Augmented damping of a piezo-composite beam using extension and shear piezoceramic transducers

The present study describes a comprehensive investigation performed to study the effects of piezoceramic materials on the augmented damping of vibrating piezo-composite beams. The augmented active damping is obtained by using an actuator and a sensor made of piezoceramic materials, acting in a 'closed-loop'. Transferring the accumulated voltage on the sensor layer to the piezoelectric actuator layer causes the beam to actively damp-out its vibrations. The voltage transferred from the sensor to the actuator has to be amplified through a feedback gain. An exact mathematical model based on a first order shear deformation theory (FSDT) was developed and described in order to study the effect of all four possible piezoelectric 'closed-loop' combinations (EE, SS, ES and SE). The first two combinations use only one piezoelectric mechanism, extension or shear, as both sensors and actuators, while the other two, use combined piezoelectric mechanisms, extension and shear. Using the present model, both natural and damped vibrations were calculated. A comprehensive parametric investigation was performed to study the required feedback gain, G, for each piezoelectric combination, and the effect of piezoelectric materials on damping higher frequencies. (c) 2005 Elsevier Ltd. All rights reserved.