Cortez, Nicolás E.Vieira Filho, Jozué [UNESP]Baptista, Fabricio G. [UNESP]2014-05-272014-05-272013-01-01Structural Health Monitoring, v. 12, n. 1, p. 14-22, 2013.1475-92171741-3168http://hdl.handle.net/11449/74244This article presents a new method to detect damage in structures based on the electromechanical impedance principle. The system follows the variations in the output voltage of piezoelectric transducers and does not compute the impedance itself. The proposed system is portable, autonomous, versatile, and could efficiently replace commercial instruments in different structural health monitoring applications. The identification of damage is performed by simply comparing the variations of root mean square voltage from response signals of piezoelectric transducers, such as lead zirconate titanate patches bonded to the structure, obtained for different frequencies of the excitation signal. The proposed system is not limited by the sampling rate of analog-to-digital converters, dispenses Fourier transform algorithms, and does not require a computer for processing, operating autonomously. A low-cost prototype based on microcontroller and digital synthesizer was built, and experiments were carried out on an aluminum structure and excellent results have been obtained. © The Author(s) 2012.14-22engdirect digital synthesizerelectromechanical impedancemeasurement instrumentsmicrocontrollerpiezoelectric transducersStructural health monitoringAluminum structuresAnalog to digital convertersCommercial instrumentsDifferent frequencyDigital synthesizersDirect digital synthesizerElectromechanical impedanceExcitation signalsFourier transform algorithmsLead zirconate titanateMeasurement instrumentsOutput voltagesResponse signalRoot Mean SquareSampling ratesStructural healthStructural health monitoring systemsDamage detectionMicrocontrollersPiezoelectric transducersSemiconducting lead compoundsComputer operating systemsArtigo10.1177/1475921712461163WOS:000325812300002Acesso restrito2-s2.0-848722808890534385574959094