桥式起重机模型挠度的光纤Bragg光栅试验研究

Experiment research on using optical fiber Bragg grating to measure deflection of bridge crane model

研制了1种利用光纤Bragg光栅对桥式起重机主梁挠度的实时在线监测模型。光纤Bragg光栅均匀粘贴于桥式起重机主梁,通过输入输出光纤与信号处理装置光连接。小车在主梁上吊挂后使主梁产生挠度,主梁作用粘贴其下表面的光纤Bragg光栅产生应变,即传感光栅的Bragg波长产生移位。利用解调仪得到的光纤Bragg光栅中心波长的移位值,反复计算挠度值,实现波长与挠度的对应关系。

The paper describes a real-time online monitoring model for deflection of main girder of bridge crane with fiber Bragg grating.The fiber Bragg grating is evenly affixed on the main girder of the bridge crane and optical connection is achieved through input and output optical fiber and signal processor unit.The trolley suspended on the main girder causes deflection,and the main girder causes strain of fiber Bragg grating affixed on its lower surface,that is,displacement of wavelength of sensing Bragg grating.Deflection value is calculated repeatedly with displacement value of central wavelength obtained by demodulator to obtain relation between wavelength and deflection.