基于模态局部化的可调式压电驱动谐振质量传感器的设计

Design of Tunable Piezoelectric Driven Resonant Mass Sensor Based on Modal Localization

该文提出了一种基于模态局部化现象来检测外部质量扰动的可调式压电驱动谐振质量传感器,质量传感器的检测结构由两个不同长度的悬臂梁通过机械耦合梁连接。首先利用哈密顿原理对压电驱动下的非对称谐振元件进行理论建模,采用伽辽金方法求解,得到前两阶模态下的振动特性;理论求解所得固有频率与COMSOL仿真分析、实验数据基本一致。实验研究表明,无调谐质量的谐振器检测范围为2~10 mg,添加调谐质量后的谐振器检测范围提高至1~13 mg,质量检测的分辨率也得到优化。此外,对传感器的结构进行非线性分析研究发现,超谐振动下的谐振器检测灵敏度提升了80%,这为非线性谐振传感器的设计提供了基础。

A tunable piezoelectric driven resonant mass sensor based on modal localization is proposed to detect the external mass disturbances in this paper. The detection structure of the mass sensor is composed of two cantilever beams with different lengths connected by mechanical coupling beams. Firstly, the theoretical modeling of asymmetric resonant element driven by piezoelectric actuator was carried out by using Hamiltonian principle and solved by Galerkin method. The vibration characteristics of the first two modes were obtained. The natural frequencies obtained by the theoretical solution are basically consistent with the COMSOL simulation analysis and experimental data comparison. Different experimental studies have shown that the detection range of the resonator without tuning mass was 2~10 mg, and the detection range of the resonator with tuning mass was increased to 1~13 mg, and the resolution of quality detection was also optimized. In addition, the nonlinear analysis of the structure of the sensor was carried out, and it was found that the detection sensitivity of the resonator under super harmonic vibration has been improved by 80%, which provided a basis for the design of the nonlinear resonance sensors.