In Search of Suitable Control Methods for Semi-Active Tuned Vibration Absorbers

Abstract

The main purpose of this study is to identify a suitable control method for semi-active tuned vibration absorbers (TVAs) in structural vibration applications. Four control policies are considered. The semi-active control schemes include the following: velocity-based, on-off groundhook control (on-off VBG); velocity-based, continuous groundhook control (continuous VBG); displacement-based, on-off groundhook control (on-off DBG); and displacement-based, continuous groundhook control (continuous DBG). A force-excited model that can be representative of many structural systems is adapted as the baseline model for our analysis. Each of the control policies is applied to the baseline model coupled with a TVA. In order to equally evaluate the control policies, the TVA parameters are optimized according to each policy using numerical optimization techniques. The optimal design parameters are obtained based on minimization of peak transmissibility. The performances of each of the optimized cases are then compared along with the equivalent passive model using the peak transmissibility criteria. The results indicate that all of the semi-active peak transmissibilities are lower than those of the passive, implying that the semi-active TVAs are more effective in reducing vibration levels. The results further indicate that on-off DBG performs the best among the considered control polices.