEE Sensors Journal.

[2]  Arnaldo G. Leal-Junior,et al.  Polymer Optical Fiber Sensors in Wearable Devices: Toward Novel Instrumentation Approaches for Gait Assistance Devices , 2018, IEEE Sensors Journal.

[3]  Xinyong Dong,et al.  An Optical Fiber Curvature Sensor Based on Two Peanut-Shape Structures Modal Interferometer , 2014, IEEE Photonics Technology Letters.

[4]  Peiguang Yan,et al.  Ambient refractive index-independent bending vector sensor based on seven-core photonic crystal fiber using lateral offset splicing. , 2013, Optics express.

[5]  Xinyong Dong,et al.  An optical fiber curvature sensor based on photonic crystal fiber modal interferometer , 2013 .

[6]  Xinyong Dong,et al.  Polarization-dependent curvature sensor based on an in-fiber Mach-Zehnder interferometer with a difference arithmetic demodulation method. , 2012, Optics express.

[7]  Soong Ho Um,et al.  Ultra-high curvature sensors for multi-bend structures using fiber Bragg gratings. , 2019, Optics express.

[8]  Lianqing Zhu,et al.  Simultaneous measurement of bending and temperature based etched PMFBG FP filter , 2019, Optics & Laser Technology.

[9]  A. Frizera-Neto,et al.  Polymer Optical Fiber Bragg Gratings in CYTOP Fibers for Angle Measurement with Dynamic Compensation , 2018, Polymers.

[10]  Yunshan Zhang,et al.  Two-dimensional microbend sensor based on long-period fiber gratings in an isosceles triangle arrangement three-core fiber. , 2017, Optics letters.

[11]  Carlos A. F. Marques,et al.  Perrogator: A Portable Energy-Efficient Interrogator for Dynamic Monitoring of Wavelength-Based Sensors in Wearable Applications , 2019, Sensors.

[12]  Wojtek J. Bock,et al.  Highly sensitive bend sensor with hybrid long-period and tilted fiber Bragg grating , 2010 .

[13]  Highly sensitive vector curvature sensor based on a triple-core fiber interferometer , 2019, OSA Continuum.

[14]  Libo Yuan,et al.  Temperature insensitive one-dimensional bending vector sensor based on eccentric-core fiber and air cavity Fabry-Perot interferometer , 2017 .

[15]  Shuqin Lou,et al.  High-Performance Bending Vector and Strain Sensor Using a Dual-Tapered Photonic Crystal Fiber Mach–Zehnder Interferometer , 2019, IEEE Sensors Journal.

[16]  A. Siqueira,et al.  Fiber Bragg grating-based sensor for torque and angle measurement in a series elastic actuator's spring. , 2018, Applied optics.

[17]  Ming Ding,et al.  Intensity measurement bend sensors based on periodically tapered soft glass fibers. , 2011, Optics letters.

[18]  Libo Yuan,et al.  Highly Sensitive Vector Curvature Sensor Based on Two Juxtaposed Fiber Michelson Interferometers With Vernier-Like Effect , 2019, IEEE Sensors Journal.

[19]  Bo Liu,et al.  Highly Compact Vector Bending Sensor With Microfiber-Assisted Mach– Zehnder Interferometer , 2019, IEEE Sensors Journal.

[20]  Lianqing Zhu,et al.  Fiber Brag grating monitoring of a morphing wing based on a polyvinyl chloride reinforced silicone substrate , 2019, Optical Fiber Technology.

[21]  Xinyong Dong,et al.  All fiber curvature sensor based on modal interferometer with waist enlarge splicing , 2013 .

[22]  P. Caldas,et al.  All-fiber Mach-Zehnder curvature sensor based on multimode interference combined with a long-period grating. , 2007, Optics letters.

[23]  Tiegen Liu,et al.  Temperature-insensitive curvature sensor based on anti-resonant reflection guidance and Mach–Zehnder interferometer hybrid mechanism , 2019, Applied Physics Express.

[24]  Zhenhong Jia,et al.  High-Sensitivity Displacement Sensor Based on a Bent Fiber Mach–Zehnder Interferometer , 2013, IEEE Photonics Technology Letters.

[25]  Libo Yuan,et al.  Bending sensor with parallel fiber Michelson interferometers based on Vernier-like effect , 2019 .