Passenger and cargo volumes are growing globally. This means increased requirements for efficient monitoring systems, which must provid the highest possible level of safety. Fraunhofer IKTS develops such systems and services for the condition monitoring of components. They allow for recognizing damages in real time and repair it at an early stage to avoid serious consequential damage.
Methods and measuring systems for condition monitoring are used more and more often for rail vehicle components. Robust and autonomous solutions are needed for freight traffic in particular. Fraunhofer IKTS supplies systems for the monitoring of wheels and wheel bearings with the ability to detect blocked brakes, defective springs and excessive inclinations (e.g. due to incorrect loading).
The institute offers a measuring system for the monitoring of wheels of high-speed (ICE) trains integrated into the hollow shaft. Its working principle is based on high-frequency structure-borne noise generated by the contact between wheel and rail, while also making use of acceleration and temperature data. By adapting the signal processing algorithm, it becomes possible to monitor the railway tracks as well. The sensor nodes consist of modules for the sensors as well as signal processing and radio processes.
With lower fuel consumption for passenger planes in mind, more and more OEMs use lightweight materials to reduce aircraft weight. However, the carbon fiber composite materials (CFRP) used for this often pose significant challenges with regard to processing, quality control and inspections.
Fraunhofer IKTS offers customized solutions for the system integration of sensors for condition monitoring, support of static and dynamic material fatigue tests, simulations of the propagation of elastomechanical waves in various materials, 3D laser vibrometry for the visualization of structural damage as well as statistical analyses for defect diagnosis and comprehensive signal processing techniques.
Acoustic emission testing allows to quickly and safely deter- mine which areas emit elastic waves due to external stress, e.g. from growing cracks. The location of the damage can be determined by the signals’ travel time from the individual noise source to a number of sensors. This is followed by further analyses with conventional non-destructive test methods, or rather by tests with controlled parameters.
Specifically for lightweight structures in the automotive sector, IKTS has developed a monitoring system that can be integrated in complex components. This allows to monitor the fiber composite material more reliably than it is possible with conventional monitoring and inspection methods. Sensors and electronics are embedded in the manufacturing stage without affecting the structure. Near-surface integration ensures optimal coupling between sensor and test object.