Fixed-Time Stabilization of High-Order Uncertain Nonlinear Systems: Output Feedback Control Design and Settling Time Analysis

• Published in: Journal of systems science and complexity Vol. 36; no. 4; pp. 1351 - 1372
• Main Authors: Guo, Chaoqun, Hu, Jiangping
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2023; Springer Nature B.V
• Subjects: Closed loops; Complex Systems; Control; Control systems; Feedback control; Homogeneity; Mathematics; Mathematics and Statistics; Mathematics of Computing; Nonlinear systems; Operations Research/Decision Theory; Output feedback; Settling; Statistics; Systems Theory; Upper bounds; homogeneity approach; settling time; Fixed-time observer; high-order uncertain system; output feedback control
• ISSN: 1009-6124; 1559-7067
• DOI: 10.1007/s11424-023-2370-y

This paper is devoted to stabilizing the high-order uncertain nonlinear system in a fixed time by output feedback control. First, a novel settling time solution method is proposed by establishing an indirect double system and using the comparison principle. Then a fixed-time observer and a neural networked based adaptive law are constructed to estimate the state and the unknown disturbance for the high-order uncertain nonlinear system. Furthermore, a fixed-time output feedback controller is proposed via the homogeneity technique. The upper bound of the settling time is analyzed for the closed-loop system under the proposed output feedback control. Finally, simulation examples are given to illustrate the effectiveness of the theoretical results.