In the present study, fuzzy control of vibration of a hybrid smart composite beam actuated by electro-rheological fluids (ERF) and piezoceramics actuators is investigated. A carbon fiber reinforced plastics (CFRP) cantilevered beam containing ERF with bonded piezoceramics is prepared and vibrated forcibly with sinusoidal external excitation. Fuzzy model of controlled element containing two actuators is formed in consideration of intense nonlinearity in ERF actuator. Parameters of membership functions and linear equations of fuzzy inference system in Sugeno style are identified by using a hybrid neuro-fuzzy system. Fuzzy controller for vibration control of the composite beam is designed based on the fuzzy model by using the modern control theory. The effect of vibration control system with a fuzzy controller is verified by simulation and experiment.

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This paper describes cure and health monitoring of glass fiber reinforced plastics (GFRP) textile composites both during a resin transfer molding (RTM) process and in loading tests. Carbon fiber reinforced plastics (CFRP) textile composites also were used for a comparative study. Fiber Bragg grating (FBG) fiber optic sensors were embedded in FRP to monitor internal strain. From the results of cure monitoring, it was found that the embedded FBG sensors were useful to know when cured resin constrained fibers. It also appeared that specimens were subjected to friction stress resulted from difference of coefficient of thermal expansion between FRP and a stainless steel mold in cooling process of RTM molding. After the molding, tensile and fatigue tests were conducted. The results of tensile tests showed that output of the embedded FBG sensors agreed well that of surface-bonded strain gauges despite deterioration of reflected spectra form the sensors. From the results of fatigue tests, the FBG sensors showed good status until 100,000 cycles when specimens had no damage. From these results, it can be concluded that embedded FBG sensors have good capability of monitoring internal strain in textile FRP both during RTM process and in service.

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In the present study, the vibration control of a hybrid smart composite beam actuated by both electro-rheological fluids (ERFs) and piezoceramic actuators is investigated. A carbon fiber reinforced plastics beam, including interleaved ERF and bonded piezoceramics, is prepared and tested under sinusoidal external excitations. Four kinds of feedback control strategies for both ERF and piezoceramic actuators are adopted in order to suppress the deflection at the free end of the cantilevered composite beam. The optimum combination of these control strategies for two types of actuators is discussed when the two actuators operate simultaneously.