Research on micro-leverage in monolithic quartz resonant accelerometer

In this study, the application of micro-leverage in the monolithically all-quartz resonant accelerometer is proposed. The magnification of the micro-leverage structure used for a large size double-ended tuning fork (DETF) was analyzed. The effect of DETF's dimension both on its own force-frequency sensitivity and micro-leverage's magnification was investigated. Through the study of the relationship between DETF's force-frequency sensitivity and micro-leverage's magnification, the effect of micro-leverage and the DETF system on the sensitivity of the accelerometer was obtained. The problem of big error in theoretical calculation of micro-leverage magnification was solved because the structural arrangement of the output beam was ignored in the derivation process. The correctness of the analysis was verified by theoretical calculation, simulation, and the experiment. The equivalent structures of tension (compression) stiffness and flexural stiffness of the micro-leverage output beam were obtained by analyzing and simplifying the composite structure of the link beam and DETF. By simplifying the mechanical model of micro-leverage, the amplification factor K of micro-leverage is deduced to be 23. Therefore, the theoretical sensitivity of the sensor is 15.6 Hz/g. The experimental results show that the sensitivity of the accelerometer with the micro-leverage is 16.1 Hz/g, which is close to the theoretical analysis results.