Sensitivity Calibration of Triaxial High-g Accelerometer Based on the Transverse Effect of Hopkinson Bar

Abstract

This article proposes a sensitivity calibration method for triaxial accelerometers, aiming to eliminate calibration errors caused by the transverse effects of the calibration device on the accelerometers. First, we establish a matrix model that relates the triaxial acceleration excitation loads to the sensor voltage sensitivity. Next, we introduce an orthogonal calibration method based on the Hopkinson bar. Using three laser Doppler velocimeters (LDVs), we simultaneously measure the 3-D orthogonal excitation acceleration at the end of the calibration device. We then calculate the impact of the transverse coupling effect between the elastic rod and the anvil on the accelerometer calibration. Finally, we perform calibration experiments on triaxial high-g accelerometers using the proposed and conventional methods. The sensitivity matrices for each method were computed using the least squares method. We evaluate the calibration accuracy using relative error and root mean square error (RMSE) metrics. The results demonstrate that the proposed orthogonal calibration method reduces the average relative error by 60.3% and the RMSE by 64.3% compared with the conventional calibration method. The proposed orthogonal calibration method achieves higher precision and better reflects the sensitivity characteristics of triaxial accelerometers.