Unstructured uncertainty models are commonly used within robust control framework to cover unmodeled dynamics, particularly at high frequency. The resulting uncertain linear time invariant (LTI) models (i.e. models comprised of an LTI nominal model and an uncertainty model) are then used in robust controller synthesis procedure and have significant influence on the controller performance. This paper proposes a novel procedure for constructing unstructured uncertainty models for a class of mechanical vibration systems comprised of a number of interconnected (coupled) vibration subsystems. As the result of the proposed procedure, we are able to significantly reduce conservatism of the resulting uncertain LTI models of the individual subsystems, thus improving the performance of subsequent robust control strategies. We illustrate the results on a numerical example comprised of a series of simply-supported beams coupled with a set of springs.
展开▼
