Development of an AD5933-based impedance calibration and measurement technology using piezoceramic transducers

Abstract

AD5933 evaluation board is expected to promote the practicability of electromechanical impedance (EMI) based structural damage identification technology. For the evaluation board, the calibration before use is essential and important. In this study, a novel self-calibration method is proposed to help the board to improve its independence, measurement accuracy, and data continuity for the impedance measurement by selecting the optimal feedback resistance based on data deviation characteristics of the AD5933 board. In this research, to clearly present the principle of the proposed method, a pretest of impedance measurement via AD5933 board was conducted at first. Then, its impedance measurement performance was further investigated by a series of measurements tests, and the results demonstrated that the proposed method provide the board the ability to obtain the impedance measurement with higher accuracy and better data continuity comparing with the conventional subrange calibration method. At last, its feasibility and effectiveness for structural damage identification has also been validated by a bolt loosening identification test on a steel plate.