Adaptive Super‐Twisting Terminal Sliding Mode Observer‐Based Stabilizer for Uncertain Nonlinear Time‐Delay Systems With Unmatched Disturbances

• Published in: International journal of adaptive control and signal processing Vol. 39; no. 5; pp. 1091 - 1099
• Main Author: Pai, Ming‐Chang
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.05.2025; Wiley Subscription Services, Inc
• Subjects: adaptive super‐twisting terminal sliding mode observer; chattering phenomenon; Control systems; Disturbances; Linear matrix inequalities; linear matrix inequality (LMI); Simulation; Sliding mode control; terminal sliding mode controller; Twisting; unmatched external disturbances; Upper bounds
• ISSN: 0890-6327; 1099-1115
• DOI: 10.1002/acs.3994

ABSTRACT The aim of this paper is to propose a novel adaptive observer‐based stabilizer for a class of uncertain nonlinear time‐delay systems subject to unmatched external disturbances. A terminal sliding mode controller based on an adaptive super‐twisting terminal sliding mode observer is developed by using the linear matrix inequality (LMI) technique. Under the proposed scheme, the closed‐loop system converges to origin in finite time as the matching condition is satisfied and converges to the uniform ultimate bound in the effects of unmatched external disturbances. The design of the observer and the stabilizer does not require the upper bound of uncertainties and external disturbances. The chattering phenomenon is eliminated. The observer and the stabilizer can be efficiently designed from the solutions of LMIs. Simulation results illustrate the effectiveness of the proposed control scheme.