Abstract
The combined effects of passive and active control on the vibration control of a com posite laminated plate with piezoelectric sensors/actuators are investigated. Finite element formula tion and modal analysis are presented. Classical laminated plate theory with the induced strain ac tuation and Hamilton's principle are used to formulate the equation of motion of the system. The total charge developed on the sensor layer is calculated from the direct piezoelectric equation. The equa tions of motion and the total charge are discretized with 4-node, 12-degree of freedom quadrilateral plate bending elements. The stiffness and damping property changes of composite structures by varying the layer angles are used as a passive control method. Piezoelectric sensors/actuators with negative velocity feedback control are used as an active control method. By numerical simulation, the effects of stiffness and damping property changes of composite structures and the effects of sen sor/actuator division on the response of the structure and the performance of the vibration control are investigated. Since active control and passive control affect each other, the active control and the passive control should be considered simultaneously in designing the efficient adaptive structures.