Conventional methods for the structural nondestructive testing (NDT) such as pulsed eddy current (PEC), ultrasonic detection (UT), and so on are based on the output signal interpretation technique of the NDT system to extract the features to assess the structural health. In this article, a novel NDT method for the structural health monitoring from the different perspective is proposed, which is based on the structural system model between the exciting input and output response. Nonlinear autoregressive moving average with exogenous inputs (NARMAX) is used to establish the time domain model between the input signal and the output response. Frequency response (FRF) of NARMAX model from the time domain data is proposed to obtain the indicators to assess the structural health. The effectiveness and advantage of the proposed method are tested with two sets of experimental data by comparison with the existing method.

中文翻译：

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基于模型的非线性超声系统识别方法用于机械结构健康评估

用于结构无损检测（NDT）的常规方法（例如脉冲涡流（PEC），超声检测（UT）等）基于NDT系统的输出信号解释技术来提取特征以评估结构健康。本文提出了一种新颖的无损检测方法，该方法基于激励输入和输出响应之间的结构系统模型，从不同角度对结构进行健康监测。具有外部输入的非线性自回归移动平均值（NARMAX）用于建立输入信号与输出响应之间的时域模型。提出了基于时域数据的NARMAX模型的频率响应（FRF），以获得评估结构健康的指标。