Vibration control of unknown flexible beam structures

Two approaches, namely, state space-principal component analysis (SS-PCA) and fuzzy logic-genetic algorithms (FL-GAs) controllers are introduced for constraining the transient motion of flexible structures. These two techniques require no prior knowledge about the physical modeling of such structures. The SS-PCA has the capability, among all the other available methods, of providing an estimation of the characteristics of the system under consideration from measured displacement outputs. Excellent control was achieved with both proposed techniques, though quite better results were obtained when applying FL-GAs. However, in the online processing, the FL-GA was found to need more computational time when compared with the SS-PCA.