基于多光谱和复阻抗的复合结冰探测技术

Integrated ice detection technology based on multispectral and complex impedance principles

针对基于光强调制的光纤结冰传感器容易受污染物干扰的问题,提出了一种基于多光谱和复阻抗原理的复合式结冰探测技术,并通过实验对该方法进行了评估。根据待识别污染物的类型,多光谱和复阻抗传感器分别采集了具有区分性的4个近红外波段以及4个频率点数据。通过对每种不同类型表面状态提取21维多光谱特征和15维复阻抗特征,结合主成分分析及支撑向量机算法,建立了对明冰、积水表面状态的识别方法。实验结果表明,该方法可以排除防冻液、沙尘等5种常见的污染物干扰,在3010条数据中实现了99.6%的状态识别准确率。对于明冰、积水的情况,进一步分析了液态水结冰过程的探测结果以及两种传感器的冰厚测量特性。实验结果表明940 nm波段的电压信号以及频率点为1.5 kHz的复阻抗等效电容值,能够表征结冰的相变过程并与冰厚具有明显相关性。

Optical fiber ice sensors based on light intensity modulation are susceptible to contaminant interference.To solve this problem,an integrated ice detection technique is proposed based on multispectral and impedance principles,and the technique is evaluated by experiments.Depending on the types of contaminants to be identified,the data of the multi-spectral and impedance sensor in four distinguishable near-infrared bands and four frequency points are collected respectively.By extracting 21-dimensional multispectral features and 15-dimensional complex impedance features for each different type of surface state,a method for recognizing the surface state of glazed ice and water is established by using principal component analysis and support vector machine algorithms.The experimental results show that the method can exclude the interference of five common pollutants,such as antifreeze and sand,and achieve 99.6%state recognition accuracy in 3010 data.For the case of glazed ice and water,the detection results of the liquid water icing process and the characteristics of the two sensors for measuring ice thickness are further analyzed.The experimental results also show that the voltage signal in the 940 nm band and the impedance equivalent capacitance value at the frequency point of 1.5 kHz can characterize the phase change process of icing and correlate significantly with ice thickness.