特种微结构光纤振动传感器及其铁路监测应用  

Special Microstructured Optical Fiber Based Vibration Sensor and Its Application in Railway Monitoring

作　　者：刘正勇 LIN Htein 刘繄[4] 钟永康 谭华耀[3] LIU Zhengyong;LIN Htein;LIU Yi;CHUNG Weng-Hong;TAM Hwa-Yaw(School of Electronics and Information Technology,Sun Yat-sen University,Guangzhou 510006;Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai),Zhuhai 519000;Department of Electrical Engineering,The Hong Kong Polytechnic University,Hong Kong 999077;School of Mechanical and Electronic Engineering,Wuhan University of Technology,Wuhan 430205)

机构地区：[1]中山大学电子与信息工程学院,广州510006 [2]南方海洋科学与工程广东省实验室,珠海519000 [3]香港理工大学电机工程学系,中国香港999077 [4]武汉理工大学机电工程学院,武汉430205

出　　处：《机械工程学报》2022年第8期63-70,共8页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(61905096)。

摘　　要：提出基于特种微结构光纤的振动加速度传感器,将高性能的光纤振动传感器应用于铁路结构的健康监测,设计并研制了Sagnac型的振动传感器。通过对光纤结构的合理设计和优化,可以获得高双折射率特性,并能针对外界侧向压力的变化产生对应的相位改变量,进而建立起外界振动引起的动态压力与微结构光纤中传导模式之间的线性关系。基于此原理设计的振动传感器具有较高的加速度灵敏度,以及较宽的频率响应,灵敏度高于25pm/g,其实际谐振频率高于2500Hz,并与传感器机械结构封装有关。通过对铁路运营列车的实时监测,所提出的新型微结构光纤振动传感器可以准确获得低频范围内的大幅振动信息,并可较好的反映出高频扰动,有助于实时监测钢轨波纹形变。所提出的新型六孔微结构光纤振动传感器对于铁路、桥梁及机械等结构的振动实时监测提供了新思路和方法,具有很大的应用前景。In this paper,a special microstructured optical fiber based vibration sensor is proposed and experimentally employed in the structural health monitoring of railway.To achieve this,the vibration sensor based on Sagnac interferometer was designed and fabricated.By optimizing the structure of the microstructured optical fiber that has six air holes in the cladding,it could possess high birefringence that changes with the external force applying to the fiber laterally,based on which a linear relationship between the dynamic force and the propagating mode guided in the fiber could be established.Such vibration sensor exhibits a sensitivity of 25 pm/g to acceleration as well as a broad response frequency range.Its resonant frequency is up to over 2 500 Hz,which is dependent on the mechanical design of the sensor package.A field test was conducted using the proposed vibration sensor,and the sensor could measure the large amplitude vibration in low frequency range,as well as those vibrations in high frequency range,which is helpful to identify the corrugations on the rail.The proposed novel vibration sensor based on six-hole microstructured optical fiber provides a new pathway or approach for monitoring the vibration of structures in railway,bridge and mechanical engineering,showing great potential in the applications.

关 键 词：微结构光纤 振动传感器 加速度 结构健康监测 

分 类 号：TN253[电子电信—物理电子学]