Multiple piezoelectric segments in structural vibration control

This paper presents active damping of structural vibration of a simply supported beam excited by a time-dependent concentrated force. The control is realized by means of multiple piezoelectric patches working as collocated sensors and actuators. The attention is focused is on suppression of low vibration modes. The control low is based on the velocity as well as proportional-velocity feedback. To simplify the analysis, dynamic responses of the system are obtained by adopting the static model of piezoelement-substructure coupling which is formulated assuming the perfect bonding and negligible bending stiffness and mass of distributed sensors and actuators. An influence of spatial arrangement of sensor/actuator pairs on active damping efficiency is numerically investigated. The effective set of sensor/actuators with the controllers incorporating the proportional-velocity actions is proposed. Some results based on a simple model of the mechanical system are compared with those obtained in the case when the activated section is modelled as a laminated beam, and when the dynamic model of actuator-beam interaction, which includes the finite-thickness shear bonding layer, is applied. This comparison shows that a sufficiently stiff glue layer between the actuator and basic structure, and thin piezoelements (when compared to the beam thickness) allow for using of the static coupling model.