基于伸缩杆结构的光纤光栅多级应变传感器

Fiber Bragg Grating Multi-level Strain Sensor Based on the Structure of Extendable Rod

为了扩大光纤光栅称重传感器的测量范围,提高传感器的测量精度,在理论上设计了一套新型的可以扩大测量范围、提高测量精度的系统,并通过Matlab平台仿真.结果表明,单级传感器在波长变化小于0.2 nm时具有良好的线性度.该系统将双光纤光栅串联,分别粘贴于等强度梁的上下两侧,采用光强解调的方法实现对光纤光栅输出信号的解调;在解调基础上,利用伸缩杆结构传递载荷重力.实验测试结果验证了多级应变测量的可行性,在保证分辨力的同时扩大了传感器的测量范围.

In order to expand the measurement range of optical fiber grating load cell and improve the measurement accuracy of the sensor,a novel multi-level load cell was designed theoretically and simulated by Matlab. Simulation result showed that the single sensor had good linearity when the fluctuation of wavelength is below 0. 2 nm. In this system,the dual-optical fiber gratings were connected in series with the upper and lower sides of the equal-strength beam. And the output signal of the optical fiber grating was demodulated by the method of light intensity demodulation.By the extendable rod structure,the sensor becomes multi-level sensing,then the measurement range was broadened unchanging its measurement resolution. The feasibility of the proposed sensor was verified by experimental results.