Finite-gain based adaptive predefined-time control for a class of strict-feedback systems subject to output constraints☆

This paper investigates the predefined-time control problem for a class of nonlinear systems subject to unmatched parametric uncertainties and asymmetric output constraints. A finite-gain based adaptive control scheme is proposed, with which the system is regulated to the equilibrium within the prescribed finite time and the asymmetric constraint requirements on the output are not violated during operation. This is achieved mainly by establishing a new predefined-time stability lemma, which allows the technical difficulty arising from the finite gain based predefined-time controller design and stability analysis to be overcome. In addition, a new universal barrier function is employed to address anticipated constraint requirements on the system output, which enables the performance boundary to be uniform with respect to the initial condition. Two simulation examples are given to confirm the effectiveness of the proposed control scheme. (c) 2024 Published by Elsevier Ltd.