压电质量传感器检测灵敏度分析

Detection sensitivity analysis for piezoelectric mass sensor

压电质量传感器是一种利用压电谐振器对质量的敏感性,通过谐振器吸附待测物后频率的变化实现对被测物质进行检测的传感器。由于附着物质引起的质量变化很小,因此测试精度将强烈依赖于结构频率对质量变化的敏感程度,而敏感程度与传感器感知部分的几何尺寸密切相关。本文主要研究压电材料悬臂梁式质量传感器的检测敏感度分析问题,推导传感器自振频率变化对质量变化的灵敏度与传感器各部分结构几何尺寸设计参数依赖关系的计算格式,并讨论了结构尺寸、截面形状以及谐振模态对传感器检测灵敏度的影响。

A piezoelectric sensor for mass detection is a new type of sensor using piezoelectric materials as transverse transducer. A piezoelectric sensor＇s resonance frequency shift is measured to quantify the small mass attached to the surface. Since the adsorbed mass is very small, the testing accuracy of the pie- zoelectric sensor is strongly depended on the mass detection sensitivity which is defined as the resonance frequency shift with respect to a loaded mass. This paper presents an investigation into the derivation of the relationship between the mass detection sensitivity and the structural configuration parameters. The dependence of mass detection sensitivity on structural configuration parameters and resonance modes is examined through numerical examples.