A compact piezoelectric stack actuator and its simulation in vibration control

To exert strong actuating power of piezoelectric stack and facilitate the incorporation of piezoelectric stack and host structure for vibration control application, a Π shape piezoelectric stack actuator (PISA) was designed. One piezoelectric stack and a Π shape metal pedestal were assembled together by a screw to build a PISA. Formula for calculating the actuating moment output of PISA was derived. Then PISA was applied in a vibration control system of a cantilever beam example. Thermal-elasticity analogy theory was applied in the modeling of the piezoelectric active vibration control system. Positive position feedback (PPF) control, linear quadric regulator (LQR) control, and neural network predictive (NNP) control strategies were adopted to perform the first bending mode vibration control of the beam. Simulation results indicate that with this new actuator and the PPF or LQR control strategy, the first bending mode amplitude of the cantilever beam can be reduced by about 60% or 79%while using the NNP control strategy the amplitude can be suppressed by more than 95%These results indicate that PISA can sever as a high efficiency actuator in structural vibration control application.