Design of a Square MEMS Piezoelectric Accelerometer With a Wide Range of Applicability, a Low Transverse Sensitivity Ratio, and High Accuracy

摘要

In this study, we attempt to design a new square MEMS lead-free piezoelectric accelerometer that can be used simultaneously in a wider frequency range than has been available in the past and in low-G sensing environments with high accuracy and low transverse sensitivity. Low transverse sensitivity is an important factor for high-accuracy accelerometers. The device is designed through the use of a structural formula, and ANSYS software is used to simulate the vibration mode and resonance frequency of the device, after which the MEMS process is used to complete the fabrication of the devices. The performance of the proposed device indicated that the resonance frequency was 1740 Hz, with a simulation error of only 3.3%; the Z-axis sensitivity was 1.96 mV/g, and the transverse sensitivity ratio was 0.6%. To the best of the author’s knowledge, the transverse sensitivity obtained in the present work is the lowest compared to the published data and specifications for commercial devices. It was successfully applied to a low-frequency robotic arm and a high-frequency turbo pump, where the operational status of the devices was monitored in-situ with high accuracy.