Fraunhofer Institute for High Frequency Physics and Radar Techniques FHRThe FiberRadar project, part of the NRW Lead Market initiative, is developing a method for the automated and non-destructive analysis of fiber-reinforced composites. The goal is the early detection of defects in glass-fiber-reinforced plastics, such as those used in the rotor blades of wind turbines. In the manufacture of fiber-reinforced composite components, multiple layers of glass fiber mats are stacked on top of one another, vacuum-sealed, and bonded with resin. Defects in the alignment or orientation of the fibers can significantly impair the mechanical properties of the components. Existing testing methods usually allow only a manual inspection of the top layer, while defects in deeper layers are often not detected until after production. This leads to time-consuming rework or the scrapping of components.
FiberRadar enables non-destructive testing of fiber-reinforced composites
In the NRW flagship project FiberRadar, a method is being developed for automated, precise, and non-destructive analysis of fiber-reinforced materials. The aim is the early, reliable detection of defects in glass fiber-reinforced plastics, such as those used in rotor blades of wind turbines.
During the manufacturing of fiber-reinforced components, several glass fiber mats are layered, vacuum-bonded, and fixed with resin. Defects in the alignment or in the fiber routes can significantly affect the mechanical properties of the parts. Current inspection methods usually allow only manual inspection of the top layer, while defects in deeper layers are often detected only after production. This leads to costly rework or rejection of components.
Enhanced 3D imaging for material inspection
In the FiberRadar project, a fully polarimetric radar system is used that transmits and receives signals in two polarizations. From the resulting four signal combinations, information about the orientation of the fiber plies and possible defects can be derived. Additional refraction compensation improves image quality, enabling reliable analysis of deeper layers as well. This enables a three-dimensional and non-destructive examination of the entire material volume.
For practical use, the radar system is integrated on a robot-assisted platform. The robot scans components automatically during manufacturing and enables continuous quality control. In tests under real conditions, typical defects such as angular errors, undulations, or interrupted fiber layers could be reliably detected—even in concealed layers.
In the FiberRadar project, a technology for precise and scalable monitoring of manufacturing processes for fiber-reinforced materials is being realized, which can be used particularly for wind energy applications, lightweight construction, and for other industrial manufacturing processes.
Project partners and funding
FiberRadar brings together the integrated radar technology from Ruhr University Bochum, the algorithm expertise of Fraunhofer FHR, and the robotics competence of FH Aachen to realize a measurement system that raises quality assurance and process monitoring of fiber-reinforced materials to a new level. Thanks to the involvement of the industrial partner Aeroconcept GmbH, the technology can be directly applied to the manufacturing and monitoring process in rotor blade production and established as a key technology for qualitatively high-grade composites in North Rhine-Westphalia.
The project is enabled by funding under the NRW “New Materials” flagship competition, providing research funds from the European Union to support regionally anchored future technologies, the European Regional Development Fund (ERDF).
