EXPERIMENTAL AND NUMERICAL STUDIES ON PERFORMANCE OF MACRO FIBER COMPOSITES FOR BEAM TWISTING APPLICATIONS

This paper presents the use of macro-fiber composites (MFC) as actuators for twisting control of pre-twisted beams, which is one efficient method of vibration suppression techniques of helicopter rotors. An MFC is a piezoelectric fiber composite which has an interdigitated electrode, rectangular cross-section and unidirectional piezoceramic (PZT) fibers embedded in the polymer matrix. An MFC actuator has much higher actuation performance, flexibility and durability than a traditional piezoceramic (PZT) actuator. This study showed that an MFC could be used as an actuator to change the displacement and twist tip-angle of a pre-twisted beam. In the test, an MFC patch was pasted on the beam’s upper surface to twist the pre-twisted beam actively. Different twist tip-angle changes of the pre-twisted beam were measured under a series of actuation voltages, and a good agreement was observed when experimental results were compared with numerical results. In addition, the actuation performance of MFC was compared with those of PZT4 and PVDF and the influence of anisotropic property of the MFC on its actuation performance was also studied. The experimental and numerical results presented in this paper show the potential of MFC for use in the vibration control of helicopter rotors.