Delayed output feedback sliding mode control for uncertain non‐linear systems

Abstract

This study proposes an output feedback sliding mode control with an artificial delay. The output information-based sliding surface is outlined. An artificial delay as well as an exponential decay term is introduced in the sliding surface, which reflects these additional terms (artificial delay and exponential decay term) in the reduced-order dynamics. The idea and advantage of utilising the artificial delay in the sliding surface are to stabilise the class of systems, which are not able to stabilise with only output feedback. The employment of exponential decay term in the sliding surface provides a reaching phase free behaviour. It implies that the authors' approach is insensitive to external matched disturbances from the very initial time. With the aid of Lyapunov–Krasovskii functional, local input to state stability for the reduced-order dynamics as well as for the closed-loop system is presented. Finally, the simulation results of the translation oscillator with rotating actuator system are presented to validate the effectiveness of the offered technique.