FURTHER-STUDIES OF THE DYNAMIC-RESPONSE OF A SIMPLY SUPPORTED BEAM EXCITED BY A PAIR OF OUT-OF-PHASE PIEZOELECTRIC ACTUATORS

The response of a simply supported beam excited by a pair of out-of-phase piezoelectric actuators perfectly bonded to the beam surface, is modelled analytically and measured experimentally. The analytical model follows the approach of Pan et al. (1992) and corrects errors in that work. Other analytical models are reviewed and it is shown that two equivalent force transfer mechanisms, either two counteracting uniform surface strain distributions or two counteracting uniform moment distributions, can be used in the models to describe the beam response at resonance, for in this condition, the free edge condition of the piezoelectric actuator does not affect the strain field. The analysis shows that this current model agrees with other modelling approaches, but experiments show that away from resonance, significant differences in the beam response are found due to the influence of the free edge condition of the piezoelectric actuator. However, none of the previously published papers nor the model discussed in this paper account for the force transfer mechanism due to the free edge of the piezoelectric actuator. The modelling technique postulated in this paper however will readily lend itself to be used when a more accurate extensional strain model is available.