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- Realization of fractional-order controllers: analysis, synthesis and application to the velocity control of a servo systemPublication . Barbosa, Ramiro S.; Jesus, Isabel S.; Silva, Manuel F.; Machado, J. A. TenreiroThe synthesis and application of fractional-order controllers is now an active research field. This article investigates the use of fractional-order PID controllers in the velocity control of an experimental modular servo system. The systern consists of a digital servomechanism and open-architecture software environment for real-time control experiments using MATLAB/Simulink. Different tuning methods will be employed, such as heuristics based on the well-known Ziegler Nichols rules, techniques based on Bode’s ideal transfer function and optimization tuning methods. Experimental responses obtained from the application of the several fractional-order controllers are presented and analyzed. The effectiveness and superior performance of the proposed algorithms are also compared with classical integer-order PID controllers.
- Control of a heat diffusion system through a fractional order nonlinear algorithmPublication . Jesus, Isabel S.; Tenreiro Machado, J. A.; Barbosa, RamiroThe application of the FC concepts has increased significantly in different fields of science and engineering, because FC captures properties that classical integer order models neglect. This paper studies a heat diffusion system, that is described through the fractional operator s0.5, under the control of a fractional nonlinear algorithm. The tuning of the algorithm follows the optimization of performance control indices. The results demonstrate the good performance of the proposed controller.
- Application of Fractional Calculus in Control and ElectromagnetismPublication . Tenreiro Machado, J. A.; Barbosa, Ramiro; Jesus, Isabel S.; Silva, Manuel; Reis, Cecília; Figueiredo, LinoThis article illustrates two applications of fractional calculus (FC) in engineering. It has been recognized the advantageous use of this mathematical tool in the modeling and control of many dynamical systems. In this perspective, this paper investigates the use of FC in PID tuning and electrical potential.
- Fractional PID Control of an Experimental Servo SystemPublication . Barbosa, Ramiro; Tenreiro Machado, J. A.; Jesus, Isabel S.This paper investigates the application of fractional-order PID controllers in the velocity control of a servo system. The servo system is controlled by using a real-time digital control system based on MATLAB/Simulink tools. Experimental responses are presented and analyzed, showing the effectiveness of the proposed fractional-order algorithms. Comparison with classical PID controllers is also investigated.
- Applications of fractional calculus in electrical and computer engineeringPublication . Tenreiro Machado, J. A.; Silva, Manuel; Barbosa, Ramiro; Jesus, Isabel S.; Reis, Cecília; Marcos, Maria da Graça; M. Afonso, Luís; Lima, Miguel F. M.; Pires, E. J. Solteiro; Ferreira, N. M. FonsecaFractional Calculus (FC) goes back to the beginning of the theory of differential calculus. Nevertheless, the application of FC just emerged in the last two decades, due to the progress in the area of chaos that revealed subtle relationships with the FC concepts. In the field of dynamical systems theory some work has been carried out but the proposed models and algorithms are still in a preliminary stage of establishment. Having these ideas in mind, the paper discusses a FC perspective in the study of the dynamics and control of several systems. This article illustrates several applications of fractional calculus in science and engineering. It has been recognized the advantageous use of this mathematical tool in the modeling and control of many dynamical systems. In this perspective, this paper investigates the use of FC in the fields of controller tuning, electrical systems, digital circuit synthesis, evolutionary computing, redundant robots, legged robots, robotic manipulators, nonlinear friction and financial modeling.
- Application of Fractional Calculus in EngineeringPublication . Machado, J. A. Tenreiro; Jesus, Isabel S.; Barbosa, Ramiro; Silva, Manuel; Reis, CecíliaFractional Calculus (FC) goes back to the beginning of the theory of differential calculus. Nevertheless, the application of FC just emerged in the last two decades. It has been recognized the advantageous use of this mathematical tool in the modelling and control of many dynamical systems. Having these ideas in mind, this paper discusses a FC perspective in the study of the dynamics and control of several systems. The paper investigates the use of FC in the fields of controller tuning, legged robots, electrical systems and digital circuit synthesis.
- Fractional order dynamical systems and its applicationsPublication . Tenreiro Machado, J. A.; Barbosa, Ramiro; Jesus, Isabel S.; Silva, Manuel; Figueiredo, Lino; Reis, Cecília; Marcos, Maria da Graça; M. Afonso, Luís; Galhano, Alexandra; Duarte, Fernando B.; Lima, Miguel L.; Pires, Eduardo S.; Ferreira, Nuno M. FonsecaThis article illustrates several applications of fractional calculus (FC) in science and engineering. It has been recognized the advantageous use of this mathematical tool in the modeling and control of many dynamical systems. In this perspective, this paper investigates the use of FC in the following fields: Controller tuning; Electrical systems; Traffic systems; Digital circuit synthesis; Evolutionary computing; Redundant robots; Legged robots; Robotic manipulators; Nonlinear friction; Financial modeling.
- Fractional order dynamics in some distributed parameter systemsPublication . Tenreiro Machado, J. A.; Jesus, Isabel S.Fractional Calculus (FC) goes back to the beginning of the theory of differential calculus. Nevertheless, the application of FC just emerged in the last two decades, due to the progress in the area of chaos that revealed subtle relationships with the FC concepts. In the field of dynamical systems theory some work has been carried out but the proposed models and algorithms are still in a preliminary stage of establishment. Having these ideas in mind, the paper discusses a FC perspective in the study of the dynamics and control of some distributed parameter systems.
- Fractional modelling of the electrical conduction in nacl electrolytePublication . Jesus, Isabel S.; Tenreiro Machado, J. A.; Barbosa, RamiroThe fractional calculus (FC) constitutes a mathematical tool that presently is being applied in many emerging scientific areas, such as electricity, magnetism, mechanics, fluid dynamics and medicine. This paper describes the use of an electrolytic process for developing fractional order capacitors. The study includes several experiments for measuring the electrical impedance of the devices. The results are analyzed through the frequency response revealing capacitances of fractional order.
- Towards emerging intelligent transportation systems technologiesPublication . Figueiredo, Lino; Jesus, Isabel S.; Tenreiro Machado, J. A.; Ferreira, José Rui; Carvalho, J. L. Martins deThis paper presents a review of the state of the art on Intelligent Transportation Sytems. ITS involves a large number of research areas and, therefore, this paper focus on those we believe to be the most relevant. The main purpose is to study the achievements attained in the last years and to give an overview of possible directions towards future research.