Dynamic response of simply supported beams excited by piezoelectric actuators

Abstract

The use of piezoelectric devices for the purposes of active noise or vibration control has become attractive in recent times. These small, power to weight efficient devices have had some success in active vibration control; however, the force transfer mechanism by which they interact with the structure to which they are attached needs to be understood to optimise the efficiency of their use. Various modelling approaches have been used over the past six (6) years to try and understand the force transfer mechanism in beams and plates, and in this work an adaptation of a published model is presented, and compared with experimental data and other published models. The force transfer mechanism between the piezoelectric actuator and the beam is found to be dependent upon the impedance of the beam. At resonance, the free edge condition of the piezoelectric actuator does not affect the strain field close to the free edge. Away from resonances, the force transfer mechanism is different and less efficient, and the free edge condition of the piezoelectric actuator does affect the strain field close to the free edge of the actuator. Further experimental work, investigating the power flow from the piezoelectric actuators to the beam, emphasises some of the differences found between the theory and experiments, and between the performance of piezoelectric actuators and electrodynamic actuators