Sensing characteristics study of fiber Bragg grating for nonlinear ultrasonic

Abstract Fiber Bragg Grating (FBG) has been widely used in temperature and strain measurement. Its center wavelength drift is affected by both temperature and strain. The influence of temperature and strain on center wavelength should be decoupled when measuring. In this paper, the sensing characteristics of FBG which pasted at different angles were simulated and analyzed, and it was found that FBG sensing for strain has strong directivity. A dual FBG composite construction based on the directivity of FBG sensing was proposed. Two FBGs were at an Angle of 62°. One FBG was sensitive to both temperature and strain, and the other was only sensitive to temperature. The structure can realize the decoupling of temperature and strain, and it doesn’t depend on feature of cantilever beam. It was verified by experimental analysis that the decoupling result was good by utilizing the combined FBG structure, and decoupling was realized easily.

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A Medium-Frequency Fiber Bragg Grating Accelerometer Based on Flexible Hinges

Sensors ◽

10.3390/s21216968 ◽

2021 ◽

Vol 21 (21) ◽

pp. 6968

Author(s):

Zichuang Li ◽

Lei Liang ◽

Hui Wang ◽

Shu Dai ◽

Ke Jiang ◽

...

Keyword(s):

Resonance Frequency ◽

Fiber Bragg Grating ◽

Temperature Effects ◽

Bragg Grating ◽

Structure Model ◽

Frequency Range ◽

Medium Frequency ◽

Acceleration Sensors ◽

Compensation Function ◽

Sensing Characteristics

Mediumfrequency fiber Bragg grating (FBG) acceleration sensors are used in important applications in mechanical, aerospace and weapon equipment, and have strict requirements in terms of resonance frequency and sensitivity. A novel medium-frequency accelerometer, based on fiber Bragg grating and flexible hinges, is proposed in this paper. The differential structure doubles the sensitivity of the sensor while avoiding temperature effects. The structure model and principle for the sensor are introduced, the sensor’s sensing characteristics are theoretically analyzed, and the structure parameters for the sensor are determined through numerical analysis. The sensing experiments show that the resonance frequency of the sensor is approximately 2800 Hz, the sensitivity is 21.8 pm/g in the flat frequency range of 50–1000 Hz, and the proposed sensor has a good temperature self-compensation function and lateral anti-interference capability.

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Dual-parameter sensing characteristics of a single fiber Bragg grating half-pasted by 1C-LV epoxy under different curing

Optica Applicata ◽

10.37190/oa210307 ◽

2021 ◽

Vol 51 (3) ◽

Author(s):

Hong Li ◽

Haoyue Zhang ◽

Yanming Song ◽

Fanyong Meng ◽

Lianqing Zhu

Keyword(s):

Fiber Bragg Grating ◽

Experimental System ◽

Single Fiber ◽

Bragg Grating ◽

Curing Conditions ◽

Fbg Sensor ◽

Novel Technology ◽

Sensor Structure ◽

Narrow Space ◽

Sensing Characteristics

A novel technology for the simultaneous and independent measurement of dual parameters is proposed and experimented. By using a single fiber Bragg grating half-pasted by 1C-LV epoxy under different curing conditions, the sensor structure is designed such that the reflective single-peak spectrum splits into a twin-peak spectrum, which makes the FBG spectrum form a natural spectral peak splitting bias. A measurement limitation exists in the FBG sensor packaging at room temperature, which can be solved by the high-temperature cured packaging method. To verify the validity of the theory and methodology, the experimental system is used. In the range from –1000 to +1000 με and from 35 to 75°C, the Bragg wavelength change is relative linear to the strain and temperature. The temperature and strain variations can be independently and simultaneously measured using the split peak, and the deviations of the FBG sensor are ±1°C and ±5 με, respectively. This single FBG sensor can realize dual-parameter measurement, which is valuable for narrow-space health monitoring.

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Sensing Characteristics of a Fiber Bragg Grating Hydrogen Gas Sensor using Sol-Gel Derived Pt/WO3 Film

ECS Meeting Abstracts ◽

10.1149/ma2012-02/56/3892 ◽

2012 ◽

Keyword(s):

Fiber Bragg Grating ◽

Gas Sensor ◽

Sol Gel ◽

Hydrogen Gas ◽

Bragg Grating ◽

Sensing Characteristics

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Sensing Characteristics of Sampled Fiber Bragg Grating about Temperature and Strain

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.397-400.1723 ◽

2013 ◽

Vol 397-400 ◽

pp. 1723-1727

Author(s):

Dan Dan Zhu ◽

Yi Ping Wang ◽

Wei Liu ◽

Dan Rui Meng ◽

Xiu Zhen Hu ◽

...

Keyword(s):

Fiber Bragg Grating ◽

Spectral Characteristics ◽

Bragg Grating ◽

Fiber Grating ◽

Strain Sensing ◽

Sensing Data ◽

The People ◽

Sensing Model ◽

Sampled Grating ◽

Sensing Characteristics

Sampled fiber grating is a novel fiber Bragg grating. Because of it is flexible, passive, low insertion loss and small polarization dependent. It causes great interest and enthusiasm of the people in many areas. Ambient temperature and strain can both affect sampled grating reflection spectrum. On the base of analysis of sampled grating temperature and strain sensing model ,we can use computer to simulate the sampled grating temperature and strain sensing experiments to get Sampled grating temperature sensing data and strain sensing data. By analyzing the factors of temperature and strain which affect the spectral characteristics of the sampled grating, and using regression analysis methods to respectively get the 4 parameters A, B, C, D of sensing properties, so we can simultaneously measure the changes of temperature and strain through single sampled grating.

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