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

Abstract

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.

Experimental analysis of the feasibility of low-cost piezoelectric diaphragms in impedance-based SHM applications

“…where Z E (ω) is the electrical impedance of the PZT patch at angular frequency ω, which should vary within an appropriate range; Z P (ω) and Z S (ω) are the mechanical impedances of the PZT patch and the monitored structure, respectively; a is a geometric constant that depends on the shape and size of the patch; j is the unit imaginary number; and T 33 , d 31 and s E 11 are the same as defined before considering a one-dimensional assumption.…”

“…In the past, impedance measurements were typically performed with expensive commercial impedance analyzers, which have many features not required for the EMI method. Many researchers have proposed alternative measurement systems [12,30,31] to simplify the measurement of impedance and lower its cost.…”

“…Typically, the detection and quantification of damage is performed by comparing two impedance signatures using damage indices; thus, the reproducibility of the impedance signatures is important to avoid false-positive diagnoses. Therefore, the last test examined the reproducibility of the results obtained using the piezoelectric diaphragms by measuring the impedance signatures The electrical impedance signatures were obtained using the measurement system proposed in [31] with a multifunction DAQ device (NI-USB-6361) operating at a sampling rate of 2 MS/s and a personal computer running LabVIEW (National Instruments, Austin, Texas, USA). The transducers were excited with a chirp signal at 1 V of amplitude, and the signatures were obtained in the frequency range of 0-500 kHz in steps of 2 Hz.…”

Modeling, Simulation, Experimentation, and Compensation of Temperature Effect in Impedance-Based SHM Systems Applied to Steel Pipes

“…There are many methods according to the stages of SHM systems, but in the present work, the focus is the damage detection by means of the electromechanical impedance technique (EMI), which is based on low cost PZT (Pblead Zirconate Titanate) piezoelectric transducers. Such transducers are extremely sensitive in detecting local damage [2,4,6,7] and allow the implementation of non-invasive SHM systems. The basic principle of the EMI technique is to monitor the changes in the mechanical impedance of a structure, caused by alterations in its dynamic response, due to the presence of damage or even due to temperature variation.…”

Design and Implementation of the ZigBee Wireless Sensor Network Based on ARM

“…While, the development of wireless sensor network has greatly promoted the people's ability of information acquirement and perception, which can effectively acquire various information in the physical world, and make such information be widely used in national defense, industrial control, intelligent medical treatment, modern agriculture, etc. The ZigBee technology is a communication protocol standard that is developed based on small wireless networks [1], and has great application prospect in smart home and commercial building automation, as the ZigBee protocol matures gradually, especially in recent years [2].…”