微驱动器的压电-弹性耦合分析(英文)

Coupled Analysis on the Piezoelectric-Elastic Micro Actuator

压电弹性耦合结构是实现MEMS微流体驱动的一种重要方式,掌握压电-弹性振动的耦合机理是微流体驱动协调控制的关键。针对压电与硅膜耦合微驱动结构,基于压电效应和弹性薄板理论,采用Rayleigh-Ritz能量法建立了周边固支边界条件下,弹性振动硅膜与压电驱动膜片耦合振动的理论模型,推导并计算了该微驱动结构的耦合振型及谐振频率。基于激光测振仪进行了该压电微驱动结构的振动测试实验,经实验模态分析获得了实测的谐振频率。理论计算结果与实验测试结果的对比分析表明,两者基本相符,验证了理论分析模型的正确性,为MEMS微流体的驱动与控制提供了一定的理论基础和实验依据。

A coupled structure having an elastic vibrating film bonded with a PZT layer is mainly employed as the actuator in MEMS devices. It is a key point of actuating and controlling microfluid to grasp the coupled mechanism of piezoelectric-elastic structure. The displacement field models for such piezoelectric-silicon actuator were established according to the Kirchhoff assumption for thin plates and the piezoelectric effect. Under the boundary condition of clamped edge, the natural frequency and mode shape of such coupled structure were achieved by means of Rayleigh-Ritz energy method. An experimental investigation was carried out to verify the applicability of the analytical model. A good agreement between the theorical and experimental results was observed. The results show that the model can predict natural frequencies and modes shapes of these kinds of coupled structure or actuator accurately. The investigation provides theoretical and experimental foundation for actuating and controlling of micro fluid.