Guided ultrasonic waves for impact damage detection in composite panels

This paper investigates the propagation of guided ultrasonic waves and the interaction with impact damage in composite plates using a full three-dimensional Finite Element analysis. Impact damage in the composite plate was modeled as rectangular- and T-shaped delaminations. In order to provide guidelines for extending the modeling of realistic multimode impact damage, the impact damage was modeled as a combination of the delamination and reduced materials properties. The information obtained from these methods was compared to the experimental results around the damage area for a validation. There was a reasonable similarity between the experimental and FE results. The FE simulations can effectively model the scattering characteristics of the A0 mode wave propagation in anisotropic composite plates. This suggests that the simplified and easy-to-implement FE model could be used to represent the complex impact damage in composite plates. This could be useful for the improvement of the FE modeling and performance of guided wave methods for the in-situ NDE of large composite structures.

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Ultrasonic/Guided Waves for Structural Health Monitoring

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.293-294.49 ◽

2005 ◽

Vol 293-294 ◽

pp. 49-62 ◽

Cited By ~ 11

Author(s):

W.J. Staszewski

Keyword(s):

Damage Detection ◽

Structural Damage ◽

Guided Waves ◽

Ultrasonic Waves ◽

Detection Methods ◽

Smart Sensor ◽

Large Structures ◽

Guided Ultrasonic Waves ◽

Damage Monitoring ◽

Recent Developments

Structural damage detection and monitoring is one of the major maintenance activities in transportation, processing and civil engineering. Current procedures are based on scheduled inspections which are often time/labour consuming and expensive. Guided ultrasonic waves offer the ability of inspecting large structures with a small number of transducers. Recent developments in smart sensor technologies allow for integration of these transducers with monitored structures. This is associated with a new design philosophy leading to more efficient and economically attractive structures. The paper briefly discusses various damage detection methods based on structural, ultrasonic and guided ultrasonic waves. The focus is on recent research advances in damage monitoring techniques, smart sensor technologies and signal processing.

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Remote inspection system for impact damage in large composite structure

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2014.0631 ◽

2015 ◽

Vol 471 (2173) ◽

pp. 20140631 ◽

Cited By ~ 16

Author(s):

C. H. Zhong ◽

A. J. Croxford ◽

P. D. Wilcox

Keyword(s):

Damage Detection ◽

Impact Damage ◽

Electromagnetic Coupling ◽

Random Noise ◽

Inspection System ◽

High Signal ◽

Single Shot ◽

Composite Panels ◽

Large Area ◽

Baseline Subtraction

A significant opportunity for reducing the weight of composite aircraft is through the development of an economically efficient method to detect barely visible or invisible impact damage sustained in service. In this paper, a structurally integrated, inert, wireless system for rapid, large-area impact damage detection in composite is demonstrated. Large-area inspection from single sensors using ultrasonic-guided waves is achieved with a baseline-subtraction technique. The wireless interface uses electromagnetic coupling between coils in the embedded sensor and inspection wand. Compact encapsulated sensor units are built and successfully embedded into composite panels at manufacture. Chirp-based excitation is used to enable single-shot measurements with high signal-to-random-noise ratio to be obtained. Signal processing to compensate for variability in inspection wand alignment is developed and shown to be necessary to obtain adequate baseline subtraction performance for damage detection. Results from sensors embedded in both glass fibre and carbon fibre-reinforced composite panels are presented. Successful detection of a 10 J impact damage in the former is demonstrated at a range of 125 mm. Quantitative extrapolation of this result suggests that the same level of impact damage would be detectable at a range of up to 1000 mm with an inspection wand alignment tolerance of 4 mm.

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