Optimizing the Thickness of Piezoceramic Actuators for Bending Vibration of Planar Structures

An analytical approach is proposed to optimize the thickness of piezoceramic (PZT) actuators bonded on structures for active shape, noise, or vibration control. The optimal thickness corresponds to maximal mechanical coupling between the PZT actuator and the substrate. The analysis is carried out for a planar geometry, considering a square simply supported flexural plate with a square and a centered PZT actuator bonded either in symmetric or asymmetric configuration. Optimal thicknesses obtained from explicit analytical expressions are compared with finite element (FE) results for various substrate thicknesses and for various values of actuator coverage ratio. Static and dynamic strain profiles through the thickness of the plate—actuator system are plotted. Laboratory experiments are carried out on aluminum and steel plates with free and clamped boundary conditions to verify the analytical and FE predictions in terms of optimal PZT actuator thickness.