基于正交的声表面波应变传感器的温度应变解耦方法  

Temperature Strain Decoupling Method Based on Orthogonal Surface Acoustic Wave Strain Sensor

作　　者：李向荣 秦丽[1] 谭秋林[1] LI Xiang-rong;QIN Li;TAN Qiu-lin(North University of China,State Key Laboratory of Dynamic Measurement Technology,Taiyuan 030051,China;College of Science,North University of China,Taiyuan 030051,China)

机构地区：[1]中北大学,省部共建动态测试技术国家重点实验室,山西太原030051 [2]中北大学理学院,山西太原030051

出　　处：《仪表技术与传感器》2022年第9期122-126,共5页Instrument Technique and Sensor

基　　金：国家自然科学基金(U1837219)。

摘　　要：针对应变测量的温度干扰问题,文中设计了2个声表面波应变传感器,2个传感器的频率分别为240.856 MHz和239.22 MHz。2个传感器粘贴在悬臂梁上靠近固定端的2个位置,一个沿着声表面的传播方向与应变方向一致的方向粘贴,另一个沿着传播方向与应变垂直的方向粘贴。然后对传感器的温度应变响应进行测试,测得了传感器芯片在25~200℃下的频率响应。结果表明一个谐振器的共振频率随着应变的增加而减小,频率与应变为线性关系,室温下灵敏度为192.5 Hz/με。另一个谐振器的共振频率随着应变的增加而增加,频率与应变为线性关系,室温下灵敏度为128.7 Hz/με。然后提取出不同温度下的应变灵敏度,2个传感器的灵敏度随着温度的变化,先增加后减小。然后将2个传感器频率做差,通过计算实现了应变精确值的提取。In order to solve the temperature interference problem of strain measurement,two surface acoustic wave strain sensors were designed in this paper,and the frequency of the two sensors were 240.856 MHz and 239.22 MHz respectively.The two sensors were pasted in two positions near the fixed end of the cantilever beam.One was pasted along the direction in which the propagation direction of the sound surface was consistent with the strain direction,and the other was pasted along the direction in which the propagation direction was perpendicular to the strain direction.Then,the temperature strain response of the sensor was tested on the strain-temperature composite test platform,and the frequency response of the sensor chip was measured at 25~200℃.The results show that the resonant frequency of a resonator decreases with the increase of strain,the frequency is linear with strain,and the sensitivity is 192.5 Hz/μεat room temperature.The resonance frequency of the other resonator increases with the increase of strain,and the frequency is linear to strain,with a sensitivity of 128.7 Hz/μεat room temperature.Then the strain sensitivities at different temperatures are extracted.The sensitivities of the two sensors increase first and then decrease with the change of temperature.Then the frequency difference between the two sensors is made,and the exact strain value can be extracted by calculation.

关 键 词：声表面波 应变传感器 解耦 LiNbO_(3) 应变灵敏度 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]