‘Healthier’ airplanes Safer aircraft require not only more reliable parts and systems but better ways of reducing damage to parts, of identifying when damage has occurred and of localising the damage so it can be fixed. EU researchers have advanced the means with which all this may be done in the near future. Industrial Technologies © Shutterstock Methods for airline maintenance and service life evaluation have evolved tremendously over the last century. Manufacturers have progressed from static safety evaluations (no consideration of movement of parts or systems) to fail-safe (focused on not allowing any failures) to damage tolerant (capable of functioning with slight damage), enabling better ways of predicting possible failure mechanisms and continued function in light of them. Two new approaches that hold promise for reduced maintenance, increased reliability and longer service life are structural health monitoring (SHM) and vibration damping. The former refers to continuous monitoring of components and systems to record changes and warn of impending threats to performance and safety. The latter refers to decreasing vibrations that are often the cause of unexpected failures or crack propagations. Devices used in SHM and vibration damping must often be placed in remote areas, making renewable energy sources attractive for ensuring a constant power supply. The ‘Autonomous damage detection and vibration control systems’ (Advice) project was designed to develop ways of harvesting the mechanical energy inherent in structural vibrations to supply autonomous sensors used for SHM and vibration damping. The EU-funded researchers successfully designed, manufactured and tested a single energetically autonomous device that was both compact and light-weight. They integrated it into a complete system including the gateway and a central station for data collection and analysis. The entire system retained partial energy autonomy. The investigators then subjected the system to vibration patterns typical of those encountered by aircraft structures during flight. They subsequently characterised damage detection capability to assess safety and reliability. Along the way, they characterised complex parameters that influence identification of damage and subsequent localisation of the damage. The project's successful development of an autonomous wireless system for use in SHM and vibration damping should decrease airline maintenance time and cost and increase reliability. That’s good news for manufacturers and consumers alike.
