A robust output-feedback control scheme based on composite nonlinear feedback in singular uncertain delayed models

Relying on composite nonlinear feedback, an output-feedback controller is robustly addressed in the singular models with uncertainties, disturbances and time-delays. For this purpose, an observer-based compensator is utilized to realize the purpose. In the presence of disturbance and uncertainty, it is demonstrated that the tracking error and the states of the overall system are ultimately bounded. Moreover, the asymptotic stability would be specifically established without the external disturbance and uncertain terms. Employing the linear matrix inequality, the control design is translated into an optimization problem. Hence, in solving such an optimization issue, the coefficients of the estimator and the control law are determined simultaneously. Some simulations are provided to show the advantages of the planned strategy compared to a similar one.