Adaptive Sliding-Mode Synchronization of the Memristor-Based Sixth-Order Uncertain Chaotic System and Its Application in Image Encryption

This article presents a memristor-based sixth-order chaotic circuit which is designed based on Chuai (-)s circuit using flux-controlled memristors and charge-controlled memristors. The chaotic characteristics are analyzed, and the chaotic phase diagrams are drawn. The specific upper bound information of the model uncertainty and external disturbance is unknown. We design an adaptive terminal sliding-mode control law for such chaotic systems, which not only compensates the influence of the uncertainty and disturbance but also ensures that the synchronization error system is fixed-time stable when the sliding motion takes place. Also, the accessibility of the sliding surface is guaranteed. Thus, the sufficient conditions for the synchronization of the considered systems are derived. Simulation examples show the significance and superiority of the control scheme. The synchronization strategy is applied to image encryption, and the results show that the encryption effect is excellent and has strong anti-disturbance ability.