Editorial special issue: “Dynamics and Control of Fractional Order Systems” International Journal of Dynamics and Control

Abstract

Fractional order (FO) differentiation is a generalization of classical integer differentiation to real or complex orders. The origin of this concept dates back to the early days of classical differential calculus, although its inherent complexity postponed its use and application to the engineering world. In the last decades, the developments in computing technologies combined with the unique advantages of FO differ-integrals in modeling complex phenomena, have led to ongoing research interest towards using fractional calculus (FC) as an optimal tool to describe the dynamics of complex systems. Apart from this, FC is currently gaining more and more popularity in the engineering community. Nowadays, the adoption of FC in control engineering has been gaining more and more momentum, both in modeling, identification, and controller design.The aim of this special issue is to promote further development of FC in control engineering, stability analysis of FO systems, solutions for fractional order continuous-time linear systems, signal processing, approximations for fractionalCristina.Pop@aut.utcluj.ro Portugal differ-integrals, modeling various phenomena based on FO differentials and many other topics.The guest editors have carefully reviewed all the submissions, and selected 23 for this special issue. The selected papers are grouped in the three main categories:• FO control strategies: tuning of FO controllers and analysis of closed loop FO systems • Theoretical developments • Other applicationsThe variety of topics addressed reveals the importance of FC in numerous fields and provides an excellent coverage to appeal for each reader's interest.In terms of the control strategies discussed within the special issue, three sliding mode control algorithms are proposed for the synchronization of two identical FO chaotic systems: [1], where the validation of the proposed approach is done through the use of a cryptosystem, defined as a FO chaotic system with minimum effective dimension 2.01; [2], using a Particle Swarm Optimization algorithm is used for optimizing the controller parameters for the synchronization of FO identical and non-identical chaotic and hyper-chaotic systems; [3], where a novel adaptive interval type-2 fuzzy active sliding mode control approach is proposed for synchronization of FO hyper-chaotic systems. In [4] a robust synchronization scheme that incorporates a sliding mode controller established on a new FO surface is proposed. A novel fractional PID controller for commensurate FO systems based on Laguerre orthonormal functions is introduced, in [5] in which the controller parameters are determined by matching the first three coefficients of the Laguerre series of the loop gain with the desired one. The minimization of the integral square error performance index subjected to control signal constraint is used to determine the pole of the FO 123