Development of a wireless structural health monitoring system for aerospace application

Abstract

Structural health monitoring has a number of benefits to the aircraft industry, including improvements to safety, reduction in maintenance costs and potential weight savings. One reason why the aircraft industry is reluctant to apply such systems is the additional weight and integration issues caused by wiring them into the structures. The solution to this is the application of wireless technology, unfortunately this has its own problems and restrictions primarily due to the lack of available power, which would need to be sourced through energy harvesting. One structural health monitoring technique which has been investigated for aircraft use is Acoustic Emission, which enables the detection and localisation of damage within a structure. A major problem with the application of this technology using a wireless system is that adequate time synchronisation of each node would require significantly more power than is available through energy harvesting methods. This work presents the development of a technique to locate damage in complex aircraft structures, which was previously only applicable within simple plates. This method is used to successfully locate damage within fatigue testing on an aircraft wing panel. Furthermore, it can be applied within a wireless system without the need for highly accurate time synchronisation. The work includes the development of a prototype wireless system which applies a simplified version of the developed localisation technique. This hardware is tested on a range of composite and metal structures, including two aircraft wings. The accuracy of the results and the low power requirements of the system support further development in order to apply the system to an aircraft structure