Optimum Design Process of Vibration Absorber Via Imperialist Competitive Algorithm

This paper deals with the optimum design of vibration absorbers utilized to reduce undesirable random vibrational effects that are originated in linear structures. Analytical expressions, for the case of nonstationary white-noise accelerations, are derived. The criterion is different from most conventional optimum design criteria, since it is based on minimizing the displacement or the acceleration variance of the main structure responses, without considering performances required against failure. In this study, in order to control the structural vibrations induced on a mechanical structure excited by nonstationary based acceleration random process, the MOO (multi-objective optimum) design of a vibration absorber has been developed in a typical seismic design problem. This has been performed using the modern imperialist competitive optimization algorithm for multi-objective optimization. Results demonstrate the importance of this method and show that the multi-objective design methodology provides a significant improvement in performance stability, giving a better control of the design solution choice. A numerical example of a vibration absorber for a multi degree of freedom (DOF) system is developed and the results are generated and compared for higher (DOF) systems using two types of modeling. Finally, the results of each of the two types are discussed.