A novel nonsingular terminal sliding mode control combined with global sliding surface for uncertain nonlinear second-order systems

This paper proposes a novel nonsingular terminal sliding mode control combined with global sliding surface for a class of uncertain nonlinear second-order systems. The suggested control approach is developed based on the Lyapunov theory. The sliding mode reaching the sliding surface in finite time can be guaranteed. Furthermore, chattering phenomenon caused by the switching control action can be eliminated theoretically, and desirable control performance is realized. The simulation and tank test results for heave control of a remotely operated vehicle are presented to verify the effectiveness of the proposed method.

Robust Sliding Mode Predictive Control of Uncertain Networked Control System with Random Time Delay

This paper proposes a sliding mode predictive controller with a new robust global sliding surface for a certain networked control system with random time delay, mismatched parametric uncertainty, and external disturbances. First, the model of the networked control system is established, based on which linear transformation is made to get a new form of the system which does not have time delay term in expression. Then a global sliding surface is proposed followed by the sufficient condition given in the form of linear matrix inequality (LMI) to guarantee system stability and robustness. Subsequently, a sliding mode predictive controller is proposed with modified reaching law as its reference trajectory and the rolling optimization method is combined to provide optimal control input for each step so that chattering can be minimized. Finally, simulations have been made and the results indicate the advantages of the proposed controller in the aspect of convergence speed, chattering suppression, and robustness to uncertainties.