Generating Any Number of Initial Offset-Boosted Coexisting Chua's Double-Scroll Attractors via Piecewise-Nonlinear Memristor

Due to the natural nonlinearity and unique memory characteristics, memristors are promising candidates for the construction of multiscroll attractors having better application potential in the field of information encryption than the traditional double-scroll attractors. This article proposes a novel memristive multidouble-scroll Chua's system (MMDSCS) via coupling a nonideal flux-controlled memristor with multipiecewise-linear memductance function in Chua's system directly. Specially, any number of multidouble-scroll chaotic attractors can be generated through adjusting the internal parameters of the memristor conveniently and without changing the original system's nonlinearity. Moreover, the amount of double scrolls is also closely related to the strength of the memristive coupling. Another striking highlight is that infinite initial offset-boosted coexisting Chua's double-scroll attractors with the same shape are produced with the variation of the memristor initial conditions, indicating the emergence of an intriguing phenomenon of homogeneous extreme multistability. This unique property and its formation mechanism are investigated in detail using phase portraits, bifurcation diagrams, Lyapunov exponents, time series, and attraction basins. Furthermore, hardware experiments based on the field-programmable gate array are carried out to confirm the numerical simulations. Finally, an image encryption scheme is designed based on the memristor initial offset boosting dynamics from a perspective of engineering application. In comparison with the existing memristive Chua's systems, the proposed MMDSCS has many merits, such as multidouble-scroll attractors, memristor initial-controlled chaotic sequences with controllability, good robustness, and high security performance, which is more practical in applications involving information confidential communication.

Automated summary

This article proposes a novel memristive multidouble-scroll Chua's system (MMDSCS) that can generate any number of multidouble-scroll chaotic attractors by adjusting the internal parameters of the memristor. The system also exhibits a unique phenomenon of coexisting homogeneous extreme multistability. The formation mechanism of this phenomenon is investigated using various methods, and hardware experiments are carried out to verify the numerical simulations. Furthermore, an image encryption scheme is designed based on the memristor dynamics. The proposed system has advantages such as multidouble-scroll attractors, controllable chaotic sequences, robustness, and high security performance.