Robust output feedback control for uncertain chaotic systems

Chaos phenomena can be found in many scientific disciplines such as astronomy, biology, chemistry, engineering, geology, mathematics, medicine, meteorology, and even social sciences. Such phenomena can seriously affect the behaviour of some vital applications such as communications and security systems. Hence, a controller is required to handle chaotic behaviours that affect systems stability. In this paper, a robust output feedback controller is proposed to stabilise electronic circuits used in communications and security systems that exhibit chaotic behaviours. The proposed controller is designed to deal with unknown system parameters and time-varying uncertainties. Only the system output is utilised in the proposed controller while estimating the system states. For that purpose, a high gain observer is designed and utilised to estimate the unknown states. In addition, a numerical study is introduced to demonstrate the robustness and effectiveness of the controller design under various system configurations and different operating conditions. As a result, a satisfactory tracking performance is observed.