动静态载荷下光纤光栅传感器敏感特性研究

针对航空航天领域板结构动静态载荷监测需求，研究了基于铝合金板结构的光纤光栅（Fiber Bragg grating,FBG）传感器感知特性。从静载监测角度，得到光纤光栅传感器中心波长偏移量与加载距离、载荷大小和加载角度的对应关系。从动载监测角度，分别得到在不同加载距离和不同加载夹角的载荷作用下，光栅中心波长最大峰值幅度和基于小波包分解的能量谱特征随冲击载荷属性变化的响应特性。研究表明在动静态载荷作用下，光纤光栅传感器中心波长偏移量随加载载荷的增大而呈现良好的单调递增关系。此外，光纤光栅传感器还具有较好的载荷 方向敏感特性，传感器响应灵敏度随着加载夹角增大而逐渐提高。这些特性能够为进一步开展基于光纤光栅传感器的板结构动静态载荷辨识与损伤监测提供有益帮助。

Sensitivity of Optical FBG Sensor Under Dynamic/Static Load

For meeting the need of monitoring dynamic/static load of plate structure in the aerospace field, the fiber Bragg grating (FBG) sensing characteristics based on aluminum plate structure are researched. From the perspective of monitoring static load, the relationships between the offset of FBG center wavelength and the loading distance, the loading size and the loading angle are obtained. From the perspective of monitoring dynamic load, under loading with different distance and angles, the response characteristics about the maximum peak amplitude of FBG center wavelength and the eigenvalue of energy spectrum based on wavelet packet decomposition changing with the impact loading are obtained. The results show that under dynamic/static load, FBG center wavelength offset increases with the increase of the load, which shows a good monotone increasing relationship. In addition, FBG shows a good sensitive characteristic of load-direction, and the response sensitivity gradually increases with the increase of loading angle. These features can provide useful help for further study on identifying staticand dynamic load as well as monitoring damage of plate structure based on FBG sensors.