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The paper investigates the active vibration control (AVC) of flexible thin-walled structure using dielectric elastomer (DE) actuator. It is proposed to bond directly DE film to the surface of flexible thin-walled structure so as to actively control structural vibration through in-plane actuation of DE film. This kind of actuator is referred to as planar DE actuator, which has advantages such as small additional mass and easy installation, and thereby can realize more easily active vibration control of flexible thin-walled structures in comparison with DE actuators with columnar configuration. In order to reduce control voltage, a multi-layer planar DE actuator (MPDEA) is further developed. Based on the Hamilton principle and the constitutive equation of DE material, the governing equation in the form of finite element for a cantilever polycarbonate beam with MPDEA is derived. Simulated and experimental studies are carried out on active vibration control of flexible thin-walled beam using MPDEA with different layers. The results show that MPDEA can achieve good vibration control effect for flexible thin-walled beam. Especially, the driving voltage can be greatly reduced by employing MPDEA. Moreover, a nonlinear compensation model is proposed to suppress the control spillover caused by nonlinear actuating properties of MPDEA. The simulated and experimental results of AVC of cantilever flexible thin-walled beam with the compensation model show that the overall control performance can be improved due to noticeable restrain of the control spillover. [ABSTRACT FROM AUTHOR]

An active vibration control scheme was proposed based on Macro Fiber Composite (MFC) actuators for the bending and torsional vibration control of large flexible lightweight wing structures. Firstly, a finite element modeling and modal analysis of a flexible wing are carried out. Further, the number, type, and location distribution of the MFC actuators bonded on the supported beam of the wing are designed. Then, the actuated characteristics of the two kinds of MFC actuators required for bending and torsional vibration controls was theoretically analyzed. The simulation model of the overall vibration control system was also finally obtained. Finally, through ANSYS simulation analysis, the vibration control effect of the current control system on the first two-order low-frequency modal response of the wing structure is given. The simulation results show that the proposed active vibration control scheme has specific feasibility and effectiveness. [ABSTRACT FROM AUTHOR]

A bilateral piezoelectric stack actuator (BPSA) is introduced, and its actuated property is also analyzed. Usually, a piezoelectric stack can only undertake significant compressive loads but cannot tolerate tension, while this new actuator is able to generate obvious bilateral actuated outputs. The actuated principle of the new actuator is analyzed firstly. The linear and nonlinear models are also built up. The latter is to analyze the piezoelectric hysteresis based on the classical Preisach model. Moreover, the effect of the preload on the actuator is considered. By comparison with the experiment results, the Preisach model is valid for the present actuator. [ABSTRACT FROM AUTHOR]

Abstract: The effect of a laminated polyvinylidene fluoride (PVDF) actuator is analyzed when partially covering a paraboloidal shell. Models of control forces are established using the thin flexible shell theory and the membrane approximation. Analytical expressions of actuating forces and moments are derived and a parametric study is conducted to evaluate the effects of the physical properties of the actuator on the control forces. To verify the model, experiments were carried out on actuation and open-loop vibration control of a paraboloidal antenna with a much smaller actuator. The experimental results agree well with those obtained analytically. The results indicate the following: The laminated PVDF actuator (LPA) can provide effective control forces with low voltages. The control forces consist of actuating forces and moments, but the effect of the normal actuation force distribution is much greater than that of the actuation moments in controlling the normal vibration. The larger the curvature radius of the paraboliodal shell, the smaller the magnitudes of the required actuating forces. The magnitudes of actuating forces are approximately linear with the number of PVDF layers. [Copyright &y& Elsevier]