Dynamic characteristics and testing techniques of microstructures under high load

Abstract

To study the dynamic characteristics of micro inertial components under high load, dynamical equation including the effect of dead load (constant acceleration) is discussed based on Hamilton's principle. The effects of acceleration on the natural frequency of a typical micro inertial component, i.e. the beam-proof mass structure, are analyzed with finite element method. The natural frequency of microstructure was calculated with different high g-force accelerations and beam length. The results show the natural frequency of microstructure gets higher as the inertial force increases because the structural stiffness is strengthened by the load-induced stiffness. A dynamic testing experimental instrument was developed, and experiment was carried out with the instrument. The instrument can generate high g-force environment, impose impact on microstructure and measure the corresponding response. The experimental results show that the resonant frequency of microstructure gets higher as the environmental acceleration increases, and that is consistent with theoretical analysis. The study has practical value for design and fabrication of high g-force micro-inertial components.