Displacement characteristics of a monolithic PRESTO actuator with multiple active regions

In this paper the displacement properties of pre-stressed piezoelectric monomorphs with multiple bending elements are researched. Pre-stressed regions of PRESTO actuators were manufactured by screen-printing AgPd paste on commercial PZ21 discs with a diameter and thickness of 25 mm and 250 μm, respectively. The surface profile and out-of-plane displacement distribution of the actuators were measured with a profilometer and a fiber-optic vibrometer. Interference of adjacent bending elements was also measured and the effective piezoelectric d33 coefficients were determined. The results showed effective d33 values of ∼15,000 pm/V and ∼3500 pm/V, respectively, for Ø10 mm and Ø5 mm active regions in a 0.8 MV/m electric field. Interaction between the bending elements occurred, especially when the elements were closely arranged. The results enable further development of bending actuator matrices on a single disc for various applications where combined or individual actuation of several actuators is required.