STW27 nov 2012 13:38
The Aviation research programme is taking initiative to propose a research with the University of Amsterdam, the Delft Technical University, and industry partners Fokker, Technobis and NLR. This 4-year research aims to deliver improved techniques to detect defects in composite structures; Integral Monitoring of Composite Structures with Ultrasonic Verification.
Technologiestichting STW is asked to fund this research. One of the promising techniques is Ultrasonic Verification, which is developed by the University of Amsterdam. This method is similar to the traditional non-destructive test methods that are used to detect sound wave changes in materials. The developed method can inspect large surfaces with a limited number of sensors, and it is possible to apply in flight monitoring. A Dutch patent is administered, and a European patent is requested. The current research proposal aims to find solutions to problems that need to be fixed in order to apply Ultrasonic Verification in aerospace.
- The current method is developed based on piezo-electric transducers. However, the application of Figer Bragg Gratings (FBG) in fiber optics seems more attractive because of the easier implementation in aircraft structures.
- The network of sensors is more robust and simple in comparison to electronic sensor networks. The feasibility of Ultrasonic Verification with the use of FBG needs to be proven, and the optimal parameter settings need to be established.
- The technology is proven with the use of small objects, such as plates and bars. However, the technology also has to be proven on typical aircraft structures made out of composite materials, such as wings, elevators, et cetera.
- In theory, it is shown that the exact location of the defect could be calculated from the measuring signals. This reduces inspection time when inspecting large surfaces. The theory still needs to be tested in practice.