Analytical modeling of piezoelectric 6-degree-of-freedom accelerometer about cross-coupling degree

Abstract

In order to realize the optimize design of the 6-degree-of-freedom (6-DF) accelerometer according to its cross-coupling degree, the analysis mathematical modeling of the accelerometer′s cross-coupling must be carried out. In this work, the working principle and structure characteristics of the six-wafer piezoelectric 6-DF-accelerometer are analyzed. According to the mechanical analysis of the sensing element, the 6-DF component force equation of the accelerometer and the composite formula of the six-wafer are deduced. Analytical mathematical model and cross-coupling graph model of cross-coupling degree are derived by analyzing the static structure and coupling mechanism. The numerical simulation experiment is carried out using ANSYS software. An experimental prototype of the 6-DF-accelerometer is fabricated. The vibrator is used as a loading source for calibration. The experimental results show that the Pearson correlation index of the multiple parameter model about the cross-coupling degree, the numerical simulation model, and calibration experiment is 0.9881. The results of the cross-coupling research of the three models are consistent, which verifies the effectiveness of the analytical mathematical model. Coupling direction and coupling number were obtained based on the cross-coupling graph model. The results of this work provide the theoretical basis for further research on the active optimization design method of 6-DF-accelerometer based on cross-coupling.