Designing observer based fuzzy terminal sliding mode controller for nonlinear dynamical model of vehicles: fixed time approach

In this paper, an observer based fuzzy fixed time terminal sliding mode controller is proposed for nonlinear dynamic of vehicle model. A novel fixed time terminal sliding mode control structure is proposed to develop the efficiency of the sliding mode controller, where the convergence of tracking error to zero achieves in finite time. A fuzzy logic controller is utilized to tune parameters of the fixed time terminal sliding controller to decrease the chattering phenomena. Variations of vehicle parameters are considered as bounded uncertainties, which are estimated and compensated through the design of developed observer (ESO) controller. Compare to researches that concentrate on robust controller, the proposed method distillates (1) the convergence of the tracking error in finite time (2) the reduction of the chattering by the fuzzy gain (3) designing stable robust observer for the proposed complicated system. Simulation results verify that performance of the suggested methodology to improve in comparison with both the classic PID and sliding mode controller design procedure.