Observer-based decentralized robust H∞ output tracking control with preview action for uncertain and disturbed nonlinear interconnected systems

The problem of observer-based decentralized robust H-infinity output tracking control with preview action in a class of uncertain and disturbed nonlinear interconnected systems is investigated in this study. The considered interconnected system consists of several subsystems with nonlinear interconnections, parametric uncertainties, and external disturbances. Based on the augmented error system approach combined with Lyapunov stability theory and special matrix inequality linearization techniques, a sufficient condition for the existence of a decentralized observer-based robust H-infinity output feedback preview controller is derived for the original interconnected system in terms of linear matrix inequality (LMI) formulations. The gain matrices of the tracking controller and state observer are derived using only a one-step LMI procedure, which overcomes the drawbacks of some multistep iterative algorithms. Finally, the effectiveness of the proposed control scheme is validated using a numerical example.