F. Charette et al., ASYMMETRIC ACTUATION AND SENSING OF A BEAM USING PIEZOELECTRIC MATERIALS, The Journal of the Acoustical Society of America, 96(4), 1994, pp. 2272-2283
This paper presents the development of a theoretical model and an expe
rimental study for the response of a beam actuated by a ceramic piezoe
lectric on one side with a PVDF piezoelectric on the opposite side act
ing as a sensor. The two piezoelectric are of different types, may be
of arbitrary length, and are positioned independently along the beam.
Since the actuation is done by a single piezo on one side of the beam,
an asymmetric excitation is applied to the beam that causes simultane
ously extensional and flexural displacements. Both piezoelectric eleme
nts are considered perfectly bonded to the beam. The variational appro
ach with Hamilton's principle is used to develop the theoretical model
. This formulation, which is energy based, allows one to consider any
boundary conditions at the ends of the beam and to take into account t
he dynamic effects (mass loading and stiffness) of both piezos on the
beam response ignored in existing models. Experimental results are pre
sented for the free-free boundary conditions. Those results show good
agreement with the theoretical model and prove that the piezo's modify
the mode shapes and natural frequencies of the beam. The changes in t
he mode shapes can be of vital importance in some applications.