An analytical and experimental study on adaptive active vibration control of sandwich beam

A novel composite sandwich beam with adaptive active control system is proposed for low-frequency vibration reduction, and the experimental investigation on adaptive closed-loop vibration control is carried out. The macro fiber composite (MFC) piezoelectric patches and filtered-x least mean square (Fx-LMS) algorithm are employed to construct the adaptive closed-loop control system. An improved analytical model considering the effects of MFC piezoelectric patches is proposed to calculate the vibration characteristics of the composite sandwich beam. It provides a theoretical basis for the design of adaptive control scheme. The accuracy of present analytical model is verified by the results of experiment and numerical simulation. The adaptive vibration control is implemented analytically and experimentally, and the results demonstrate that the low-frequency vibration of the composite sandwich beam can be greatly and quickly suppressed by the proposed adaptive closed-loop control system. Moreover, vibrations induced by complex multi-frequency excitation with different amplitudes can be effectively reduced by using the proposed adaptive control system. The novelty of this work lies in the proposed adaptive closed-loop vibration control system and improved analytical method for piezoelectric composite sandwich beam. The study provides a novel design of real-time control system for the low-frequency vibration of composite sandwich structures.