Optimal unimorph and bimorph configurations of piezocomposite actuators for bending and twisting vibration control of plate structures

Optimal configuration of anisotropic piezocomposite actuators is investigated for vibration control of flexible structures. Actuation effects of the actuators in unimorph and antisymmetric angle-ply bimorph configurations are analyzed. Dynamic equations of the piezo-actuated plate are established using finite element method. The locations and lead zirconate titanate fiber orientations of actuators are optimized simultaneously to improve vibration control performance of a plate. The optimization criterion is presented based on controllability Gramian matrix of the system. The properties of macro-fiber composite are used in the simulations of the actuators. The optimal unimorph and bimorph configurations of actuators are presented for three cases: bending control, twisting control, and coupled bending–twisting control. The results indicate that both optimal locations and fiber orientations are different for bending control and twisting control. A trade-off between control authority for bending and torsional modes can be found in coupled bending–twisting control. The actuators should be placed in the regions of high average strain of the interested modes with appropriate fiber orientations. Special piezocomposite actuators with optimal fiber orientations can be used to achieve improved coupled bending–twisting vibration control performance.