Frequency Characteristic Measurement of High-G Accelerometers Based on Down-Step Response

Abstract

High-G accelerometers are a critical component for the accurate measurement of high-impact signals. Each high-G accelerometer must be frequency calibrated to ensure the reliability of its measurements. However, the existing methods for measuring the frequency response of high-G accelerometers use sinusoidal shocks for excitation, which is not only complex but also prone to noise interference. To overcome this problem, we propose a down-step response method (DSRM) to measure the frequency characteristics of high-G accelerometers. First, the aluminum foam was selected as the cushion material for the shock test to generate the down-step shock signal. Then, the response signal of the high-G accelerometer under the down-step shock excitation was converted into a step response signal. Finally, the features in the step response signal were extracted to calculate the frequency characteristics of the accelerometer. Experimental results show that DSRM outperforms the conventional fast Fourier transform (FFT) and can significantly reduce noise interference while reducing the equipment requirements. The results demonstrate the proposed measurement method’s high reliability, stability, and convenience.