Composite materials are a very important class of engineering materials with great properties and applications in a variety of complex structures. The correct design of such structures requires adequate analysis and, in particular, adequate and accurate models for simulation with numerical tools. Piezoelectric materials can convert mechanical energy into electric energy and vice-versa and are b...

This paper deals with active vibration control of a plate like smart flexible structure. This plate is equipped with several thin piezoelectric patches. Some of them are used as sensors and the others as actuators. They are optimally positioned and not collocated. The main goal of control is to reduce the most energetic vibrating modes. By using a state-space representation of a MIMO model of t...

This study investigates the applicability of time reversal concept in modern acoustics to structural health monitoring. A time reversal method has been adapted to guided-wave propagation to improve the detectability of local defects in composite plate structures. Specifically, wavelet-based signal processing techniques have been developed to enhance the time reversibility of Lamb wave in thin c...

The development of energy harvesting devices with piezoelectric transducers has been widely studied in the last decade. Most of previous studies considered a resonant cantilever beam with an attached tip mass and focused on the proper modeling of the cantilever device, design and optimization of electric harvesting circuit and nonlinear amplification of resonant vibration amplitude. However, fe...

|For crystal resonators, it is always desirable to calculate the electric properties accurately for application purposes. As an extension of the Mindlin plate theory based nite element analysis of crystal resonators, a new theory for the electroded plates is derived and the piezoelectrically forced vibrations are formulated and implemented in this paper in a manner similar to our previous work....

In this paper a new approach is presented to reduce vibrations for oneand two-dimensional mechanical structures, as beam or thin plates, by means of several piezoelectric transducers shunted with a proper electric network system. The governing equations of the whole system are coupled to each other through the direct and converse piezoelectric effect. More in detail, the mechanical equations ar...

Complex analysis of characteristic of underwater noise allows to find several features typical for underwater noise produced by ships as well as correlations between mechanical activity of ship’s mechanism and generated underwater sound. Their vibration activity might be reduced by applying active treatments utilising piezoelectric sensors and actuators. The paper explores the potentials of act...

This paper deals on converting mechanical impact on piezoelectric plate into electrical energy and using this harvested energy to power a wireless sensor node (WSN). Here we discuss on the power processing unit which consists of rectification, storage and regulation of voltage. The wireless sensor node senses the ambient vibrations around it and uses the harvested energy to send unique identifi...

A preliminary study of the feasibility of using piezo-transducer arrays, for detecting flaws in flat aluminum plates and steel tubing, is being performed at The University of Tennessee. The sensor arrays are designed for embedding in aluminum plates and brass tubes. Various forms of defects are placed on the test specimens. Preliminary experiments are carried out using both flat aluminum plate ...