Robust Tracking Control Of Uncertain Dynamic Nonlinear Systems Via Type-2 Fuzzy Sliding Mode Approach

This paper presents a novel sliding mode control algorithm for an nth order nonlinear system suffering from parameters uncertainty and subjected to external perturbation. Using the proposed approach, the system will be on the sliding surface at the initial time (t=0). The idea is to eliminate the reaching phase and hence, a considerable amelioration of system robustness can be achieved. Moreover, two type-2 fuzzy systems is introduced to construct the indirect adaptive controller. The problems related to adaptive fuzzy controllers like singularity is resolved with the guarantee that all signals of closed-loop system are uniformly ultimately bounded. The proposed controller has many advantages, such as satisfactory control performance under a wide range of operating conditions and parameter variations, a faster response than conventional controller for nonlinear systems and suppressed chattering phenomenon. A simulation example is considered to confirm the efficiency, excellent performance, and robustness of the proposed approach.