Prescribed‐Time Tracking Control of Nonlinear Strict Feedback Systems With Time‐Varying Parameters and Disturbances Under Full‐State Constraints

ABSTRACT This article proposes an adaptive dynamic surface prescribed‐time control strategy for uncertain full‐state constrained nonlinear systems subject to time‐varying parameter uncertainties and external disturbances. A smooth nonlinear term with a unified adaptive‐gain law is first constructed to simultaneously enable compensation for the time‐varying parameter uncertainties and external disturbances. Subsequently, by employing the dynamic surface control and the constraint transformation function, an appropriate prescribed‐time controller framework with an improved first‐order filter is given, where the complexity explosion can be avoided and all the system states can be restricted to the predefined bounds. Rigorous theoretical analysis ensures both the prescribed‐time transient performance and steady performance of the tracking errors while achieving the full‐state constraints. Finally, the effectiveness of the proposed controller is verified by two simulation examples.