Next Article in Journal
Subsurface Temperature Estimation from Sea Surface Data Using Neural Network Models in the Western Pacific Ocean
Next Article in Special Issue
Machine Learning-Based Detection Technique for NDT in Industrial Manufacturing
Previous Article in Journal
Time-Varying Comovement of Foreign Exchange Markets: A GLS-Based Time-Varying Model Approach
Article

Early Detection of Defects through the Identification of Distortion Characteristics in Ultrasonic Responses

Dipartimento di Ingegneria, Università di Perugia, 06125 Perugia, Italy
*
Author to whom correspondence should be addressed.
Academic Editor: Mario Versaci
Mathematics 2021, 9(8), 850; https://doi.org/10.3390/math9080850
Received: 8 March 2021 / Revised: 8 April 2021 / Accepted: 12 April 2021 / Published: 13 April 2021
Ultrasonic techniques are widely used for the detection of defects in solid structures. They are mainly based on estimating the impulse response of the system and most often refer to linear models. High-stress conditions of the structures may reveal non-linear aspects of their behavior caused by even small defects due to ageing or previous severe loading: consequently, models suitable to identify the existence of a non-linear input-output characteristic of the system allow to improve the sensitivity of the detection procedure, making it possible to observe the onset of fatigue-induced cracks and/or defects by highlighting the early stages of their formation. This paper starts from an analysis of the characteristics of a damage index that has proved effective for the early detection of defects based on their non-linear behavior: it is based on the Hammerstein model of the non-linear physical system. The availability of this mathematical model makes it possible to derive from it a number of different global parameters, all of which are suitable for highlighting the onset of defects in the structure under examination, but whose characteristics can be very different from each other. In this work, an original damage index based on the same Hammerstein model is proposed. We report the results of several experiments showing that our proposed damage index has a much higher sensitivity even for small defects. Moreover, extensive tests conducted in the presence of different levels of additive noise show that the new proposed estimator adds to this sensitivity feature a better estimation stability in the presence of additive noise. View Full-Text
Keywords: non-destructive evaluation; pulse compression; non-linear systems; Hammerstein model non-destructive evaluation; pulse compression; non-linear systems; Hammerstein model
Show Figures

Figure 1

MDPI and ACS Style

Burrascano, P.; Ciuffetti, M. Early Detection of Defects through the Identification of Distortion Characteristics in Ultrasonic Responses. Mathematics 2021, 9, 850. https://doi.org/10.3390/math9080850

AMA Style

Burrascano P, Ciuffetti M. Early Detection of Defects through the Identification of Distortion Characteristics in Ultrasonic Responses. Mathematics. 2021; 9(8):850. https://doi.org/10.3390/math9080850

Chicago/Turabian Style

Burrascano, Pietro, and Matteo Ciuffetti. 2021. "Early Detection of Defects through the Identification of Distortion Characteristics in Ultrasonic Responses" Mathematics 9, no. 8: 850. https://doi.org/10.3390/math9080850

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop