DSpace Angular :: Browsing CRIIS - Book Chapters by Issue Date

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Environmental Impact Assessment and Management of Sewage Outfall Discharges Using AUV'S

( 2009) Mário Neves ; Patrícia Ramos

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Fault Tolerant Depth Control of the MARES AUV

( 2011) Bruno Miguel Ferreira ; Aníbal Matos ; Nuno Cruz

Control theory has been applied to several domains where practical considerations are relevant. Robotics is a notable example of this. In most cases, mobile robotic systems are governed such that their behavior obeys to a defined motion. However, during their operations, it is conceivable that faults could occur. Indeed, this assumption has to be made in order to predict a possible malfunction and to take an appropriate action according to the fault, improving the robustness and the reliability of the system. This work tackles the problem of fault detection, identification and automatic reconfiguration of an autonomous underwater vehicle (AUV). Although our emphasis will be directed to an AUV, the methods and the tools that are employed in this chapter can be easily extended to other engineering problems beyond robotics.

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Mapping and dilution estimation of wastewater discharges based on geostatistics using an Autonomous Underwater Vehicle

( 2011) Patrícia Ramos ; Nuno Miguel Abreu

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Meta-heuristics Self-Parameterization in a Multi-Agent Scheduling System Using Case-Based Reasoning

( 2012) Paulo Moura Oliveira ; Ivo Pereira ; Ana Madureira

This paper proposes a novel agent-based approach to Meta-Heuristics self-configuration. Meta-heuristics are algorithms with parameters which need to be set up as efficient as possible in order to unsure its performance. A learning module for self-parameterization of Meta-heuristics (MH) in a Multi-Agent System (MAS) for resolution of scheduling problems is proposed in this work. The learning module is based on Case-based Reasoning (CBR) and two different integration approaches are proposed. A computational study is made for comparing the two CBR integration perspectives. Finally, some conclusions are reached and future work outlined

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Tracking Players in Indoor Sports Using a Vision System Inspired in Fuzzy and Parallel Processing

( 2012) Catarina Brito Santiago ; Luís Paulo Reis ; José Lobinho Gomes ; Armando Sousa

Sports are an important part of nowadays society and there is an increasing interest by the sports' community on having mechanisms that allow them to better understand the dynamics of teams (their own and their opponents). This information is frequently extracted manually by operators that, after the game, visualize game recordings (frequently TV footages) and perform hand annotation, which is a time consuming and error prone task. There is a clear necessity for developing automatic mechanisms and methodologies which allow performing these tasks much faster and systematically. The importance of such systems was first highlighted in the late 80's by Franks et al. ( (Franks & Nagelkerke, 1988; Franks et al., 1987) ). In this chapter, we present an automatic and intelligent visual system for detecting and tracking handball players based on two cameras that cover the entire playing area. The followed methodology includes the identification of foreground pixels using dynamic background subtraction, the definition of colour subspaces for each team using a Fuzzy inspired model that allows detecting the players based on the colour properties of their clothes. Player tracking is further improved by using one Kalman Filter per player (object to track). The resulting information is aggregated in an undistorted image view of the entire field that is very interesting and meaningful to the target end-user. The generation of the video is a demanding computational task that t

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Development of an AGV controlled by fuzzy logic

( 2013) Barbosa,RS ; Manuel Santos Silva ; Osório,DJ ; 5655

This paper presents the development of a behavior-based AGV using fuzzy logic. A robot platform and a fuzzy logic controller (FLC) are developed for the embodiment of different behaviors. Experimental results are given to assess the performance of the AGV and to validate the proposed design schemes for its construction and control. © 2013, Springer Science Business Media Dordrecht.

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Magnetic wheeled climbing robot: Design and implementation

( 2013) Manuel Santos Silva ; Barbosa,RS ; Oliveira,ALC ; 5655

This paper presents a climbing robot, with wheeled locomotion and adhesion through permanent magnets. This machine was developed to be used in the inspection of several types of man-made ferromagnetic structures, such as towers for wind turbines, fuel storage tanks, ship hulls, etc., in order to, for instance, detect weaknesses due to corrosion. In this article are presented the main aspects taken into consideration for its design, as well as several constructive aspects, among which are detailed its mechanical and electrical construction, the implemented control architecture and the Human-Machine Interface (HMI) for its control. The distinguishing characteristic of this robot is its dynamic adjustment system of the permanent magnets to assure the machine adhesion to the surfaces when crossing slightly irregular and curved surfaces with a large radius. © 2013, Springer Science Business Media Dordrecht.

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Fractional particle swarm optimization

( 2014) Eduardo Pires ; Machado,JAT ; Paulo Moura Oliveira

The paper addresses new perspective of the PSO including a fractional block. The local gain is replaced by one of fractional order considering several previous positions of the PSO particles. The algorithm is evaluated for several well known test functions and the relationship between the fractional order and the convergence of the algorithm is observed. The fractional order influences directly the algorithm convergencerate demonstrating a large potential for developments. © Springer Science+Business Media Dordrecht 2014.

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Optimization of quadruped robot locomotion gaits through a genetic algorithm

( 2014) Manuel Santos Silva

During the last years research and development on legged robots has grown steadily. Leggedsystems present major advantages when compared with “traditional” vehicles, allowinglocomotion in terrain inaccessible to vehicles with wheels and tracks. However, its energy consumption still lag being these vehicles, existing several aspects that need to be improvedand optimized.One of them regards the parameters values that these machines should adopt to minimize the energy consumption. Due to the large number of parameters involved in this optimization process one way to achieve meaningful results is using evolutionary strategies. Genetic Algorithms are away to “imitate nature”replicating the process that nature designed forthe generation and evolutionof species. The objective of this paper is to present a genetic algorithm, running over a simulationapplication oflegged robots, which allows the optimization of several parameters of a quadrupedrobot model, for distinct locomotion gaits. © Springer Science+Business Media Dordrecht 2014.

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Towards Active Course Marks for Autonomous Sailing Competitions