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Monitoring shear deformation of sliding zone via fiber Bragg grating and particle image velocimetry
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作者 Deyang Wang Honghu Zhu +3 位作者 Guyu Zhou Wenzhao Yu Baojun Wang Wanhuan Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期231-241,共11页
Monitoring shear deformation of sliding zones is of great significance for understanding the landslide evolution mechanism,in which fiber optic strain sensing has shown great potential.However,the cor-relation between... Monitoring shear deformation of sliding zones is of great significance for understanding the landslide evolution mechanism,in which fiber optic strain sensing has shown great potential.However,the cor-relation between strain measurements of quasi-distributed fiber Bragg grating(FBG)sensing arrays and shear displacements of surrounding soil remains elusive.In this study,a direct shear model test was conducted to simulate the shear deformation of sliding zones,in which the soil internal deformation was captured using FBG strain sensors and the soil surface deformation was measured by particle image velocimetry(PIV).The test results show that there were two main slip surfaces and two secondary ones,developing a spindle-shaped shear band in the soil.The formation of the shear band was successfully captured by FBG sensors.A sinusoidal model was proposed to describe the fiber optic cable deformation behavior.On this basis,the shear displacements and shear band widths were calculated by using strain measurements.This work provides important insight into the deduction of soil shear deformation using soil-embedded FBG strain sensors. 展开更多
关键词 LANDSLIDE Shear band fiber bragg grating(fbg) Particle image velocimetry(PIV) Sinusoidal model Strain‒displacement proportional COEFFICIENT
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Perimeter Security System Based on Ultra-Weak Fiber Bragg Grating Array
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作者 Zhihui Luo Hao Xiang +1 位作者 Yu Zhang Bing Xu 《Optics and Photonics Journal》 2022年第6期156-169,共14页
A perimeter security system based on ultra-weak fiber Bragg grating high-speed wavelength demodulation was proposed. The demodulation system for signal acquisition and high-speed wavelength calculation was designed ba... A perimeter security system based on ultra-weak fiber Bragg grating high-speed wavelength demodulation was proposed. The demodulation system for signal acquisition and high-speed wavelength calculation was designed based on field programmable gate array (FPGA) platform. The principle of ultra-weak fiber Bragg grating high-speed demodulation and signal recognition method were analyzed theoretically, and the Support Vector Machine model was introduced to optimize the event recognition accuracy of the system. A perimeter security experimental system containing 1000 ultra-weak fiber Bragg gratings, ultra-weak fiber Bragg grating sense optical cables with a diameter of 2.0 mm and a reflectivity of 0.01%, steel space frames and demodulation equipments was built to recognize four typical events such as knocking, shaking, wind blowing and rainfall. The experimental resulted show that the system has a spatial resolution of 1m and an acquisition frequency of 200 Hz. The joint time-frequency domain detection method is used to achieve 99.2% alarm accuracy, and 98% recognition accuracy of two intrusion events, which has good anti-interference performance. 展开更多
关键词 perimeter Security Ultra-Weak fiber bragg grating Vibration Sensor Pattern Recognition
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基于正弦式波纹膜片的压差式FBG静力水准仪
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作者 朱万旭 吴尧 +2 位作者 黄家柱 李梦果 刘丰荣 《传感器与微系统》 CSCD 北大核心 2024年第5期109-112,共4页
为解决建筑物不均匀沉降长期、可靠监测的问题,基于连通器原理,推导了膜片半径r、刚度K、光纤自由段长度l、波长变化量Δλ_(B)等参数和沉降量的线性关系式。以此设计了带有正弦式波纹膜片的压差式光纤布拉格光栅(FBG)静力水准仪,并通... 为解决建筑物不均匀沉降长期、可靠监测的问题,基于连通器原理,推导了膜片半径r、刚度K、光纤自由段长度l、波长变化量Δλ_(B)等参数和沉降量的线性关系式。以此设计了带有正弦式波纹膜片的压差式光纤布拉格光栅(FBG)静力水准仪,并通过标定试验验证压差式FBG静力水准仪的传感性能。结果表明:此静力水准仪灵敏度不小于13.2 pm/mm,综合误差不大于3.26%,相关性系数均在0.99以上。该型静力水准仪传感性能满足工程结构沉降测量的要求,丰富了FBG静力水准仪的研究,具有理论和现实意义。 展开更多
关键词 静力水准仪 光纤布拉格光栅 不均匀沉降 标定试验 传感器
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基于应变增敏的双层十字型FBG触觉感知单元
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作者 孙世政 何江 +2 位作者 秦鸿宇 徐向阳 陈仁祥 《光学精密工程》 EI CAS CSCD 北大核心 2024年第17期2718-2731,共14页
触觉感知是仿生智能感知的重要内容,为了提高光纤布拉格光栅(Fiber Bragg Grating, FBG)触觉感知灵敏度,结合机器手指尖触觉感知需求,提出了一种应变增敏的FBG触觉感知单元。基于应变增敏机理和触觉感知机理分析,设计了一种基于应变增... 触觉感知是仿生智能感知的重要内容,为了提高光纤布拉格光栅(Fiber Bragg Grating, FBG)触觉感知灵敏度,结合机器手指尖触觉感知需求,提出了一种应变增敏的FBG触觉感知单元。基于应变增敏机理和触觉感知机理分析,设计了一种基于应变增敏的双层十字型FBG触觉感知单元,采用刚性球型多点增压结构进行应变增敏。利用仿真分析方法优化了FBG空间分布,并对感知单元进行了静力学和热力学仿真。最后搭建了触觉感知实验平台,结合机器手完成了温度-力触觉协同感知实验。仿真和实验结果表明,FBG1和FBG2的力触觉感知灵敏度分别为18.069 nm/MPa和1.065 nm/MPa,温度感知灵敏度为11.256 pm/℃和11.153 pm/℃。该触觉感知单元有效提高了触觉感知灵敏度,具有良好的线性度和重复性。 展开更多
关键词 光纤传感 光纤布拉格光栅 应变增敏 双层十字型 触觉感知单元
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FBG反射谱数据滑动相关滤波算法设计与实现
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作者 马嘉仪 张旭 +2 位作者 李红 朱云鸿 董明利 《红外与激光工程》 EI CSCD 北大核心 2024年第6期146-158,共13页
针对光纤光栅解调系统中现有滤波算法计算速度与滤波效果难以兼顾的问题,提出了一种基于滑动相关滤波的光纤布拉格光栅(Fiber Bragg Grating,FBG)反射谱滤波方法并在现场可编程门阵列(Field Programmable Gate Array,FPGA)上实现算法加... 针对光纤光栅解调系统中现有滤波算法计算速度与滤波效果难以兼顾的问题,提出了一种基于滑动相关滤波的光纤布拉格光栅(Fiber Bragg Grating,FBG)反射谱滤波方法并在现场可编程门阵列(Field Programmable Gate Array,FPGA)上实现算法加速设计。该算法根据FBG半峰全宽确定高斯函数二阶导数的标准差,用函数的负数作为滤波模板权重,通过滑动数据窗口进行反射谱数据与滤波模板的相关计算,从而实现滤波操作。使用该算法处理含高斯噪声、坏点和基线的仿真数据,验证了该方法对多种异常反射谱数据处理的有效性,并与其他下位机滤波算法进行对比分析,该算法能较好地保留原始数据特征,有较好的鲁棒性,信噪比最高提升28.23dB,中心波长平均偏差和偏差标准差最小,分别为1.712 pm和2.996pm。同时在FPGA片上平台实现了该算法,采用循环队列策略设计存储器,提高了存储器使用率,降低了资源消耗。实验表明,该算法可以有效校正多种异常FBG反射谱,在100MHz系统时钟下处理一个反射谱数据所需时间仅5.09μs,易于实现工程化应用,克服了下位机现有滤波算法对FBG反射谱中坏点、基线抑制作用较差和滤波后信号变形的问题,实现了FBG反射谱滑动相关滤波算法的加速设计。 展开更多
关键词 滑动相关滤波 光纤光栅传感 fbg滤波 FPGA
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Study on rock deformation monitoring using fiber Bragg grating in simulation experiment 被引量:4
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作者 柴敬 魏世明 刘金瑄 《Journal of Coal Science & Engineering(China)》 2006年第2期30-33,共4页
Presented the fiber Bragg grating (FBG) sensors for rock strain monitoring in the 1.2 m long plane stress model of the simulation experiment. In the past, for the lack of appropriate technique to measure the deforma... Presented the fiber Bragg grating (FBG) sensors for rock strain monitoring in the 1.2 m long plane stress model of the simulation experiment. In the past, for the lack of appropriate technique to measure the deformation of rock structures, the measurement of deflection was restricted to just a few discrete points along rock, and the measuring points were limited to the location installed with displacement transducers. We developed a method to monitor the deformation of rock structures using fiber optical Bragg grating strain sensors. The sensors were embedded in rock layers of simulation experiment before the materials were put in. These sensors were then used to monitor the experienced strain with different face advancing distance. The test results indicate that, if properly installed, FBG sensors can survive under severe conditions associated with embedment process and yield accurate measurements of strains response. At the same time, we make comparisons of the data obtained by FBG sensors with those by centesimal gauge. The interest in FBG sensors was motivated by the potential advantages that they can offer more than existing sensing technologies. 展开更多
关键词 fiber bragg grating (fbg simulation experiment rock layers SENSORS STRAIN
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Resistance Spot Welding Method for Metal-Based Fiber Bragg Grating Sensors 被引量:1
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作者 张涛 韦朋余 岳亚霖 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第3期289-296,共8页
Aiming at the requirements of installation and work environment of metal-based fiber Bragg grating(FBG)sensor,a resistance spot welding method is presented.Firstly,the effect of welding parameters on welding quality i... Aiming at the requirements of installation and work environment of metal-based fiber Bragg grating(FBG)sensor,a resistance spot welding method is presented.Firstly,the effect of welding parameters on welding quality is discussed theoretically,and a suitable resistance spot welding method for the metal-based FBG sensor is proposed for the first time.Then through serial resistance spot welding tests,the feasibility and practicability of the method are verified,and optimal welding parameters for two different tested metals are obtained.Fatigue performance test validates FBG sensors installed by the proposed method with good fatigue properties and long-term stable measurement performance.The research results can provide technical guidance for engineering structure long-term safety monitoring. 展开更多
关键词 fiber bragg grating(fbg)sensor resistance SPOT wel
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An active temperature compensated fiber Bragg grating vibration sensor for high-temperature application 被引量:2
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作者 CHEN Bao-jie JIA Ping-gang +4 位作者 QIAN Jiang FENG Fei HONG Ying-ping LIU Wen-yi XIONG Ji-jun 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第4期397-404,共8页
An active temperature compensated fiber Bragg grating(FBG)vibration sensor with a constant section cantilever beam is proposed for the simultaneous measurement of temperature and vibration,and the sensor is verified b... An active temperature compensated fiber Bragg grating(FBG)vibration sensor with a constant section cantilever beam is proposed for the simultaneous measurement of temperature and vibration,and the sensor is verified by a temperature compensation feedback system.The high-temperature vibration sensor is composed of a quartz cantilever beam and a femtosecond Bragg grating.The feedback control demodulation system of active temperature compensation can adjust the laser wavelength to stabilize the grating offset point and realize simultaneous measurement of temperature and vibration.On this basis,the performance of the sensor is tested and analyzed within the range of 20-400℃by setting up a high-temperature vibration test system.The experimental results show that the sensitivity of the sensor is about 132.33 mV/g,and the nonlinearity is about 3.33%.The sensitivity between the laser wavelength and temperature is about 0.01307 nm/℃.In addition,the active temperature compensated fiber Bragg grating vibration sensor has the advantages of a simple structure,stable performance,easy demodulation and high sensitivity.Moreover,the sensor can achieve high temperature vibration signal monitoring and has good practical application value. 展开更多
关键词 fiber bragg grating(fbg) vibration sensor active temperature compensation cantilever beam feedback control
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表贴式矿用FBG传感器应力传感特性分析研究 被引量:1
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作者 马仲甜 李钊枢 +3 位作者 万嘉颖 路宁 刘新宇 周脉勇 《传感器与微系统》 CSCD 北大核心 2024年第5期15-18,共4页
本文重点对表贴式矿用光纤布拉格光栅(FBG)传感器应力传感特性进行了分析研究,针对表贴式FBG传感器应力传感特性受基体剪切模量进行系统性的分析,建立表贴式FBG应变三层结构理论分析模型,推导表贴式FBG的应变传递数学表达式,从基体的剪... 本文重点对表贴式矿用光纤布拉格光栅(FBG)传感器应力传感特性进行了分析研究,针对表贴式FBG传感器应力传感特性受基体剪切模量进行系统性的分析,建立表贴式FBG应变三层结构理论分析模型,推导表贴式FBG的应变传递数学表达式,从基体的剪切模量角度分析矿用FBG传感器应力传感特性。通过试验分析总结,得出铜基体材料应变和波长线性关系最佳,可达99.89%,表贴式FBG基体剪切模量越大,应力与波长线性度越好,为矿用FBG传感器结构设计和灵敏度优化提供理论研究基础。 展开更多
关键词 矿用光纤布拉格光栅传感器 剪切模量 应力传感特性
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Fiber Bragg Grating Based Sensing'Platform for Foot Plantar Pressure Measurement 被引量:1
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作者 张一帆 洪成雨 +3 位作者 张佩华 AHMED Zamir 徐建昌 张素青 《Journal of Donghua University(English Edition)》 EI CAS 2017年第6期730-735,共6页
presented an application of using 3 D printing technique for the design and fabrication of a novel fiber Bragg grating( FBG)based sensing platform for foot planar pressure measurement.Pressure sensing unit was fabrica... presented an application of using 3 D printing technique for the design and fabrication of a novel fiber Bragg grating( FBG)based sensing platform for foot planar pressure measurement.Pressure sensing unit was fabricated using 3 D printing technique by layering of extruded polylactic acid( PLA) material and mounting FBG sensor at the center of each sensing unit for pressure measurement. Performance of the sensing system was validated by applying load step by step as well as cyclic load on FBG pressure sensors. A simulation study was carried out using the sensing platform to assess foot plantar pressure distribution arises from weight gaining and losing processes of pregnant woman. The monitored four different foot positions such as first metatarsus,second metatarsus,mid-foot and heel exhibited obvious differences during testing process. Foot plantar pressure of heel was 1. 7 times of the pressure occurred at the first and second metatarsus( fore-foot),while there was limited pressure occurred at the mid-foot position during weight gaining process of a female subject. The occurred pressures at the two metatarsus areas were around 90%( pressure ratio) of heel and decreased continuously as the increase of subject weight,but weight losing process had very limited influence on this pressure ratio. Center of gravity of pregnant woman was found to shift backward substantially during the weighting gaining process,leading to a significant rise of the heel pressure. Hence, the protection of the heel position for female is highly important during both pregnancy and after baby delivery. 展开更多
关键词 3D printing technique fiber bragg grating(fbg) monitoring foot planar pressure pregnant women
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基于FBG的农业大棚土壤温度测量与研究
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作者 钱蔡华 冯飞 +1 位作者 赵恒 李国利 《自动化与仪表》 2024年第1期121-124,129,共5页
研究农业大棚土壤温度,对农业生产具有重要意义。针对传统热电偶等传感器测量土壤温度场存在效率低、误差大等问题,该文采用一种基于光纤布拉格光栅(FBG)的温度传感器来监测农业大棚内的土壤温度变化。该方法将封装了FBG串的不锈钢管垂... 研究农业大棚土壤温度,对农业生产具有重要意义。针对传统热电偶等传感器测量土壤温度场存在效率低、误差大等问题,该文采用一种基于光纤布拉格光栅(FBG)的温度传感器来监测农业大棚内的土壤温度变化。该方法将封装了FBG串的不锈钢管垂直埋入被测土壤中,采用可调谐激光器法和寻峰算法解调FBG串各传感器波长,在大棚环境下进行了土壤多层温度场测量实验。实验结果表明,土壤内部温度呈余弦函数模型周期性变化。随着土壤深度增加,温度变化逐渐减小,在一定的湿度范围内,土壤湿度越大,浅层土壤温度越低。土壤湿度对深层土壤温度影响较小,太阳辐射对浅层土壤温度影响较大。 展开更多
关键词 光纤布拉格光栅 传感器阵列 温度场
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Interrogating a Fiber Bragg Grating Vibration Sensor by Narrow Line Width Light 被引量:5
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作者 Jun Chang Dian-Heng Huo Liang-Zhu Ma Xiao-Hui Liu Tong-Yu Liu Chang Wang 《Journal of Electronic Science and Technology of China》 2008年第4期486-488,共3页
A method to interrogate fiber Bragg grating vibration sensor by narrow line width light is demonstrated. The interrogation scheme takes advantage of the intensity modulation of narrow spectral bandwidth light, such as... A method to interrogate fiber Bragg grating vibration sensor by narrow line width light is demonstrated. The interrogation scheme takes advantage of the intensity modulation of narrow spectral bandwidth light, such as distributed feedback laser, when a reflection or transmission spectrum curve of an fiber Bragg grating (FBG) moves due to the strain which is applied on the sensor. The sensor's response to accelerating frequency and amplitude is measured by experiment. The factors which have impacts on the sensitivity of the interrogation system are also discussed. 展开更多
关键词 fiber bragg grating (fbg interrogation fiber bragg grating sensor optical fiber vibration sensor.
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Fiber Bragg Grating Sensor Array System Based on Digital Phase Generated Carrier Demodulation and Reference Compensation Method 被引量:2
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作者 Jun He Fang Li Hao Xiao Yu-Liang Liu 《Journal of Electronic Science and Technology of China》 2008年第4期389-392,共4页
A novel fiber Bragg grating (FBG) sensor array system based on digital phase generated carrier (PGC) demodulation and reference compensation method is proposed and set up. Experimental results confirm that the dig... A novel fiber Bragg grating (FBG) sensor array system based on digital phase generated carrier (PGC) demodulation and reference compensation method is proposed and set up. Experimental results confirm that the digital PGC demodulation can be used for wavelength-division-multiplexed FBG sensor array and the reference compensation method can reduce the environmental interference by approximately 40 dB in the frequency range from 20 Hz to 2 kHz. The minimum detectable wavelength-shift of the sensor system is 1 × 10^-3 pm/Hz^1/2. 展开更多
关键词 fiber bragg grating (fbg sensor phase generated carrier (PGC) reference compensation method wavelength division multiplexing.
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Hollow and filled fiber bragg gratings in nano-bore optical fibers
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作者 Yong-Xin Zhang Sheng Liang +9 位作者 Qian-Qing Yu Zheng-Gang Lian Zi-Nian Dong Xuan Wang Yu-Qin Lin Yu-Qi Zou Kun Xing Liu-Yan Liang Xiao-Ting Zhao Li-Jing Tu 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期279-285,共7页
To combine the technical functions and advantages of solid-core fiber Bragg gratings(FBGs) and hollow-core optical fibers(HCFs), the hollow and filled FBGs in nano-bore optical fibers(NBFs) with nano-bore in the GeO2-... To combine the technical functions and advantages of solid-core fiber Bragg gratings(FBGs) and hollow-core optical fibers(HCFs), the hollow and filled FBGs in nano-bore optical fibers(NBFs) with nano-bore in the GeO2-doped core are proposed.The fundamental mode field, effective mode index, and confinement loss of NBF with 50 nm–7 μm-diameter hollow and filled nano-bore are numerically investigated by the finite element method.The reflected spectra of FBGs in NBFs are obtained by the transmission matrix method.The hollow FBGs in NBFs can be acheived with ~5% power fraction in the bore and the ~0.9 reflectivity when bore diameter is less than 3 μm.The filled FBGs can be realized with^1% power fraction and 0.98 reflectivity with different fillings including o-xylene, trichloroethylene, and chloroform for 800-nm bore diameter.The feasibility of the index sensing by our proposed NBF FBG is also analyzed and discussed.The experimental fabrication of hollow and filled FBGs are discussed and can be achieved by current techniques.The aim of this work is to establish a principle prototype for investigating the HCFs and solid-core FBGs-based fiber-optic platforms,which are useful for applications such as the simultaneous chemical and physical sensing at the same position. 展开更多
关键词 nano-bore OPTICAL fiber fiber bragg grating(fbg) hollow-core OPTICAL fiber(HCF) fiber optics
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FBG技术监测分析机场跑道沥青加铺层反射裂缝扩展过程
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作者 韦定兵 解建光 +1 位作者 刘燕平 赵勇 《中国民航大学学报》 CAS 2024年第3期69-76,83,共9页
反射裂缝是导致机场跑道加铺层失效的主要病害之一。为分析机场水泥跑道沥青加铺层反射裂缝扩展过程,本文基于光纤布拉格光栅(FBG,fiber Bragg grating)传感技术,提出了可用于实时监测机场水泥跑道沥青加铺层反射裂缝扩展过程的柔性FBG... 反射裂缝是导致机场跑道加铺层失效的主要病害之一。为分析机场水泥跑道沥青加铺层反射裂缝扩展过程,本文基于光纤布拉格光栅(FBG,fiber Bragg grating)传感技术,提出了可用于实时监测机场水泥跑道沥青加铺层反射裂缝扩展过程的柔性FBG传感器封装方法,并对研发的FBG传感器进行了标定。基于室内组合梁试验,分析了机场水泥跑道沥青加铺层复合结构反射裂缝扩展过程,包括微裂纹萌生与积累、反射裂缝扩展、反射裂缝贯通3个阶段。在反射裂缝扩展初期,FBG传感器中心波长增长速率相对较小;随着反射裂缝逐渐扩展,FBG传感器中心波长迅速增大。结果表明,柔性FBG传感器全部存活且性能完整,验证了其在实时监测机场水泥跑道沥青加铺层反射裂缝扩展过程中的可行性。 展开更多
关键词 机场跑道加铺层 反射裂缝 光纤布拉格光栅(fbg fiber bragg grating)传感器 实时监测
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双膜结构FBG土压力传感器优化设计及灵敏度分析
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作者 邢广志 陈博智 吴文婧 《应用科学学报》 CAS CSCD 北大核心 2024年第2期248-261,共14页
为实现桩基础结构安全及其服役状态的监测和有效评估,提出一种双膜结构土压力传感器,以光纤布拉格光栅(fiber Bragg grating,FBG)为传感元件,通过保护结构中增加的温度补偿膜,实现温度作用与外部荷载作用的彻底分离。基于双膜结构土压... 为实现桩基础结构安全及其服役状态的监测和有效评估,提出一种双膜结构土压力传感器,以光纤布拉格光栅(fiber Bragg grating,FBG)为传感元件,通过保护结构中增加的温度补偿膜,实现温度作用与外部荷载作用的彻底分离。基于双膜结构土压力传感器的工作原理,讨论了传感器压力灵敏度系数特性。结合有限元分析和实验研究,对灵敏度系数的影响参数展开了系统分析。数值分析结果表明,膜片厚度对压力敏感度系数的影响最大,结构半径和膜片厚度可选取为20 mm和1.8 mm;实验结果表明,在0-2 MPa范围内,压力灵敏度系数达3.32 pm/kPa。 展开更多
关键词 光纤布拉格光栅 双膜结构 土压力传感器 灵敏度分析
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基于锁模激光器的FBG电流传感器高速解调系统
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作者 王华 何群 +5 位作者 谭如超 武冬 方一诺 马跃辉 严开全 牟成博 《应用科学学报》 CAS CSCD 北大核心 2024年第6期903-911,共9页
智能电网可靠、安全、经济、高效的发展目标,对电流参数的检测速率提出了更高的需求。本文开展了锁模激光器对基于磁致伸缩效应的光纤布拉格光栅(fiber Bragg grating, FBG)电流传感器复用实现高速解调的实验研究,首次将时间拉伸-色散... 智能电网可靠、安全、经济、高效的发展目标,对电流参数的检测速率提出了更高的需求。本文开展了锁模激光器对基于磁致伸缩效应的光纤布拉格光栅(fiber Bragg grating, FBG)电流传感器复用实现高速解调的实验研究,首次将时间拉伸-色散傅里叶变换(time-stretch dispersive Fourier transformation, TS-DFT)技术与光纤电流传感技术进行了结合。固定于磁致伸缩材料表面的FBG能够感知通电螺线管产生的磁场所引发的材料应变。TS-DFT技术可将应力引起的FBG波长偏移映射为时域上反射脉冲的时延偏移实现高速解调。在0~4.5 A电流范围内对2个传感FBG的波长复用进行监测,系统的解调速率高达69.6 MHz,该技术在电流或磁场传感领域有广阔的应用前景。 展开更多
关键词 锁模激光器 时间拉伸-色散傅里叶变换 磁致伸缩效应 光纤布拉格光栅 光纤电流传感器
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Time Division Multiplexing Fiber Bragg Grating Sensor System Using Composite Codes
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作者 CAO Yaoyu XU Hongxuan +3 位作者 ZHANG Yang ZHU Yushuang GUI Lin ZUO Jiancun 《Journal of Donghua University(English Edition)》 EI CAS 2019年第2期163-169,共7页
A novel multi-point sensing scheme to improve the signal-to-noise ratio(SNR),temperature measurement range of the fiber Bragg grating(FBG)sensors is proposed.The new sensing scheme adopted a composite coding technique... A novel multi-point sensing scheme to improve the signal-to-noise ratio(SNR),temperature measurement range of the fiber Bragg grating(FBG)sensors is proposed.The new sensing scheme adopted a composite coding technique based on Simplex codes and Golay codes and time division multiplexing technique to enhance the performance of the sensing system.Simulation results,in good agreement with the theory,confirmed that the maximum SNR enhancement of the sensor system employing composite coding based on 15-bit Simplex codes and 16-bit Golay codes was approximately 6.01 dB in comparison to the conventional single pulse case. 展开更多
关键词 fiber bragg grating(fbg) time division multiplexing(TDM) COMPOSITE CODING scheme CODING gain
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准分布式FBG钢绞线传感性能分析与RPC梁变形监测试验研究
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作者 沈全喜 曹阳 +3 位作者 熊城洋 黄家柱 刘榕 朱万旭 《压电与声光》 CAS 北大核心 2024年第5期801-812,共12页
针对预应力混凝土结构预应力筋受力状态的监测难题,提出了凹槽预压封装准分布式FBG技术,解决了FBG存活率低和监测量程不够的技术难题。通过循环张拉试验和预应力RPC梁加载试验,探究了准分布式FBG钢绞线的传感性能及其对混凝土结构应力... 针对预应力混凝土结构预应力筋受力状态的监测难题,提出了凹槽预压封装准分布式FBG技术,解决了FBG存活率低和监测量程不够的技术难题。通过循环张拉试验和预应力RPC梁加载试验,探究了准分布式FBG钢绞线的传感性能及其对混凝土结构应力状态的监测效果。结果表明,FBG存活率为100%,应变灵敏度为0.00118~0.00120 nm/με,应变传递率β≥0.98,线性度≤2.096%,回差≤1.043%,重复性≤3.615%,总不确定度≤3.881%。准分布式FBG钢绞线可准确识别RPC梁的损伤过程,45%f_(ptk)、65%f_(ptk)、75%f_(ptk)(f_(ptk)为钢绞线极限强度)预应力RPC梁的开裂荷载分别为100 kN、130 kN、140 kN,纵筋屈服荷载分别为260 kN、280 kN、300 kN。RPC梁挠度和钢绞线应变为抛物线型分布,最大挠度分别为27.691 mm、20.153 mm、14.602 mm,最大应变分别为4163.025με、3715.126με、1658.487με。准分布式FBG为预应力结构的整体监测提供了思路。 展开更多
关键词 准分布式光纤光栅传感器 fbg钢绞线 传感性能 预应力监测 预应力RPC梁
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Modified simulated annealing evolutionary algorithm for fully distributed fiber Bragg grating temperature sensing
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作者 陈娜 李承林 +4 位作者 陈振宜 庞拂飞 曾祥龙 孙晓岚 王廷云 《Journal of Shanghai University(English Edition)》 CAS 2011年第1期58-62,共5页
In this paper, we present a simple and fast spectra inversion method to reconstruct the temperature distribution along single fiber Bragg grating (FBC) temperature sensor. This is a fully distributed sensing method ... In this paper, we present a simple and fast spectra inversion method to reconstruct the temperature distribution along single fiber Bragg grating (FBC) temperature sensor. This is a fully distributed sensing method based on the simulated annealing evolutionary (SAE) algorithm. Several modifications are made to improve the algorithm efficiency, including choosing the most superior chromosome, setting up the boundary of every gene according to the density of resonance peaks of the reflection spectrum, and dynamically modifying the boundary with the algorithm running. Numerical simulation results show that both the convergence rate and the fluctuation are significantly improved. A high spat-ial temperature resolution of 0.25 mm has been achieved at the time cost of 86 s. 展开更多
关键词 fiber bragg grating (fbg spectrum inversion algorithm fully distributed temperature sensing
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