Adaptive sliding mode control of a class of nonlinear systems with artificial delay. Issue 18 (December 2017)

• Record Type: Journal Article
• Authors: Roy, Spandan; Kar, Indra Narayan
• Is Part Of: Journal of the Franklin Institute. Volume 354:Issue 18(2017)
• Page Start: 8156
• Page End: 8179
• Publication Date: 2017-12
• Subjects: Science -- Periodicals; Technology -- Periodicals; Patents -- United States -- Periodicals; 505
• DOI: 10.1016/j.jfranklin.2017.10.010
• Languages: English
• ISSNs: 0016-0032

Abstract

Abstract: In this paper, an adaptive-robust control (ARC) strategy, christened as Adaptive Time-delayed Sliding Mode Control (ATSMC) is presented for trajectory tracking control of a class of uncertain Euler-Lagrange systems. The proposed control framework brings together the best features of the switching control logic and time-delayed logic. ATSMC uses artificial time delay to approximate the unknown dynamics through time-delayed logic, and the switching logic provides robustness against the approximation error. The adaptation law for the switching gain of the conventional ARC methodologies suffer from over- and under-estimation problems. The novel adaptive law of ATSMC alleviates the over- and under-estimation problems of switching gain. Moreover, a new design methodology and stability criterion for time-delayed control is proposed which provides an upper bound on the allowable delay time. Experimental results of the proposed methodology using a nonholonomic wheeled mobile robot (WMR) is presented and improved tracking accuracy of the proposed control law is noted compared to time-delayed control and conventional adaptive sliding mode control.