Closed loop observers bundle for uncertain biotechnological models
Abstract
We propose nonlinear observers for a class of biotechnological processes. These observers are an extension of the asymptotic observers (observers with unknown inputs) devoted to biotechnological systems for which some parts of the model are unknown. We take benefit of the additional outputs which are (non linear) functions of the state to design a closed loop observer. The global convergence of these nonlinear observers is proven. We use then these observers to design interval based observers which predict the intervals in which the state is lying. We run in parallel a broad set of interval observers and we select the best ones. The method is illustrated with a model describing the bioconversion of a substrate using microorganisms in a bioreactor.