Nonlinear vibration control by semi-active piezo-actuator damping

A flexible beam model with bonded piezo-patches is taken as the study object. In order to suppress the disturbance vibration of the beam, the imposed voltage to the bonded piezoelectric elements is controlled. After the theoretical analysis for piezoelectric patches and beam structure, a bilinear form of the state space equation is derived. In this electromechanically coupled model, the imposed voltage control is related to the beam deformation state. Therefore, it is possible to realise the proposed semi-active control through a low cost approach. The concept of semi-active control comes from the fact of that only the gain of the imposed voltage is adjusted and the voltage direction is reverse to the deformation sensing. As a result, the control voltage is controlled only in two-phase planes. Here, nonlinear state feedback control theory is applied to design a controller and the proposed control approach is testified by numerical simulation.