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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Control of Autonomous Robot Teams in Industrial Applications

Tsalatsanis, Athanasios 27 August 2008 (has links)
The use of teams of coordinated mobile robots in industrial settings such as underground mining, toxic waste cleanup and material storage and handling, is a viable and reliable approach to solving such problems that require or involve automation. In this thesis, abilities a team of mobile robots should demonstrate in order to successfully perform a mission in industrial settings are identified as a set of functional components. These components are related to navigation and obstacle avoidance, localization, task achieving behaviors and mission planning. The thesis focuses on designing and developing functional components applicable to diverse missions involving teams of mobile robots; in detail, the following are presented: 1. A navigation and obstacle avoidance technique to safely navigate the robot in an unknown environment. The technique relies on information retrieved by the robot's vision system and sonar sensors to identify and avoid surrounding obstacles. 2. A localization method based on Kalman filtering and Fuzzy logic to estimate the robot's position. The method uses information derived by multiple robot sensors such as vision system, odometer, laser range finder, GPS and IMU. 3. A target tracking and collision avoidance technique based on information derived by a vision system and a laser range finder. The technique is applicable in scenarios where an intruder is identified in the patrolling area. 4. A limited lookahead control methodology responsible for mission planning. The methodology is based on supervisory control theory and it is responsible for task allocation between the robots of the team. The control methodology considers situations where a robot may fail during operation. The performance of each functional component has been verified through extensive experimentation in indoor and outdoor environments. As a case study, a warehouse patrolling application is considered to demonstrate the effectiveness of the mission planning component.
12

Desenvolvimento de uma arquitetura de controle descentralizada para veículos submarinos baseada em CAN, ARM e Engenharia de Sistemas- CANARMES. / Decentralized control architecture development for underwater vehicles based on CAN, ARM and system engineering - CANARMES.

Luciano Ondir Freire 01 July 2013 (has links)
Os veículos submarinos não tripulados tem uma importância crescente devido à sua flexibilidade e baixo custo. Devido à sua complexidade intrínseca, eles requerem diversas competências diferentes para serem desenvolvidos e permitem realizar pesquisas em vários campos do conhecimento. No contexto de uma universidade, que possui pessoal heterogêneo e de alta rotatividade, faz-se mister adotar uma organização que permita que os esforços de cada aluno possam ser reusados pelos outros, de modo as atividades de pesquisa possam avançar com pouca perda de tempo e retrabalho. Tal necessidade pode ser respondida pela aplicação de conceitos da engenharia de sistemas, tais como modularidade, separação formal entre soluções tecnológicas e necessidades, classificação funcional, critérios para escolha do método de desenvolvimento, uso de referencial normativo técnico, plano tecnológico, integração, verificação e validação e gerenciamento de configurações. Este trabalho se limita a desenvolver uma arquitetura de controle, observando os conceitos de engenharia de sistemas, aplicada a um AUV. É feita uma comparação com outras arquiteturas similares do estado da arte e mostram-se resultados de testes em piscina para esta arquitetura. É mostrado também que foi possível estabelecer a continuidade do desenvolvimento por outros alunos, validando a utilidade da metodologia. Conclui-se que, para aumentar a eficiência da pesquisa universitária, é necessário observar aspectos gerenciais e institucionais além dos aspectos técnicos ao conceber soluções técnicas. / The unmanned underwater vehicles have a growing position due to their flexibility and low cost. Due to their inherent complexity, they require many different skills to be developed and they allow conducting research in various fields of knowledge. In the context of a university, which has heterogeneous staff and high turnover, there is the need of adopting an organization that allows the efforts of each student be reused by others, so research activities can proceed with little loss of time and rework. This need can be answered by the application of system engineering concepts such as modularity, formal separation between technology solutions and needs, functional classification, criteria for the choice of development method, use of technical reference standard, technological plan, integration, verification and validation and configuration management. This work is limited to development of a control architecture, observing the concepts of systems engineering, applied to an AUV. A comparison is made with other similar architectures in the state of the art and shows up test results in the pool for this architecture. It is also shown that it was possible to keep the development by other students, validating the utility of the methodology. It is concluded that in order to increase the efficiency of university research, it must be observed managerial and institutional aspects beyond the technical aspects when designing technical solutions.
13

Arquitetura de controle de movimento para um robô móvel sobre rodas visando otimização energética. / Motion control architecture for a wheeled mobile robot to energy optimization.

Werther Alexandre de Oliveira Serralheiro 05 March 2018 (has links)
Este trabalho apresenta uma arquitetura de controle de movimento entre duas posturas distintas para um robô móvel sob rodas com acionamento diferencial em um ambiente estruturado e livre de obstáculos. O conceito clássico de eficiência foi utilizado para a definição das estratégias de controle: um robô se movimenta de forma eficiente quando realiza a tarefa determinada no menor tempo e utilizando menor quantidade energética. A arquitetura proposta é um recorte do modelo de Controle Hierárquico Aninhado (NHC), composto por três níveis de abstração: (i) Planejamento de Caminho, (ii) Planejamento de Trajetória e (iii) Rastreamento de Trajetória. O Planejamento de Caminho proposto suaviza uma geodésica Dubins - o caminho mais eficiente - por uma Spline Grampeada para que este caminho seja definido por uma curva duplamente diferenciável. Uma transformação do espaço de configuração do robô é realizada. O Planejamento de Trajetória é um problema de otimização convexa na forma de Programação Cônica de Segunda Ordem, cujo objetivo é uma função ponderada entre tempo e energia. Como o tempo de percurso e a energia total consumida pelo robô possui uma relação hiperbólica, um algoritmo de sintonia do coeficiente de ponderação entre estas grandezas é proposta. Por fim, um Rastreador de Trajetória de dupla malha baseado em linearização entrada-saída e controle PID é proposto, e obteve resultados satisfatórios no rastreamento do caminho pelo robô. / This work presents a motion control architecture between two different positions for a differential driven wheeled mobile robot in a obstacles free structured environment. The classic concept of efficiency was used to define the control strategies: a robot moves efficiently when it accomplishes the determined task in the shortest time and using less amount of energy. The proposed architecture is a clipping of the Nested Hierarchical Controller (NHC) model, composed of three levels of abstraction: (i) Path Planning, (ii) Trajectory Planning and (iii) Trajectory Tracking. The proposed Path Planning smoothes a geodesic Dubins - the most efficient path - by a Clamped Spline as this path is defined by a twice differentiable curve. A transformation of the robot configuration space is performed. The Trajectory Planning is a convex optimization problem in the form of Second Order Cone Programming, whose objective is a weighted function between time and energy. As the travel time and the total energy consumed by the robot has a hyperbolic relation, a tuning algorithm to the weighting is proposed. Finnaly, a dual-loop Trajectory Tracker based on input-output feedback linearization and PID control is proposed, which obtained satisfactory results in tracking the path by the robot.
14

Preliminary Implementation of a Modular Control System for Dual-Arm Manipulation with a Humanoid Robot

Verbryke, Matthew R. January 2018 (has links)
No description available.
15

Component-based Intelligent Control Architecture for Reconfigurable Manufacturing Systems

Su, Jiancheng 18 January 2008 (has links)
The present dynamic manufacturing environment has been characterized by a greater variety of products, shorter life-cycles of products and rapid introduction of new technologies, etc. Recently, a new manufacturing paradigm, i.e. Reconfigurable Manufacturing Systems (RMS), has emerged to address such challenging issues. RMSs are able to adapt themselves to new business conditions timely and economically with a modular design of hardware/software system. Although a lot of research has been conducted in areas related to RMS, very few studies on system-level control for RMS have been reported in literature. However, the rigidity of current manufacturing systems is mainly from their monolithic design of control systems. Some new developments in Information Technology (IT) bring new opportunities to overcome the inflexibility that shadowed control systems for years. Component-based software development gains its popularity in 1990's. However, some well-known drawbacks, such as complexity and poor real-time features counteract its advantages in developing reconfigurable control system. New emerging Extensible Markup Language (XML) and Web Services, which are based on non-proprietary format, can eliminate the interoperability problems that traditional software technologies are incompetent to accomplish. Another new development in IT that affects the manufacturing sector is the advent of agent technology. The characteristics of agent-based systems include autonomous, cooperative, extendible nature that can be advantageous in different shop floor activities. This dissertation presents an innovative control architecture, entitled Component-based Intelligent Control Architecture (CICA), designed for system-level control of RMS. Software components and open-standard integration technologies together are able to provide a reconfigurable software structure, whereas agent-based paradigm can add the reconfigurability into the control logic of CICA. Since an agent-based system cannot guarantee the best global performance, agents in the reference architecture are used to be exception handlers. Some widely neglected problems associated with agent-based system such as communication load and local interest conflicts are also studied. The experimental results reveal the advantage of new agent-based decision making system over the existing methodologies. The proposed control system provides the reconfigurability that lacks in current manufacturing control systems. The CICA control architecture is promising to bring the flexibility in manufacturing systems based on experimental tests performed. / Ph. D.
16

Engineering-orientierte Steuerungsarchitektur auf der Basis von Aktionsprimitiven für Anwendungen in der Robotik / Engineering-oriented Control Architecture based on Action Primitives for Applications in Robotics

Hennig, Matthias 16 November 2012 (has links) (PDF)
In der vorliegenden Arbeit wird die flexible Steuerungsarchitektur Apeca für Systeme der Robotik sowie der robotergestützten Fertigungstechnik vorgestellt. Dafür werden verschiedene Anforderungen identifiziert und innerhalb eines Entwurfs vereint. Ein Hauptaugenmerk des dabei entstandenen Konzeptes ist es, einen vereinfachten Engineeringprozess für den Steuerungsentwurf zu ermöglichen. Dieser Ansatz wird durch die Verwendung von Aktionsprimitiven ermöglicht, die in Form atomarer Systemverhalten in einer speziellen Modulhierarchie eingesetzt werden. Hierzu erfolgt innerhalb der Steuerungsarchitektur eine Trennung zwischen einem funktionsorientierten verhaltensbasierten Modell zur hierarchischen sowie funktionell parallelen Ausführung von Aktionsprimitiven und einem ablauforientierten Modell zur aufgabenabhängigen Aktivierung derselben. Mit Hilfe eines Nutzerkonzepts werden diese Modelle verschiedenen Anwendern zugeordnet. Die objektorientierte Realisierung dieses Entwurfs ermöglicht die Verwendung und Synchronisation von mehreren Teilsystemen innerhalb einer Steuerung. In der Arbeit wird sowohl der entstandene Entwurf diskutiert als auch eine prototypische Implementierung vorgestellt. Abschließend werden die Ergebnisse anhand verschiedener Demonstrationsszenarien präsentiert. / In this present work, the Apeca framework, a flexible control architecture for robotic systems, is introduced. The conceptual design combines different requirements identified in miscellaneous robotic control approaches. The main focus of the resulting concept is on a simplified engineering process for the controller design. This approach is supported by the use of atomic system behaviors, the so called action primitives, in a special module hierarchy. For this purpose a distinction between a functional behavior based system model with hierarchically and also parallelly executed action primitives and a sequential control system model with a task-dependent activation of the primitives is proposed. These models are assigned to different users through a distinct user concept. An object-oriented implementation of the proposed architecture allows the utilization and synchronisation of multiple (sub-)systems within one framework. In this work the proposed framework will be discussed, a prototypical implementation will be presented and results based on different experimental scenarios will be shown.
17

Engineering-orientierte Steuerungsarchitektur auf der Basis von Aktionsprimitiven für Anwendungen in der Robotik

Hennig, Matthias 27 August 2012 (has links)
In der vorliegenden Arbeit wird die flexible Steuerungsarchitektur Apeca für Systeme der Robotik sowie der robotergestützten Fertigungstechnik vorgestellt. Dafür werden verschiedene Anforderungen identifiziert und innerhalb eines Entwurfs vereint. Ein Hauptaugenmerk des dabei entstandenen Konzeptes ist es, einen vereinfachten Engineeringprozess für den Steuerungsentwurf zu ermöglichen. Dieser Ansatz wird durch die Verwendung von Aktionsprimitiven ermöglicht, die in Form atomarer Systemverhalten in einer speziellen Modulhierarchie eingesetzt werden. Hierzu erfolgt innerhalb der Steuerungsarchitektur eine Trennung zwischen einem funktionsorientierten verhaltensbasierten Modell zur hierarchischen sowie funktionell parallelen Ausführung von Aktionsprimitiven und einem ablauforientierten Modell zur aufgabenabhängigen Aktivierung derselben. Mit Hilfe eines Nutzerkonzepts werden diese Modelle verschiedenen Anwendern zugeordnet. Die objektorientierte Realisierung dieses Entwurfs ermöglicht die Verwendung und Synchronisation von mehreren Teilsystemen innerhalb einer Steuerung. In der Arbeit wird sowohl der entstandene Entwurf diskutiert als auch eine prototypische Implementierung vorgestellt. Abschließend werden die Ergebnisse anhand verschiedener Demonstrationsszenarien präsentiert. / In this present work, the Apeca framework, a flexible control architecture for robotic systems, is introduced. The conceptual design combines different requirements identified in miscellaneous robotic control approaches. The main focus of the resulting concept is on a simplified engineering process for the controller design. This approach is supported by the use of atomic system behaviors, the so called action primitives, in a special module hierarchy. For this purpose a distinction between a functional behavior based system model with hierarchically and also parallelly executed action primitives and a sequential control system model with a task-dependent activation of the primitives is proposed. These models are assigned to different users through a distinct user concept. An object-oriented implementation of the proposed architecture allows the utilization and synchronisation of multiple (sub-)systems within one framework. In this work the proposed framework will be discussed, a prototypical implementation will be presented and results based on different experimental scenarios will be shown.
18

Proposition d’une architecture holonique auto-organisée et évolutive pour le pilotage des systèmes de production / Self-organized and evolvable holonic architecture for manufacturing control

Barbosa, José 19 February 2015 (has links)
Le monde des entreprises est profondément soumis à un ensemble de contraintes toujours plus exigeantes provenant d’une part des clients, exigeant des produits plus personnalisables, de qualité supérieure et à faible coût, et d’autre part des aléas internes auxentreprises, comprenant les pannes machines, les défaillances humaines, la fluctuation de la demande, les fréquentes variations de production. Cette thèse propose une architecture de contrôle de systèmes de production, basée sur les principes holoniques développées dans l’architecture ADACOR (ADAptive holonic COntrol aRchitecture), et l’étendant en s’inspirant des théories de l’évolution et en utilisant des mécanismes d’auto-organisation. L’utilisation des théories de l’évolution enrichit l’architecture de contrôle en permettant l’évolution de deux manières distinctes, en réponse au type et au degré de la perturbation apparue. Le premier mode d’adaptation, appelé auto-organisation comportementale, permet à chaque entité qui compose le système d’adapter dynamiquement leur comportement interne, gérant de cette façon de petites perturbations. Le second mode, nommé auto-organisation structurelle, traite de plus grandes perturbations, en permettant aux entités du système de ré-organiser leurs relations, et par conséquent modifier structurellement le système. L’architecture holonique auto-organisée de contrôle de systèmes de production proposée dans cette thèse a été validée sur une cellule de production flexible AIP-PRIMECA. Les résultats ont montré une amélioration des indicateurs clés de performance par rapport aux architectures de contrôle hiérarchiques et hétérarchiques. / The manufacturing world is being deeply challenged with a set of ever demanding constraints where from one side, the costumers are requiring products to be more customizable, with higher quality at lower prices, and on other side, companies have to deal on a daily basis with internal disturbances that range from machine breakdown to worker absence and from demand fluctuation to frequent production changes. This dissertation proposes a manufacturing control architecture, following the holonic principles developed in the ADAptive holonic COntrol aRchitecture (ADACOR) and extending it taking inspiration in evolutionary theories and making use of self- organization mechanisms. The use of evolutionary theories enrich the proposed control architecture by allowing evolution in two distinct ways, responding accordingly to the type and degree of the disturbance that appears. The first component, named behavioural self- organization, allows each system’s entity to dynamically adapt its internal behaviour, addressing small disturbances. The second component, named structural self-organization, addresses bigger disturbances by allowing the system entities to re-arrange their rela- tionships, and consequently changing the system in a structural manner. The proposed self-organized holonic manufacturing control architecture was validated at a AIP-PRIMECA flexible manufacturing cell. The achieved experimental results have also shown an improvement of the key performance indicators over the hierarchical and heterarchical control architecture.
19

Implementação de uma arquitetura de controle distribuído para sistema produtivo. / Implementation of a distributed control architecture for productive system.

Fattori, Caio Cesar 20 August 2010 (has links)
Os mercados estão se tornando independentes de barreiras geográficas e as indústrias têm procurado novas configurações de sistemas produtivos (SPs), passando de estruturas centralizadas para estruturas distribuídas, deslocando suas plantas produtivas para países com reservas de energia e baixos custos operacionais. Para permitir a coordenação e gerenciamento deste tipo de SP disperso, aproveita-se dos avanços das tecnologias mecatrônicas e de informação, as quais permitem uma maior cooperação entre as partes do sistema e entre os atores (clientes, operadores, administradores, etc.) envolvidos. Cada parte do SP disperso que também é um SP tem seu grau de autonomia operacional. Esse tipo de sistema apresenta novos problemas de integração e coordenação de componentes, que têm que ser superados para se chegar a uma efetiva implementação. A falta de dados de testes já realizados com estruturas distribuídas dificulta o desenvolvimento prático de SPs dispersos. Este trabalho inicialmente adota uma arquitetura de controle para a negociação entre usuários de um SP disperso. Para a implementação da arquitetura foram desenvolvidos modelos computacionais explorando o potencial da rede de Petri e do PFS (production flow schema) para sistematizar a construção dos modelos. Pela análise dos modelos com base nas propriedades da rede de Petri avaliou-se a arquitetura de controle e estabeleceu-se as especificações que foram adotadas para sua implementação prática. A implementação e os testes foram realizados considerando os subsistemas autônomos de um sistema flexível de montagem que emula um SP disperso. Os estudos, análises e testes realizados foram fundamentais para adquirir maior experiência prática relacionado a concepção, projeto, implementação e operação de arquiteturas de controle distribuído aplicadas a SPs dispersos. / The markets are becoming independent of geographic and industry have sought new configurations of productive systems, from centralized structures to distributed structures, shifting their production plants to countries with energy reserves and low operating costs. To allow the coordination and management of this type of dispersed productive system, takes advantage of advances in mechatronics and information technologies, which allow greater cooperation between parts of the system and among stakeholders (customers, operators, administrators, etc.) involved. Each part of disperse productive system, that is also a productive system, has its own level of operational autonomy. This type of system presents new problems of integration and coordination of components that must be overcome to achieve effective implementation. The lack of data from tests already carried out with distributed structures hinders the practical development of disperse productive systems. This work initially adopts a control architecture for negotiation between users of a disperse productive system. For the implementation of the architecture were developed computational models exploring the potential of Petri networks (PN) and the production flow schema (PFS) to systematize the construction of models. For the analysis of models based on the PN properties we evaluated the control architecture and established the specifications that were used for its practical implementation. The implementation and the tests were performed considering the autonomous subsystems of a flexible mounting system that emulates a disperse productive system. The studies, analysis and tests were essential to acquire more practical experience related to conception, design, implementation and operation of distributed control architectures applied to disperse productive systems.
20

A Learning-based Semi-autonomous Control Architecture for Robotic Exploration in Search and Rescue Environments

Doroodgar, Barzin 07 December 2011 (has links)
Semi-autonomous control schemes can address the limitations of both teleoperation and fully autonomous robotic control of rescue robots in disaster environments by allowing cooperation and task sharing between a human operator and a robot with respect to tasks such as navigation, exploration and victim identification. Herein, a unique hierarchical reinforcement learning (HRL) -based semi-autonomous control architecture is presented for rescue robots operating in unknown and cluttered urban search and rescue (USAR) environments. The aim of the controller is to allow a rescue robot to continuously learn from its own experiences in an environment in order to improve its overall performance in exploration of unknown disaster scenes. A new direction-based exploration technique and a rubble pile categorization technique are integrated into the control architecture for exploration of unknown rubble filled environments. Both simulations and physical experiments in USAR-like environments verify the robustness of the proposed control architecture.

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