Tracking Control of a Two-Wheeled Mobile Robot Using Integral Sliding Mode Control and a Linear Quadratic Regulator

Abstract

In this work, an effective control framework is proposed for a two-wheeled mobile robot (TWMR) operating under time-varying disturbances and uncertain system parameters. To enhance robustness against these uncertainties, an integral sliding mode control (ISMC) method is adopted. A mathematical model of the TWMR is obtained in the state form, and an ISMC law is designed. The proposed control law comprises two terms: a nominal term and a discontinuous term. The nominal term is designed based on the linearized model and optimal control to eliminate any steady-state error, while the discontinuous term is designed based on the sliding surface and the reaching law to force the system state onto the sliding surface under changing disturbances and parameter variations. These two terms are combined to constitute the overall control law. The performance and robustness of the proposed method are assessed through simulation under different uncertainty conditions of the TWMR.