Design and implementation of wireless sensor networks for impedance-based structural health monitoring using ZigBee and Global System for Mobile Communications

This article presents the design and implementation of a novel wireless structural health monitoring system based on the electromechanical impedance principle. The proposed system is a wireless low-power scalable sensor network composed of multiple sensor nodes and a link node used as master to establish communication with the remote monitoring center (host node and server). The link node communicates with the remote monitoring center through a Global System for Mobile Communications/General Packet Radio Services network and with other sensor nodes through a ZigBee network. Each sensor node is a portable and autonomous structural health monitoring core based on microcontroller, digital synthesizer, and transceiver ZigBee. The identification of damage is performed by simply comparing the variations in root mean square voltage obtained from piezoelectric transducers, such as lead zirconate titanate patches, bonded to the structure. The lead zirconate titanate patches are excited on a wideband frequency range, and it is not necessary to compute the electromechanical impedance. The proposed system was built and experiments were carried out on an aluminum structure, and excellent results have been obtained. Our contribution ranges from the hardware to the graphical front end.