Impact damage detection on composites using optical NDT techniques

The sensitivity of the electromechanical impedance to structural damage under varying temperature is investigated in this paper. An approach based on maximizing cross-correlation coefficients is used to compensate temperature effects. The experiments are carried out on an air plane conform carbon fiber reinforced plastic (CFRP) panel (500mm x 500mm x 5mm) instrumented with 26 piezoelectric transducers of two different sizes. In a first step, the panel is stepwise subjected to temperatures between-50 °C and 100 °C. The influence of varying temperatures on the measured impedances and the capability of the temperature compensation approach are analyzed. Next, the sensitivity to a 200 J impact damage is analyzed and it is set in relation to the influence of a temperature change. It becomes apparent the impact of the transducer size and location on the quality of the damage detection. The results further indicate a significant influence of temperature on the measured spectra. However, applying the temperature compensation algorithm can reduce the temperature effect at the same time increasing the transducer sensitivity within its measuring area. The paper concludes with a discussion about the trade-off between the sensing area, where damage should be detected, and the temperature range, in which damage within this area can reliably be detected.

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Impact Damage Detection of FRP Laminates Based on Spectrum Analysis of Lamb Waves

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A ◽

10.1299/kikaia.78.879 ◽

2012 ◽

Vol 78 (790) ◽

pp. 879-889

Author(s):

Akihiro WADA ◽

Shinya MOTOGI ◽

Tomohiro YAMASAKI

Keyword(s):

Damage Detection ◽

Spectrum Analysis ◽

Lamb Waves ◽

Impact Damage

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Feasibility of PZT ceramics for impact damage detection in composite structures

10.1063/1.4914716 ◽

2015 ◽

Cited By ~ 3

Author(s):

Gerges Dib ◽

Ermias Koricho ◽

Oleksii Karpenko ◽

Mahmood Haq ◽

Lalita Udpa ◽

...

Keyword(s):

Damage Detection ◽

Composite Structures ◽

Impact Damage ◽

Pzt Ceramics

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A transmittance-based methodology for damage detection under uncertainty: An application to a set of composite beams with manufacturing variability subject to impact damage and varying operating conditions

Structural Health Monitoring ◽

10.1177/1475921718779190 ◽

2018 ◽

Vol 18 (1) ◽

pp. 318-333 ◽

Cited By ~ 5

Author(s):

Aggelos G Poulimenos ◽

John S Sakellariou

Keyword(s):

Damage Detection ◽

Production Line ◽

Composite Structures ◽

Impact Damage ◽

Parametric Representation ◽

Composite Beams ◽

Operating Conditions ◽

Ratio Test ◽

Detection Characteristic ◽

Testing Procedures

Oftentimes, the complexity in manufacturing composite materials leads to corresponding structures which although they may have the same design specifications they are not identical. Thus, composite parts manufactured in the same production line present differences in their dynamics which combined with additional uncertainties due to different operating conditions may lead to the complete concealment of effects caused by small, incipient, damages making their detection highly challenging. This damage detection problem in nominally identical composite structures is pursued in this study through a novel data-based response-only methodology that is founded on the autoregressive with exogenous (ARX) excitation parametric representation of the transmittance function between vibration measurements at two different locations on the structure. This is a statistical time series methodology within which two schemes are formulated. In the first, a single-reference transmittance model representing the healthy structure is employed, while multiple transmittance models from a sample of available healthy structures are used in the second. The model residual signal constitutes for both schemes the damage detection characteristic quantity that is used in appropriate hypothesis testing procedures with the likelihood ratio test. The methodology is experimentally assessed via damage detection for a population of composite beams which are manufactured in the same production line representing the half of the tail of a twin-boom unmanned aerial vehicle. The damage detection results demonstrate the superiority of the multiple transmittance models based scheme that may effectively detect damages under significant manufacturing variability and varying boundary conditions.

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