T HE three-dimensional linear theory of elasticity is used to delineate the effect of the thickness, stiffness, and mass density of piezoelectric (PZT) layers on the ® rst ® ve natural frequencies of a simply supported graphite/epoxy laminated plate with PZT layers embedded in it. Platelike smart structures are usually made of PZT patches either embedded in or bonded to the bounding surfaces of...

Typically, the Electromechanical Impedance (EMI) technique does not use an analytical model for basic damage identification. However, an accurate model is necessary for getting more information about any damage. In this paper, an EMI model is presented for predicting the electromechanical impedance of a cracked beam structure quantitatively. A coupled system of a cracked Timoshenko beam with a ...

This study is aimed to explore efficiency problems of using PZT patches in active vibration control of beams. The PZT patches are surface-bonded as actuators and strain gages are used as sensors. Distributed moment forcing mode is adopted to derive the control authority of actuators. Uniform beam model is applied when the mass and stiffness of PZT patches are ignored. Stepped beam model is then...

Piezoelectric transducer (PZT) patches can be attached to structures in order to reduce vibration. The PZT patches essentially convert vibrational mechanical energy to electrical energy. The electrical energy can be dissipated via an electrical impedance. This paper introduces a method of implementing an arbitrary impedance using a current source and digital signal processor (DSP). The \synthet...

In the last decade, lead zirconate titanate oxide (PZT) thin-film actuators have received increasing attention because of their high frequency bandwidth, large actuation strength, fast response, and small size. The PZT film thickness is usually less than several microns as opposed to hundreds of microns for bulk PZT patches that are commercially available. As a result, PZT thin-film actuators p...

This research concerns the active vibration control of a three-story model structural frame by using piezoceramics smart materials, in particular lead zirconate titanate (PZT), in the form of patches. These PZT patches are surface-bonded on the structure and function as actuators and sensors. To assist the control design, system identification is first performed. To excite the frame for identif...

In this paper, a feedback control mechanism and its optimization for rotating disk vibration/flutter via changes of air-coupled pressure generated using piezoelectric patch actuators are studied. A thin disk rotates in an enclosure, which is equipped with a feedback control loop consisting of a micro-sensor, a signal processor, a power amplifier, and several piezoelectric (PZT) actuator patches...

Flexible piezoelectric PZT/fabric composite material is pliable and tough in nature which is in a lack of traditional PZT patches. It has great application prospect in improving the sensitivity of sensor/actuator made by piezoelectric materials especially when they are used for curved surfaces or complicated conditions. In this paper, glass fiber cloth was adopted as carrier to grow PZT piezoel...

In this paper, the active buckling control of smart functionally graded (FG) plates using piezoelectric sensor/actuator patches is studied. A simply supported FG rectangular plate which is bonded with piezoelectric rectangular patches on the top and/or the bottom surface(s) as actuators/sensors is considered. When a constant electric charge is imposed, the governing differential equations of mo...