Design of sliding mode control with state varying gains for a Benchmark Twin Rotor MIMO System in Horizontal Motion

Abstract

In this paper, a sliding mode control (SMC) with state-varying gains is proposed to control the yaw orientation of the Twin Rotor MIMO System (TRMS). This proposed SMC algorithm reduces the chattering effect without affecting the properties of the robustness of the sliding modes. The salient feature of this control is that the magnitude of the variable gains depends on the absolute values of the states and tracking error. This design exhibits a relation between first-order and higher-order sliding mode control algorithms. Besides, the developed control strategy does not overestimate disturbances. Hence, the energy utilized by the control effort is reduced significantly. The stability analysis is accomplished by considering the TRMS model in the horizontal plane to illustrate the asymptotic stability condition. Further, a comparison between the twisting algorithm and the proposed control law is highlighted. However, it is evinced that the proposed variable gain SMC is a combination of a twisting algorithm and conventional SMC. Simulations studies are carried out to highlight the efficacies of the proposed controller using MATLAB/Simulink environment.