Application of Hinf Active Vibration Control Strategy in Smart Structures

In this study, H∞ controllers were designed and implemented on a smart beam. The smart beam consisted of an aluminum beam modeled in cantilevered configuration with eight surface bonded piezoelectric lead-zirconatetitanate (PZT) patches. The study used ANSYS® (v5.6) for the structural modeling of the smart beam. The system models were obtained through the system identification made on the experimental beam data. The H∞ active vibration controllers, which effectively suppressed the sinusoidally excited, in-vacuo forced vibrations of the smart beam due to its first two flexural modes, were then designed by using MATLAB® tool-boxes and implemented. During the experiments both the strain gauge and laser displacement sensor were used as vibration sensors. The theoretical and experimental characteristics were compared to verify the developed models. The effects of the higher beam vibrational modes and the damping were included in the system model as uncertainties. It was shown that H∞ active vibration controllers were very effective in suppressing the sinusoidally excited, in-vacuo forced vibrations of the smart beam. Some preliminary studies on the modelling and verification of a smart fin were also presente