Coprime factor based closed-loop model validation applied to a flexible structure

This paper addresses the problem of checking the consistency of experimental closed-loop frequency-domain data with uncertainty models that are structured using coprime factorizations. The uncertainty models presented in this paper use the knowledge of a stabilizing feedback controller to structure and formulate the uncertainty on a model. Subsequently, the controller dependent coprime factor uncertainty model can be used to formulate model (in)validation tests on the basis of closed-loop data. The model (in)validation is performed on sample data from a flexible structure to illustrate the presented model validation results. An open-loop based uncertainty model is also used to demonstrate the benefits of closed-loop uncertainty modeling over open-loop uncertainty modeling.