Characteristics of shear mode piezoelectric actuators

Characteristics of cantilever shear mode piezoelectric actuator have been investigated. In this actuator configuration, soft PZT ceramic plate was poled along length and driven across its thickness, with one end mechanically clamped and the other free. Experimental results indicated that relative large tip displacement can be obtained through nonlinear piezoelectric response at high driving field. Due to lateral shear force, mechanical bending also contributes to the tip displacement of shear mode actuator. The fundamental bending resonant frequency was observed in the frequency range from 150 Hz to 600 Hz, depending on thickness and length of actuator. We also found that the resonant frequency of bending vibration is dependent on the driving field because of elastic nonlinearities. Two layer and multilayer shear mode actuators were also developed to reduce the driving voltage, while shifting the bending resonance to higher frequency range by increasing the total thickness of actuator.