MEMS悬臂梁的静态力学模型研究

研究分析了MEMS悬臂梁的静态力学特性。对比分析了集总式静力学模型和枢纽式静力学模型。对于集总式静力学模型,将MEMS悬臂梁的下拉位移假设为处处相等的普通电容极板,得到悬臂梁下拉位移和下拉电压。对于枢纽式静力学模型,将MEMS悬臂梁假设为下拉位移处处不等的转轴,通过寻找悬臂梁在下拉过程中的等效受力点,得到下拉位移和下拉电压。比较了两种模型的静电力学下拉位移与下拉电压的相对误差。结果表明,集总式静力学模型的误差为20.5%,枢纽式静力学模型的误差仅有5.3%。这表明,枢纽式静力学模型的特性优于集总式静力学模型。

Study on Static Mechanical Model of MEMS Cantilever Beam

The static mechanical characteristics of the MEMS cantilever was studied and analyzed. The lumped static model and the pivotal static model were compared. For the lumped static model, the pull-in displacement of the MEMS cantilever beam was assumed to be equal everywhere as a common capacitive electrode plate, and the pull-in displacement and the pull-in voltage of cantilever beam were obtained. For the pivotal static model, the MEMS cantilever beam was assumed to be a rotating shaft with unequal pull-in displacements. With the equivalent stress point of the cantilever beam during the pull-in process, the pull-in displacement and the pull-in voltage were obtained. The relative errors of the pull-in displacement and the pull-in voltage were compared for the two models. The results showed that the error of the lumped static model was 20.5%, and the error of the pivotal static model was only 5.3%. This showed that the characteristics of the pivotal static model were better than that of the lumped static model.