Electromechanical impedance (EMI)-based techniques have been widely used as a potential nondestructive evaluation (NDT) technique in the field of structural health monitoring (SHM), especially for the civil, mechanical, and aerospace engineering. However, one of the greatest challenges for this kind of technique is its impedance measurement hardware, which is usually expensive, bulky, and heavy, such as the professional impedance analyzer (WK6500B, Wayne Kerr), and thus seriously limited its practical application. In this paper, a small, lightweight and low power consumption SHM system combining with the low-cost miniature impedance board AD5933 was experimentally studied and investigated to validate its actual performance in the impedance measurement and structural damage identification. At first, the calibration and measurement procedure of AD5933 was detailly introduced by a simple impedance test for a free PZT patch, and its impedance calibration performance was also validated by comparing the signatures with ones measured by WK6500B. Then, in order to further validate its feasibility and effectiveness of the AD5933 in practical applications, a threaded pipe connection specimen was assembled in laboratory and then connected with AD5933 to acquire its impedance signatures under different loosening severities. The final results demonstrate that that measured impedance by the AD5933 presented a good consistence with the measurement by the WK6500B, and the evaluation board was successfully utilized for the loosening severities identification and quantitatively evaluation.

中文翻译：

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用于螺纹管接头松动监测的微型阻抗板的实验评价

基于机电阻抗 (EMI) 的技术已被广泛用作结构健康监测 (SHM) 领域的潜在无损评估 (NDT) 技术，尤其适用于土木、机械和航空航天工程。然而，这种技术的最大挑战之一是其阻抗测量硬件，通常昂贵、笨重、笨重，如专业阻抗分析仪（WK6500B，Wayne Kerr），严重限制了其实际应用。本文结合低成本微型阻抗板AD5933，对一种体积小、重量轻、功耗低的SHM系统进行了实验研究和研究，以验证其在阻抗测量和结构损伤识别方面的实际性能。首先，通过对自由PZT贴片的简单阻抗测试详细介绍了AD5933的校准和测量过程，并通过与WK6500B测量的签名进行比较来验证其阻抗校准性能。然后，为了进一步验证 AD5933 在实际应用中的可行性和有效性，在实验室组装螺纹管连接样品，然后与 AD5933 连接以获得其在不同松动严重程度下的阻抗特征。最终结果表明，AD5933测得的阻抗与WK6500B测得的阻抗具有良好的一致性，评估板成功用于松动严重程度的识别和定量评估。