Adaptive Output Tracking Control Of Nonlinearly Parameterized System

Many physical systems such as biochemical processes and machines with frictions are nonlinearly parameterized systems with uncertainties. For such inherent nonlinear systems with uncertainties, it is impossible to achieve asymptotic output tracking. Therefore, the global practical output tracking of the systems is an important research topic both in theory and practice, that is to say the tracking error is made arbitrarily small within limited time by choosing appropriate design constants,.This paper presents a robust adaptive output feedback control scheme for a significant class of nonlinearly parameterized systems with uncertainties. The control scheme can realize the global output tracking of the uncertain nonlinearly parameterized systems, i.e. the output of the system can practically track the prescribed time-varying reference signals, reject the disturbances and maintain the internal stability of the closed-loop system. It can also reject the unmodeled dynamics without adding external signal. The scheme uses the output to form the control signal, with no need to estimate any parameters.The design of the output feedback robust adaptive tracking controller is based on the ideas of the input-to-state stable (ISS) Lyapunov functions and the technique of...