An indirect comparison quasi-static calibration method for piezoelectric pressure sensors based on an inverse model

Abstract

This graph represents the design schematic of an inverse model, which is used to predict the reference pressure curves and reference peak pressures. The inverse model is established using a linear second-order difference equation. It is supposed that p represents the input pressure curve of the calibrated sensor and y represents the voltage response curve of the calibrated sensor. The input pressure curve of the calibrated sensor is the average response curve of the reference pressure sensors. Where y (1) represents the 1-derivative of y , and y (2) represents the 2-derivative of y . • An novel indirect comparison quasi-static calibration method for piezoelectric pressure sensors was proposed. • An inverse model was established to predict reference pressures. • Reference pressure sensors were used only once during the acquisition of modeling data of the inverse model. • The calibration accuracy of the proposed method was compared with the direct comparison quasi-static method. Quasi-static calibration is an effective method to ensure the measurement accuracy of piezoelectric pressure sensors. In this paper, a novel indirect comparison quasi-static calibration method is proposed. An inverse model is established by a linear second-order differential equation and used to predict reference pressure curves and reference peak pressures. The working principle of the drop-weight device and calibration steps are described. Calibration tests show that the inverse model has good prediction accuracy. Compared with the peak pressures measured by the reference pressure sensors, the maximum prediction error of the peak pressures calculated by the inverse model is 0.29%. Reference pressure sensors are used only once during the acquisition of modeling data of the inverse model, which can effectively extend the service life of the reference pressure sensors. Furthermore, the proposed method has good calibration accuracy as well as the direct comparison method.