Damage Detection and Characterization in Composites Using a Geometric Modification of the RAPID Algorithm

Abstract

Structural Health Monitoring (SHM) of aircraft structures, which are manufactured more and more using composite material, is a well-established technique for increasing reliability and reducing maintenance costs. Implementing damage inspection algorithms that run in dedicated electronic systems helps reduce big data processing time with improved results. RAPID (Reconstruction Algorithm for Probabilistic Inspection of Damage) algorithm, developed some years ago, provides a technique to identify and characterize damages both in metallic and composite materials. However, this algorithm sometimes provides inaccurate predictions of the damage location, caused mainly by the influence of path intersection points among transducers, that can mask the current location of damages. This work presents a geometrical modification of standard RAPID algorithm (RAPID-G) that mitigates the influence of the intersection point between sensor paths. The results highlight that the location of damages improves significantly with this modification of the algorithm. Index Terms-Structural health monitoring, composite, RAPID, Lamb waves, guided waves, damage detection, damage characterization. I. INTRODUCTIONS TRUCTURAL Health Monitoring (SHM) systems integrate current non-destructive testing (NDT) techniques in structures, facilitating their status analysis and monitoring [1]. This implementation reduces maintenance costs and increases aeronautical structures' safety and reliability. This technology aims to achieve the highest level of automation for monitoring and providing data from structures in real-time. Lamb waves ultrasound testing [2] is one of the most widely used techniques for damage detection in aircraft structures. These waves (mechanical elastic) propagate through small thick material,

Structural health monitoring of an adhesively bonded CFRP aircraft fuselage by ultrasonic Lamb Waves

“…However, because of the property of the elliptical method, that a greater intensity is given to the intersection points of the paths, the maximum always occurs at the intersection of the two paths in this situation, where sensor 1 is located. To avoid this disadvantage caused by the model, it needs to be further developed, a simple improvement could be use of a shape function, like the one introduced by Azuara et al., 24 that decreases the weight on the intersection points.…”

“…Several approaches in that direction has been taken by Hua and Azuara. 24,26 Detailed finite element models are considered to optimize the array of sensors and the signal processing methodology ideally, which are the steps to accurately identify failures in the adhesive.…”

Influence and Compensation of Temperature Effects for Damage Detection and Localization in Aerospace Composites

“…Due to the chosen distribution of the sensors over the sample, as well as its anisotropy, the RAPID [28] algorithm was chosen for the detection and location of the damage. However, the preliminary results were not as expected, hence, to avoid the influence of the intersection points in the image results, the modification of the algorithm called RAPID-G [29] was used, and finally the effectiveness of each method was assessed.…”

“…In this paper, the SHM traditional point of view was applied, using baseline datasets information, and a data-driven method was used for the evaluation and correction of temperature effects [26], assuming that the temperatures distribution field on the sample was homogeneous [27], as well as based on minimizing the difference between several types of baseline tests, adjusting each of them to a reference temperature and, with the use of polynomial regression, being able to estimate the parameters used for compensating a signal recorded at the current damaged state, at a certain temperature at which the baseline data is not available. Finally, to check the effectiveness of the method applied to damage detection and location, the data from the current state were adapted to several available baselines at several different temperatures, and an artificial damage was detected and located, using an imaging algorithm (RAPID, Reconstruction Algorithm for Probabilistic Inspection of Damage) [28] and, based on previous experience [29], a modification of this algorithm (RAPID-G). The effectiveness of the combination of these two methodologies (both signal reconstruction and imaging) is analyzed in this paper, providing a solution to achieve better damage detection and localization in plate-like structures.…”

Structural Health Monitoring Using Ultrasonic Guided-Waves and the Degree of Health Index

“…In this sense, a number of methods have been proposed in the literature. One such example is the reconstruction algorithm for probabilistic inspection of defects (RAPID) [ 27 ] and further variations of the same [ 28 ]. This method is able to localize defects by using signal difference coefficients of sensor pairs.…”