摘要
提出并研究了一种新颖的钟摆式光纤光栅(FBG)二维倾斜角传感器,其摆杆顶端采用圆锥结构,两个FBG沿着母线方向并间隔四分之一圆周粘贴在圆锥表面,摆杆下端固定一定质量的重物。在倾斜角发生变化时,圆锥表面产生的沿着母线方向梯度分布的应变场使FBG产生啁啾效应。利用功率谱平坦的宽带光源,通过监测两个FBG的反射光强变化,可实现二维倾斜传感。此外,由于光纤光栅的反射光强不随温度变化,所以该传感器的测量对温度不敏感。实验在±4°范围内测得该传感器的灵敏度为1.96μW/(°),精度为±0.125°。
A novel two-dimensional （2D） tilt sensor was demonstrated by incorporating two fiber Bragg gratings （FBGs） with a deliberately designed pendulum, which was composed of a tapered cylindrical beam and a mass. Two FBGs were glued on the surface of the taped part of the beam at the same height along the generatrix direction and separated by a quarter of the circumference of the beam for each other. When the tilt angle was applied, chirp effect was introduced due to the non-uniform tilt-induced strain field applied along the length of the FBGs. The reflection bandwidths varied linearly with the applied tilt angle, By monitoring the reflected optical powers of the two FBGs with a flattened broadband source and an optical power meter, 2D tilt angle measurement was realized. Furthermore, the measurement was not sensitive to temperature because the reflected optical power was not changed with temperature. In the experiment, a high sensitivity of 1.96 μW/（°） over the tilt range from -4° to 4° was achieved, and the accuracy was ＋0.125°. Benefited from the simple demodulation method and the inherently temperature-insensitivity of the sensing signal, the proposed pendulum clinometer is cost-efficient and independent of temperature.
出处
《红外与激光工程》
EI
CSCD
北大核心
2011年第11期2213-2216,共4页
Infrared and Laser Engineering
基金
国家973计划(2010CB327800)
国家自然科学基金(60807021)
浙江省自然科学基金(R1080087)
关键词
倾斜角传感器
光纤光栅
光纤传感
温度不敏感
tilt sensors
fiber Bragg gratings（FBGs）
optic fiber sensing
temperature-insensitive
