Guided elastic waves in the frequency range of a few hundred kHz, generated and detected by appropriate transducer arrays, are used to monitor the structural integrity of pipes by comparing their actual state with a predefined reference state. For these purposes, theoretical, numerical, and experimental results are combined to study guided wave propagation… (More)
Traditional vibration-based monitoring techniques provide general information about the investigated structure by identifying and analyzing specific resonance modes. Using low frequencies, they are limited to the identification of large defects, and in the precision of their localisation as well. The paper shows that vibration monitoring of essential… (More)
The condition of avionic structures has to be continuously monitored. In favor of such a Structural Health Monitoring (SHM), the evaluation of acoustic Lamb waves can contribute substantially. Methods for an effective, signal processing are required to detect wave modes and to reduce noise as much as possible. Frequently, a further necessity exists to… (More)
The market increasingly demands remote monitoring sensors and electronics for safety-related industrial equipment, transport vehicles and also building structures. In these applications the robustness of the electronics and the reliability of the packaging technology are key factors. Reliability requirements are for electronic modules are derived from… (More)
New materials and lightweight structures call for new concepts of reliability assurance and maintenance. The progress in microelectronics and micro-electromechanical systems (MEMS) allows development of highly integrated smart systems in large quantities at low costs that combine signal generation, data pre-processing and wireless communication accompanied… (More)
The paper describes a structural health monitoring concept based on the evaluation of acoustic Lamb waves. Using a suitable damage indicator like the correlation coefficient it is possible to detect and localize defects in the observed structure. The functional capability was shown in statical test of a part of a rotor blade.
In the framework of the EU project SAFE PIPES (Safety Assessment and Lifetime Management of Industrial Piping Systems) elastic waves in the frequency range between 70 and 350 kHz, generated and detected by appropriate transducer arrays , are used to monitor the structural integrity of pipes by comparing their actual state with a predefined reference state.… (More)