基于塑料光纤迈克尔逊干涉的角度传感器

Angle sensor based on plastic optical fiber Michelson interference

光纤角度传感器在工业工程角度测量中具有重要意义。然而,受制于光纤材质和传感器结构设计,当前光纤角度传感器存在测量范围小、受环境温湿度影响、可靠性差等问题。提出一种基于迈克尔逊干的涉塑料光纤(plastic optical fiber,POF)角度传感器。将端面镀膜的POF与单模光纤拼接形成迈克尔逊干涉仪,当POF角度变化时,干涉模式被调制而导致光谱偏移。通过监测干涉光谱波长偏移,即可实现角度测量。实验结果显示,传感器最大角度变化可达480°,并在0°~80°内体现出良好的线性度,灵敏度为25.36 pm/°。由于所选用POF材质为吸水性较弱的氟化聚合物,且通过串接FBG进行温度补偿,显著减小了环境温湿度影响。此外,POF良好的柔韧性保证了传感器的机械强度。上述特点使该传感器在复杂环境下的单端探针式角度测量中体现出较大的应用潜力。

Fiber optic angle sensors are of great significance in industrial engineering angle measurement.However,due to the limitations of fiber optic materials and sensor structure design,current fiber optic angle sensors have problems such as small measurement range,poor reliability,and being affected by environmental temperature and humidity.This article proposes a Michelson interferometric angle sensor based on plastic optical fiber(POF).Splicing the POF coated on the end face with a single mode fiber forms a Michelson interferometer.When the POF angle changes,the interference mode is modulated,resulting in spectral shift.By monitoring the wavelength shift of the interference spectrum,angle measurement can be achieved.The experimental results show that the maximum angle change of the sensor can reach 480°,and it exhibits good linearity within 0~80°,with a sensitivity of 25.36 pm/°.The selected POF material is a fluorinated polymer with weak water absorption,and temperature compensation is achieved by connecting FBG,which significantly reducing the impact of environmental temperature and humidity.In addition,the flexibility of POF ensures the mechanical strength of the sensor.The above characteristics demonstrate great potential for the sensor in single ended angle measurement in complex environments.