Percorrer por autor "Couceiro, Micael S."
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- Analysis and control of a dragonfly-inspired robotPublication . Couceiro, Micael S.; Ferreira, N. M. Fonseca; Tenreiro Machado, J. A.Dragonflies demonstrate unique and superior flight performances than most of the other insect species and birds. They are equipped with two pairs of independently controlled wings granting an unmatchable flying performance and robustness. In this paper it is studied the dynamics of a dragonfly-inspired robot. The system performance is analyzed in terms of time response and robustness. The development of computational simulation based on the dynamics of the robotic dragonfly allows the test of different control algorithms. We study different movement, the dynamics and the level of dexterity in wing motion of the dragonfly. The results are positive for the construction of flying platforms that effectively mimic the kinematics and dynamics of dragonflies and potentially exhibit superior flight performance than existing flying platforms.
- Biological inspired flying robotPublication . Couceiro, Micael S.; Ferreira, N. M. Fonseca; Figueiredo, Carlos M.; Tenreiro Machado, J. A.This paper presents the development of computational simulation based on the dynamics of a robotic bird. The study analyze the wing angle of attack and the velocity of the bird, the tail influence, the gliding flight and the flapping flight with different strategies and algorithms of control. The results are positive for the construction of flying robots. Some highlights are given about the fist implemented architecture of the structure of a robotic bird. This platform consists on a body, wings and tail with actuators independently controlled though a microcontroller; a radio transmission system and batteries are used in order to avoid wired connections between the computer and the robot.
- Cooperative Transportation of an Object based on Fractional Order ControllersPublication . Figueiredo, Carlos M.; Couceiro, Micael S.; Ferreira, N. M. Fonseca; Tenreiro Machado, J. A.Advanced control techniques have been used in simulations to overcome nonlinear phenomena in order to describe the performance of robots with two rotational (RR) degrees-of-freedom (dof). Given the current state-of-the-art, fractional order algorithms lead to better performance when compared to integer order controllers. Also, the development of simulation platforms allows evaluating the best control methodology. In this context, the use of RR robots attached to mobile platforms, denoted in this paper as RR mobile robots, demonstrates a remarkable ability in manipulating and transporting objects. The present work aims to study two cooperative RR mobile robots by analyzing the manipulator’s trajectory and the forces applied to the common load. Are considered two robotic platforms based on an 8-bit microcontroller with inverse kinematics based on the Denavit-Hartenberg formulation and fractional order PID controllers inspired in the Grünwald-Letnikov definition.
- Dynamical Stability and Predictability of Football Players: The Study of One MatchPublication . Couceiro, Micael S.; Clemente, Filipe M.; Martins, Fernando M. L.; Machado, J. A. TenreiroThe game of football demands new computational approaches to measure individual and collective performance. Understanding the phenomena involved in the game may foster the identification of strengths and weaknesses, not only of each player, but also of the whole team. The development of assertive quantitative methodologies constitutes a key element in sports training. In football, the predictability and stability inherent in the motion of a given player may be seen as one of the most important concepts to fully characterise the variability of the whole team. This paper characterises the predictability and stability levels of players during an official football match. A Fractional Calculus (FC) approach to define a player’s trajectory. By applying FC, one can benefit from newly considered modeling perspectives, such as the fractional coefficient, to estimate a player’s predictability and stability. This paper also formulates the concept of attraction domain, related to the tactical region of each player, inspired by stability theory principles. To compare the variability inherent in the player’s process variables (e.g., distance covered) and to assess his predictability and stability, entropy measures are considered. Experimental results suggest that the most predictable player is the goalkeeper while, conversely, the most unpredictable players are the midfielders. We also conclude that, despite his predictability, the goalkeeper is the most unstable player, while lateral defenders are the most stable during the match.
- Electric vehicle drive system with adaptive PID controlPublication . Couceiro, Micael S.; Figueiredo, Carlos M.; Lebres, C.; Ferreira, N. M. Fonseca; Tenreiro Machado, J. A.The aim of this work is to implement an adaptive PID SISO feedback control to obtain a fine adjustment of an electric vehicle (EV) driving system. Our research work is done under different operating conditions, namely, variable battery voltage and variable load. A comparison between conventional and adaptive PID algorithms is established when they are applied to the above mentioned conditions. Experimental results indicate that the adaptive PID controller leads to a faster response and a better stability. Furthermore, the adaptive PID controller follows a given reference velocity faster and more smoothly than the conventional PID controller.
- Fractional Order Darwinian Particle Swarm OptimizationPublication . Couceiro, Micael S.; Ferreira, N. M. Fonseca; Tenreiro Machado, J. A.The Darwinian Particle Swarm Optimization (DPSO) is an evolutionary algorithm that extends the Particle Swarm Optimization (PSO) using natural selection, or survival-of-the-fittest, to enhance the ability to escape from local optima. This paper presents a method for controlling the convergence rate of the DPSO using fractional calculus (FC) concepts. The fractional order (FO) DPSO, denoted as FO-DPSO, is tested using several well-known functions and the relationship between the fractional order velocity and the convergence of the algorithm is observed.
- Fractional-order control of a robotic birdPublication . Couceiro, Micael S.; Ferreira, N. M. Fonseca; Tenreiro Machado, J. A.In this paper it is studied the relation between the angle of attack and the velocity of the bird, the tail influence over the bird trajectory, the gliding and the flapping flight in a closed loop with fractional order controllers. The results are positive for the design and construction of flying robots having similarities with flying animals. The development of computational simulation based on the dynamic of the robotic bird that should allow testing strategies and algorithms of control.
- Fractional-order control of cooperative robotsPublication . Figueiredo, C. M.; Couceiro, Micael S.; Ferreira, N. M. Fonseca; Tenreiro Machado, J. A.In this paper it is studied the implementation of fractional-order algorithms in the position/force control of two cooperating robotic manipulators. The system performance is analyzed in the time and frequency domains. We analyze and compare different control methodologies such as the integer and the fractional-order PID presenting the simulation results assessing the performance of the proposed fractional-order algorithms.
- A fuzzified systematic adjustment of the robotic Darwinian PSOPublication . Couceiro, Micael S.; Machado, J. A. Tenreiro; Rocha, Rui P.; Ferreira, Nuno M. F.The Darwinian Particle Swarm Optimization (DPSO) is an evolutionary algorithm that extends the Particle Swarm Optimization using natural selection to enhance the ability to escape from sub-optimal solutions. An extension of the DPSO to multi-robot applications has been recently proposed and denoted as Robotic Darwinian PSO (RDPSO), benefiting from the dynamical partitioning of the whole population of robots, hence decreasing the amount of required information exchange among robots. This paper further extends the previously proposed algorithm adapting the behavior of robots based on a set of context-based evaluation metrics. Those metrics are then used as inputs of a fuzzy system so as to systematically adjust the RDPSO parameters (i.e., outputs of the fuzzy system), thus improving its convergence rate, susceptibility to obstacles and communication constraints. The adapted RDPSO is evaluated in groups of physical robots, being further explored using larger populations of simulated mobile robots within a larger scenario.
- Hybrid adaptive control of a dragonfly modelPublication . Couceiro, Micael S.; Ferreira, Nuno M. F.; Machado, J. A. TenreiroDragonflies show unique and superior flight performances than most of other insect species and birds. They are equipped with two pairs of independently controlled wings granting an unmatchable flying performance and robustness. In this paper, it is presented an adaptive scheme controlling a nonlinear model inspired in a dragonfly-like robot. It is proposed a hybrid adaptive (HA) law for adjusting the parameters analyzing the tracking error. At the current stage of the project it is considered essential the development of computational simulation models based in the dynamics to test whether strategies or algorithms of control, parts of the system (such as different wing configurations, tail) as well as the complete system. The performance analysis proves the superiority of the HA law over the direct adaptive (DA) method in terms of faster and improved tracking and parameter convergence.