高g值加速度环境微结构动态特性

Dynamic Characteristic of Microstructure in High g Acceleration Environment

为研究微机电系统(Microelectro-mechanical systems,MEMS)中微结构在高g值加速度环境中的动态特性,研究高g值加速度环境微结构动态测试技术,建立高g值环境微结构动态测试装置,研制适用于高g值加速度环境的压电陶瓷底座激励装置,制备集成压阻元件的典型梁—质量块微结构,测试典型MEMS微结构在从常态到10000g加速度环境中动态特性及其变化规律。测试结果显示,在高g值加速度作用下,当微结构发生大变形处于非线性状态时,微结构谐振频率随加速度的增大而提高;而当微结构处于线性小变形状态时,微结构谐振频率不随外部加速度作用发生变化;在大变形及小变形状态下,外部高g值加速度载荷对微结构阻尼比均不产生明显影响。测试结果与采用应力刚化非线性有限元模型分析结果具有很好的一致性。

To study the dynamic characteristics of micro electro-mechanical systems（MEMS） microstructures in high-g acceleration environment,the dynamic testing technology in high-g acceleration environment is systematically studied and the dynamic testing equipment is developed.The base excitation device which uses piezoelectric ceramic as the driving source is established.The typical beam─mass block microstructure which integrates the piezoresistive element is prepared.The dynamic characteristic and its change law of the typical MEMS microstructure in 0g to 10 000g acceleration environment are studied through experiments.The experimental results show that under the action of high-g acceleration,when the microstructure has large deformation,thus being in the nonlinear state,the natural frequency of the microstructure gets higher with the increase of acceleration;when the microstructure only has small deformation and is in linear state,its natural frequency does not change with the action of external acceleration.Whether in large or small deformation state,the external high-g acceleration has no effects on the damping ratios of the microstructure.The experimental result is in good agreement with the analysis result of nonlinear finite element modal with stress stiffening effect.