Robust Synchronisation of Uncertain Fractional-Order Chaotic Unified Systems

Abstract

INTRODUCTIONThe broad field of chaos theory has been among the most interesting issues researchers have studied in recent decades. Concepts related to chaos theory and its related disciplines are employed in different fields, including medicine (Sarbaz et al., 2012;Aghababa and Borjkhani 2014;Provata et al., 2012), economics (Pan et al., 2012;Airaudo and Zanna, 2012), functioning of laser diodes (Banerjee et al., 2012;Gao, 2012), and mathematics (Hosseinalipour, 2013;Kupka, 2014). The control of chaos-related phenomena has attracted wide attention from many different kinds of researchers.Although the idea of fractional-order operators has a history as long as that of integer-order operators, interest in this field is expanding due to an increasing amount of attention from scientists and mathematicians. In recent decades, fractional-order operators have been the driving force behind an increasing number of investigations. With the development of studies in this area, practical and theoretical investigations into the application of fractional-order operators in engineering sciences have now become widespread in the academic community (Padula and Visioli, 2014;Pakzad et al., 2013;Tripathy et al., 2015a;Tripathy et al., 2015b). For example, fractional-order calculations have been applied in mechanical and electrical engineering, biology, economics, and mathematics, among other fields (Hernandez et al., 2014;Wang and Li, 2014;Cortes and Elejabarrieta, 2007).A chaotic system is a highly complex, dynamic nonlinear system. The important and salient characteristics of chaotic systems include their extreme sensitivity to initial conditions, making the synchronisation of chaotic systems vital. The rapid increase in interest in fractional-order chaotic systems has manifested in investigations into the chaotic behavior of fractional-order horizontal platform systems (Aghababa, 2014) and in the proliferation of other published articles on these systems (Yin et al., 2013;Li and Chen, 2014;Li and Tong, 2013).During the past two decades, the control and synchronisation of fractional-order and integer-order chaotic systems have largely attracted scientists and researchers due to their potential applications in secure communications, biological systems, medicine, and other fields. For example, an active-control technique has been provided for the identical and non-identical synchronisation of fractional-order chaotic systems (Srivastava et al., 2014). In a different application, function-projective synchronisations (FPS) of identical and non-identical modified finance systems (MFS) and the Shimizu-Morioka system (S-MS) have been studied via active control technique (Kareem et al., 2012). Fast projective synchronisation of fractional-order chaotic and reverse chaotic systems with its application to an affine cipher using date of birth (DOB) have also been reviewed (Muthukumar PROCEEDINGS OF THE LATVIAN ACADEMY OF SCIENCES. Section B, Vol. 71 (2017)

Fault-tolerant complete synchronization of integer and fractional derivative 6D hyper-chaotic systems with unknown time delay

“…Haris et al (2020) have studied the synchronization of two 3D integer-order chaotic systems without disturbance and uncertainty with unknown parameters using adaptive control. Lin et al (2021) and Noghredani and Balochian (2017) have studied synchronization of a 3D fractional-order chaotic system in the presence of disturbance and known uncertainty using sliding mode control. In Chen et al (2021), two 3D chaotic systems in the absence of disturbance and uncertainty have been synchronized using feedback control.…”