Adaptive Fuzzy Tracking Control for a Class of Singular Systems via Output Feedback Scheme

The problem of adaptive fuzzy observer-based tracking control for nonlinear singular systems is considered in this article. The nonlinear singular systems are composed of two kinds of subsystems, differential subsystem and algebraic subsystem, which are coupled to each other. The systems can be nonstrict feedback structures. Through designing a new state observer and a linear controller, an error system with a tunable parameter is obtained. By constructing new one-sided Lipschitz conditions, the regularization and impulse-free conditions are proposed for the error system. With the help of the tunable parameter in the observer, we design an output feedback controller for the nonlinear singular systems to ensure that all states of the closed-loop system are bounded and the tracking observer errors remain in a neighborhood of the origin. Two examples are provided to illustrate the effectiveness of the presented method.