Output tracking control of strict-feedback non-linear systems under asymmetrically bilateral and time-varying full-state constraints

• Published in: IET control theory & applications 2020-01, Vol.14 (1), p.156-164
• Main Authors: Sun, Yawen, Gao, Shigen, Ning, Lingbin, Dong, Hairong, Ning, Bin
• Format: Article
• Language: English
• Subjects: adaptive control; approximation‐free backstepping control scheme; asymmetrically bilateral time‐varying full‐state constraints; Brief Paper; closed loop systems; closed‐loop system; control nonlinearities; control system synthesis; feedback; linear systems; nonlinear control systems; nonlinear mapping; state feedback; state feedback output tracking control problem; strict‐feedback nonlinear systems; strict‐feedback system; uncertain pure‐feedback system; uncertain systems
• ISSN: 1751-8644; 1751-8652; 1751-8652
• DOI: 10.1049/iet-cta.2019.0399

The state feedback output tracking control problem is investigated for a class of uncertain non-linear strict-feedback system subject to asymmetrically bilateral and time-varying full-state constraints. Non-linear mapping is employed to deal with full-state constraints and the system is transformed into an uncertain pure-feedback system. For the transformed system, an approximation-free backstepping control scheme is proposed by using performance function rather than employing any estimator. It is shown that the proposed control strategy can guarantee that all signals in the closed-loop system are bounded and the tracking errors can be made arbitrarily small by choosing proper control gains. Meanwhile, the states are set within the asymmetrically bilateral and time-varying full-state constraints. At last, two simulation examples are obtained to demonstrate the feasibility and effectiveness of the proposed control algorithm wherein the practical system for metro is considered.