Combined interval type-2 fuzzy kinematic and dynamic controls of the wheeled mobile robot with adaptive sliding-mode technique

In this paper, an interval type-2 fuzzy kinematic control (IT2-FKC) combined with an interval type-2 adaptive fuzzy sliding-mode dynamic control (IT2-AFSMDC) are proposed for controlling the trajectory-tracking of a nonholonomic wheeled mobile robot (WMR). Firstly, an interval type-2 fuzzy logic controller designed for the kinematic model of the WMR is introduced, and then the IT2-AFSMDC is developed for the dynamic part, which is a combination of the interval type-2 fuzzy logic control (IT2-FLC) and the adaptive fuzzy sliding-mode dynamic control (AFSMDC). Adaption law is introduced to cope with the uncertainties and disturbances of the system. The trajectory-tracking stability is proved by the Lyapunov stability analysis. The validity of the proposed method is demonstrated via computer simulations. The simulation results show that the tracking performance of the IT2-AFSMDC is better than that of the AFSMDC.