39 documents found, page 1 of 4
Step count algorithm adapted to indoor localization
Terra, Rui; Figueiredo, Lino; Barbosa, Ramiro; Anacleto, RicardoThis paper presents a step count algorithm designed to work in real-time using low computational power. This proposal is our first step for the development of an indoor navigation system, based on Pedestrian Dead Reckoning (PDR). We present two approaches to solve this problem and compare them based in their error on step counting, as well as, the capability of their use in a real time system.
Application of Fractional Calculus in Engineering
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 syst...
Control of a heat diffusion system through a fractional order nonlinear algorithm
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 cont...
Optimization of hexapod locomotion using genetic algorithms
Silva, Manuel; Barbosa, Ramiro; Tenreiro Machado, J. A.Different strategies have been adopted for the optimization of legged robots, either during their design and construction phases, or during their operation. Evolutionary strategies are a way to imitate nature replicating the process that nature designed for the generation and evolution of species. This paper presents a genetic algorithm, running over a simulation application of legged robots, that allows the op...
Some Applications of Fractional Calculus in Engineering
Tenreiro Machado, J. A.; Silva, Manuel; Barbosa, Ramiro; Jesus, Isabel S.; Reis, Cecília; Marcos, Maria G.; Galhano, AlexandraFractional 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 est...
Some applications of fractional calculus in engineering
Tenreiro Machado, J. A.; Silva, Manuel; Barbosa, Ramiro; Jesus, Isabel S.; Reis, Cecília; Marcos, Maria da Graça; Galhano, AlexandraFractional 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 estab...
GA Optimization of an Hexapod Robot Parameters for Periodic Gaits
Silva, Manuel; Barbosa, Ramiro; Tenreiro Machado, J. A.Different strategies have been adopted for the optimization of legged robots, either during their design and construction phases, or during their operation. Evolutionary strategies are a way to "imitate nature" replicating the process that nature designed for the generation and evolution of species. This paper presents a genetic algorithm, running over a simulation application of legged robots, allowing the opt...
Development of a genetic algorithm for the optimization of hexapod robot parame...
Silva, Manuel; Barbosa, Ramiro; Tenreiro Machado, J. A.Legged robots allow the locomotion on terrains inaccessible to other type of vehicles because they do not need a continuous support surface. Different strategies have been adopted for the optimization of these systems, during their design and construction phases, and during their operation. Among the different optimization criteria followed by different authors, it is possible to find issues related to energy e...
Fractional modelling of the electrical conduction in nacl electrolyte
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 anal...
Fractional Order Nonlinear Control of Heat System
Jesus, Isabel S.; Tenreiro Machado, J. A.; Barbosa, RamiroIn the last decade, the interest in the area of fractional calculus and its applications has increased significantly. In this paper, we study a heat diffusion system in a fractional calculus perspective. A fractional order nonlinear controller is proposed, and its tuning, in the viewpoint of several performance indices, is analyzed. The simulations demonstrate the good performance of the proposed fractional-ord...