An intelligent active-passive vibration absorber using hierarchical fuzzy approach

It has been shown that piezoelectric materials can be used as highly promising for application such as passive electromechanical vibration absorbers by shunting them with electrical networks. However, these passive devices have limitations that restrict their practical applications. The main goal of this work is to develop a novel approach for achieving a high performance adaptive piezoelectric absorber - an active-passive hybrid configuration. Owing to the adaptive capability of fuzzy inference systems, its applications to the active control are immediate. This investigation addresses the first application of the concept of hierarchy for controlling fuzzy systems in such an active-passive absorber. One of the main advantages of using a hierarchical fuzzy system is to minimize the size of the rule base by eliminating "the curse of dimensionality". Although the performance of the optimal passive absorber is already much better than the original system (no absorber), the intelligent active-passive absorber can still outperform the passive system significantly. The fuzzy control method appears quite useful as regards reliability and robustness.