Guided waves for online monitoring of composites
16 Feb 2017-Vol. 1806, Iss: 1, pp 030013
TL;DR: In this article, the authors explored the use of embedded waveguides for monitoring delamination type defects in composites, which confine the wave transmission in one dimension and waves leak only through the opening provided, which enhances the capability to inspect large composite structures with very low attenuation rate.
Abstract: Aerospace & Automotive industries make extensive use of composite structures, often with complex geometries. Ultrasonic guided waves are attractive for long-range inspection of large-scale structures. However surface based transducers that are typically used, lead to two-dimensional wave propagation, limiting the applicability of guided wave methods. This work explores the use of embedded waveguides for monitoring delamination type defects in composites. These waveguides confine the wave transmission in one dimension and waves leak only through the opening provided, which enhances the capability to inspect large composite structures with very low attenuation rate. Inaccessible areas can be inspected and inter-laminar delamination detection can be achieved. Live monitoring and assessment of discontinuities can be accomplished effectively by using this mechanism.
Citations
More filters
01 Oct 2018
Abstract: Ultrasonic guided waves based non-destructive testing (NDT) is attractive due to its potential for long range inspection. In NDT, fiber Bragg gratings (FBG) sensor is widely adopted due to its rugged wavelength encoded information and immunity to electromagnetic interference (EMI). In this paper we discuss the reception of ultrasonic guided waves in a glass fiber reinforced plastic (GFRP) composite plate using a surface bonded FBG sensor. Experimentally deduced values for wave velocity and attenuation are compared with the theoretical values.
2 citations
Cites background from "Guided waves for online monitoring ..."
...Structural health monitoring of composites has been demonstrated through several techniques for monitoring features such delamination, stiffness of composite plates and other mechanical properties [2], [3], [4], [5], [6]....
[...]
...Interrogation with ultrasonic guided waves are attractive as it provides opportunity for defect identification [6] and localization [7]....
[...]
01 Jan 2018
TL;DR: In this paper, the authors presented an online monitoring system to measure the chamfer quality of replica boss hole post deburring process, and the features that correlate to the deburring stages (passes) were extracted.
Abstract: The monitoring of surface finishing processes in aerospace manufacturing industry becomes one of key issues to maintain the overall quality of product or part. To date, the surface quality monitoring post machining processes such as deburring, use visual inspection, surface roughness test or laser gap gun. The whole manufacturing process then requires a considerable amount of time as the production line must be halted due to these measurements taking place. This study presents an online monitoring system to measure the chamfer quality of replica boss hole post-deburring process. Vibration signal was measured during the deburring process and the features that correlate to the deburring stages (passes) were extracted. This paper focuses on the validation of actual vibration signal with the modal analysis of work coupon (replica boss hole) to obtain the correlation between the vibration amplitude level on particular region and the mode shape of work coupon during the deburring process.
2 citations
References
More filters
TL;DR: A comprehensive review on the state of the art of Lamb wave-based damage identification approaches for composite structures, addressing the advances and achievements in these techniques in the past decades, is provided in this paper.
1,350 citations
TL;DR: In this article, an ultrasonic guided wave structural health monitoring (SHM) system was developed for aircraft wing inspection, where small, low-cost and light-weight piezoelectric (PZT) discs were bonded to various parts of the aircraft wing, in a form of relatively sparse arrays, for simulated cracks and corrosion monitoring.
Abstract: This work focuses on an ultrasonic guided wave structural health monitoring (SHM) system development for aircraft wing inspection. In part I of the study, a detailed description of a real aluminum wing specimen and some preliminary wave propagation tests on the wing panel are presented. Unfortunately, strong attenuation and scattering impede guided waves for large-area inspection. Nevertheless, small, low-cost and light-weight piezoelectric (PZT) discs were bonded to various parts of the aircraft wing, in a form of relatively sparse arrays, for simulated cracks and corrosion monitoring. The PZT discs take turns generating and receiving ultrasonic guided waves. Pair-wise through-transmission waveforms collected at normal conditions served as baselines, and subsequent signals collected at defected conditions such as rivet cracks or corrosion detected the presence of a defect and its location with a novel correlation analysis based technique called RAPID (reconstruction algorithm for probabilistic inspection of defects). The effectiveness of the algorithm was tested with several case studies in a laboratory environment. It showed good performance for defect detection, size estimation and localization in complex aircraft wing structures.
670 citations
TL;DR: In this paper, the authors provide a state-of-the-art review of guided wave based structural health monitoring (SHM) and highlight the future directions and open areas of research in guided wave-based SHM.
Abstract: The paper provides a state of the art review of guided wave based structural health monitoring (SHM). First, the fundamental concepts of guided wave propagation and its implementation for SHM is explained. Following sections present the different modeling schemes adopted, developments in the area of transducers for generation, and sensing of wave, signal processing and imaging technique, statistical and machine learning schemes for feature extraction. Next, a section is presented on the recent advancements in nonlinear guided wave for SHM. This is followed by section on Rayleigh and SH waves. Next is a section on real-life implementation of guided wave for industrial problems. The paper, though briefly talks about the early development for completeness,. is primarily focussed on the recent progress made in the last decade. The paper ends by discussing and highlighting the future directions and open areas of research in guided wave based SHM.
664 citations
01 Jan 1997
TL;DR: In this article, a general-purpose program that can create dispersion curves for a very wide range of systems and then effectively communicate the information contained within those curves is presented, using the global matrix method to handle multi-layered Cartesian and cylindrical systems.
Abstract: The application of guided waves in NDT can be hampered by the lack of readily available dispersion curves for complex structures. To overcome this hindrance, we have developed a general purpose program that can create dispersion curves for a very wide range of systems and then effectively communicate the information contained within those curves. The program uses the global matrix method to handle multi-layered Cartesian and cylindrical systems. The solution routines cover both leaky and non-leaky cases and remain robust for systems which are known to be difficult, such as large frequency-thicknesses and thin layers embedded in much thicker layers. Elastic and visco-elastic isotropic materials are fully supported; anisotropic materials are also covered, but are currently limited to the elastic, non-leaky, Cartesian case.
485 citations
TL;DR: In this paper, the authors proposed a method for online detection of initial damage in composite structures based on energy variation of structural dynamic responses decomposed using wavelet analysis, which can detect extremely small cracks in composite plates.
130 citations