On the placement of active bars and optimal feedback gain in random adaptive structures for vibration suppression

This paper addresses active vibration control of adaptive structures using piezoelectric active structural elements with built-in sensing and actuation function. Optimal placement and feedback gain of these active members are important issues, which are discussed in this study. An efficient optimal placement strategy has been developed using minimum control energy dissipating over infinite time interval. Optimal location of active members has been found through minimization of total control energy dissipating over infinite time interval using Simulated Annealing (SA) algorithm. Moreover, the effect of structural randomness and random load in optimal feedback gain has been investigated. To accomplish this, a mathematical model with reliability constraints on the stress and displacement is developed and the optimal velocity feedback gain of active members, using probabilistic optimization technique, is obtained. Illustrative examples are presented to demonstrate the effectiveness of this methodology. It is shown that deterministic approach can not provide reliable optimum design values.