Accelerometer identification by high shock intensities using laser interferometry

摘要

A signal processing method for identifying the input/output behavior of accelerometers is proposed. The method includes data preprocessing applied to interferometrically measured displacement signals and to electrical responses of the accelerometer. The identification procedure itself uses a prediction error approach based on a second order transfer function model. The transfer function of the accelerometer parameterized by gain factor, damping constant and resonant frequency is fitted to the input/output signals utilizing a nonlinear optimization procedure. The method was tested by application to calibration measurement of high shock intensities. The model shows a good performance in describing the output data of the accelerometer. The parameter estimates are characterized by small measurement uncertainties. Hence, the method can be recommended for application in the calibration of accelerometers with high shock intensities. Furthermore, the dynamic model identified describes the accelerometer's input/output behavior for both stationary and transient accelerations allowing accurate measurements of mechanical vibrations and shocks.