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DEVELOPMENT OF A MANUFACTURING CELL IN COMPLIANCE WITH IEC 61499 : Implementation of a function blocks network for controlling a CNC-based systemPalomeque Soto, José Enrique January 2012 (has links)
Today’s market is subjected to numerous changes due to the need of continuous improvement of different commercial brands in order to survive against competitors. This competition drives the evolution of industrial processes, to satisfy the high customers’ requirements. It means that factors such as flexibility, adaptability and agility are crucial for the successful development of industries, which experience some degrees of uncertainty due to machine breakdowns, delays and market fluctuations among others. The current trend in manufacturing industries consists in the implementation of distributed control systems (DCS), substituting the earlier programmable logic controllers (PLC) systems where a main processor operated as the central unit of the system. To this end, the application of function blocks (FB) compliant with the IEC 61499 standard represents an innovative technique for dealing with the design and programming of DCSs. These FBs enable the creation of event-driven networks governed by embedded algorithms that can be used to enhance the flexibility and portability of industrial job-shops based on a distributed architecture. Job-shop floors represent a principal concept in manufacturing industries. This project is focused on the integration of a computer numerically controlled (CNC) machine and a gantry robot which must be coordinated and cooperate for the achievement of an industrial machining and assembly process. It implies the design of a PLC-managed distributed cell using nxtControl software. This software facilitates the construction of FBs-networks to control both machines and enables the communication process via service interface function blocks (SI-FB). Likewise, the whole process will be monitored using an interface also created within nxtControl which will allow the operator to decide the batch and characteristics of the production. This project is also intended to set the basis for the understanding of the FB concept defined in IEC 61499 which moves away from earlier scan-based systems to event-driven models, aiming to contribute to the development of future research in the function blocks area.
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DEVELOPMENT AND EVALUATION OF A CONTROLLER AREA NETWORK BASED AUTONOMOUS VEHICLEDarr, Matthew John 01 January 2004 (has links)
Through the work of researchers and the development of commercially availableproducts, automated guidance has become a viable option for agricultural producers.Some of the limitations of commercially available technologies are that they onlyautomate one function of the agricultural vehicle and that the systems are proprietary toa single machine model.The objective of this project was to evaluate a controller area network (CAN bus)as the basis of an automated guidance system. The prototype system utilized severalmicrocontroller-driven nodes to act as control points along a system wide CAN bus.Messages were transferred to the steering, transmission, and hitch control nodes from atask computer. The task computer utilized global positioning system data to determinethe appropriate control commands.Infield testing demonstrated that each of the control nodes could be controlledsimultaneously over the CAN bus. Results showed that the task computer adequatelyapplied a feedback control model to the system and achieved guidance accuracy levelswell within the range sought. Testing also demonstrated the system's ability tocomplete normal field operations such as headland turning and implement control.
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Λογισμικό για κατανεμημένο έλεγχοΡήγα, Φωτεινή 14 September 2010 (has links)
Η παρούσα εργασία πραγματεύεται ζητήματα που αφορούν σε συστήματα αυτομάτου ελέγχου με ιδιαίτερη έμφαση στα συστήματα κατανεμημένου ελέγχου. Σε αυτό το πλαίσιο, πραγματοποιείται στην εργασία καταρχάς μια σύντομη ανασκόπηση σε σχέση με τα συστήματα ελέγχου και με το πώς αυτά τα συστήματα εισήχθησαν για χρήση στη βιομηχανία. Στη συνέχεια, παρουσιάζονται τα κατανεμημένα συστήματα ελέγχου, τα βασικά χαρακτηριστικά τους αλλά και οι βασικές μεθοδολογίες σχεδίασης ενός τέτοιου συστήματος.
Γίνεται επίσης σημαντική αναφορά στα πολυπρακτορικά συστήματα (Multi Agent Systems – MAS) τα οποία αποτελούν το μέλλον της ανάπτυξης των κατανεμημένων συστημάτων. Τέλος, συνοψίζονται τα βασικά προβλήματα, οι τάσεις αλλά και η κατάσταση στην αγορά αναφορικά με αυτά τα συστήματα. / -
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Modelagem de sistemas de controle distribuídos e colaborativos de sistemas produtivos. / Modeling of distributed collaborative control systems of production systems.Matsusaki, Cristina Toshie Motohashi 27 October 2004 (has links)
O rápido avanço tecnológico nestes últimos anos, principalmente dos recursos computacionais e de comunicação, permite que os sistemas produtivos (SP) evoluam tanto no seu aspecto estrutural quanto no comportamental para que atendam às necessidades crescentes do mercado. Os elementos integrantes dos SP vêm incorporando estes avanços, atingindo maior autonomia e flexibilidade p ara cumprir suas funcionalidades. Além disso, a tendência dos dispositivos de controle de incorporar a capacidade de atuação em ambientes distribuídos onde a interação ocorre através de redes de comunicação, verificada na evolução das normas aplicadas a sistemas de controle, reflete a necessidade de aderência dos sistemas de controle a essa realidade. A necessidade de se manter competitivo no mercado impõe aos atuais SP situações em que emergem novos desafios para realização do controle dos seus processos globais, uma vez que estes assumem múltiplos objetivos, envolvendo diferentes naturezas de indeterminismo, assincronismo e variância no tempo, provocando um nível de complexidade inédito no que se refere ao controle destes sistemas. Este trabalho propõe inicialmente uma nova abstração para modelar-se os SP baseada no conceito de decomposição multidimensional e em múltiplas faces, distribuindo o controle através dos componentes colaborativos. Feito isto, são propostos procedimentos e técnicas para modelagem de sistemas de controle distribuídos e colaborativos (SCDC) de SP. Considera-se para isso, primeiro, uma arquitetura lógica de controle que contemple os múltiplos domínios semânticos presentes em SP, que são provenientes das especificidades dos elementos integrantes. Segundo, a multiplicidade de habilidades necessárias para garantir a execução das estratégias de controle pertinentes a cada domínio. Terceiro, o fluxo de informações heterogêneas provenientes das interações colaborativas entre os domínios. / Recent technological advances, mainly of computer and communication systems, allow the production systems (SP) to evolve in structural aspect as well as in behavioral aspect. The SP resources have achieved enhanced autonomy and flexibility with embedded computer and communication capability. Latest trends of control devices, as seen in the evolution of standards related to control systems, focus on the use of these devices in a distributed environment, where interaction occur through a communication network Thus, the SP control system and its design methods have to fit to this reality. In a competitive scenario, the SP are challenged to keep control of the global processes, considering the multiple goals of these processes and the involvement of different aspect of indeterminism, lack of synchronisms and time variance, generating a inedited complexity level for control of this systems. This work proposes a new abstraction for modeling the control systems of SP, based on the concept of multidimensional decompositions. Based on this, it introduces the procedures and techniques for modeling the distributed and collaborative control systems (SCDC) of the production systems. First, it considers the logic architecture of the control that support many semantic domains presented in this type of SP. Then, the diversity of skills related to each domain necessary to accomplish the control strategies. And then, the heterogeneous information flow through the domains boundaries, derived from the collaborative interaction between the control components.
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Laboratório remoto para ensino a distância de sistemas de controle distribuído / Web laboratory to networked control systems distance learningMossin, Eduardo André 26 February 2007 (has links)
Frente a abrangente presença da internet no ambiente acadêmico e residencial, a literatura relata, na última década, um número crescente de experiências de ensino a distância na área de automação e controle industrial, nas quais desde procedimentos teóricos até aulas práticas podem ser realizados através de acesso remoto. Neste contexto, este trabalho apresenta o estado da arte sobre as experiências acadêmicas no emprego de laboratórios on-line relacionados à teoria de controle e introduz uma nova proposta de arquitetura de acesso remoto, que será aplicada ao ensino de sistemas de controle distribuídos via rede de campo no protocolo FOUNDATION Fieldbus em ambiente simulado. / Due to the increasing presence of the internet in the academic and residential environment, the literature shows an increasing number of experiences of distance learning in the automation and industrial control area in the last decade, in which theoretical procedures as well as practical lessons can be carried out through remote access. In this context, this dissertation presents a brief survey on the academic experiences in the application of on-line laboratories and introduces a new proposal of remote access architecture that will be applied on a distance learning experience in the networked control systems area based on the FOUNDATION Fieldbus protocol using a simulated environment.
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Modelagem de sistemas de controle distribuídos e colaborativos de sistemas produtivos. / Modeling of distributed collaborative control systems of production systems.Cristina Toshie Motohashi Matsusaki 27 October 2004 (has links)
O rápido avanço tecnológico nestes últimos anos, principalmente dos recursos computacionais e de comunicação, permite que os sistemas produtivos (SP) evoluam tanto no seu aspecto estrutural quanto no comportamental para que atendam às necessidades crescentes do mercado. Os elementos integrantes dos SP vêm incorporando estes avanços, atingindo maior autonomia e flexibilidade p ara cumprir suas funcionalidades. Além disso, a tendência dos dispositivos de controle de incorporar a capacidade de atuação em ambientes distribuídos onde a interação ocorre através de redes de comunicação, verificada na evolução das normas aplicadas a sistemas de controle, reflete a necessidade de aderência dos sistemas de controle a essa realidade. A necessidade de se manter competitivo no mercado impõe aos atuais SP situações em que emergem novos desafios para realização do controle dos seus processos globais, uma vez que estes assumem múltiplos objetivos, envolvendo diferentes naturezas de indeterminismo, assincronismo e variância no tempo, provocando um nível de complexidade inédito no que se refere ao controle destes sistemas. Este trabalho propõe inicialmente uma nova abstração para modelar-se os SP baseada no conceito de decomposição multidimensional e em múltiplas faces, distribuindo o controle através dos componentes colaborativos. Feito isto, são propostos procedimentos e técnicas para modelagem de sistemas de controle distribuídos e colaborativos (SCDC) de SP. Considera-se para isso, primeiro, uma arquitetura lógica de controle que contemple os múltiplos domínios semânticos presentes em SP, que são provenientes das especificidades dos elementos integrantes. Segundo, a multiplicidade de habilidades necessárias para garantir a execução das estratégias de controle pertinentes a cada domínio. Terceiro, o fluxo de informações heterogêneas provenientes das interações colaborativas entre os domínios. / Recent technological advances, mainly of computer and communication systems, allow the production systems (SP) to evolve in structural aspect as well as in behavioral aspect. The SP resources have achieved enhanced autonomy and flexibility with embedded computer and communication capability. Latest trends of control devices, as seen in the evolution of standards related to control systems, focus on the use of these devices in a distributed environment, where interaction occur through a communication network Thus, the SP control system and its design methods have to fit to this reality. In a competitive scenario, the SP are challenged to keep control of the global processes, considering the multiple goals of these processes and the involvement of different aspect of indeterminism, lack of synchronisms and time variance, generating a inedited complexity level for control of this systems. This work proposes a new abstraction for modeling the control systems of SP, based on the concept of multidimensional decompositions. Based on this, it introduces the procedures and techniques for modeling the distributed and collaborative control systems (SCDC) of the production systems. First, it considers the logic architecture of the control that support many semantic domains presented in this type of SP. Then, the diversity of skills related to each domain necessary to accomplish the control strategies. And then, the heterogeneous information flow through the domains boundaries, derived from the collaborative interaction between the control components.
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Laboratório remoto para ensino a distância de sistemas de controle distribuído / Web laboratory to networked control systems distance learningEduardo André Mossin 26 February 2007 (has links)
Frente a abrangente presença da internet no ambiente acadêmico e residencial, a literatura relata, na última década, um número crescente de experiências de ensino a distância na área de automação e controle industrial, nas quais desde procedimentos teóricos até aulas práticas podem ser realizados através de acesso remoto. Neste contexto, este trabalho apresenta o estado da arte sobre as experiências acadêmicas no emprego de laboratórios on-line relacionados à teoria de controle e introduz uma nova proposta de arquitetura de acesso remoto, que será aplicada ao ensino de sistemas de controle distribuídos via rede de campo no protocolo FOUNDATION Fieldbus em ambiente simulado. / Due to the increasing presence of the internet in the academic and residential environment, the literature shows an increasing number of experiences of distance learning in the automation and industrial control area in the last decade, in which theoretical procedures as well as practical lessons can be carried out through remote access. In this context, this dissertation presents a brief survey on the academic experiences in the application of on-line laboratories and introduces a new proposal of remote access architecture that will be applied on a distance learning experience in the networked control systems area based on the FOUNDATION Fieldbus protocol using a simulated environment.
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EFFICIENT RESOURCE ALLOCATION IN NETWORKS: FROM CENTRALIZED TO DISTRIBUTED APPROACHESCiyuan Zhang (17409372) 21 November 2023 (has links)
<p dir="ltr">Network models are essential for representing a myriad of real-world problems. Two of the most important categories of networks are centralized and distributed networks. In this thesis, we investigate the efficient resource allocation for one centralized communication network and two distributed epidemic networks.</p><p dir="ltr">In Chapter 2, we study three proposed centralized coded caching schemes with uncoded pre-fetching for scenarios where end users are grouped into classes with different file demand sets. We provide a lower bound for the transmission rate for the system with heterogeneous user profiles. Then the transmission rates of the three schemes are compared with the lower bound to evaluate their gap to optimality, and also compared with each other to show that each scheme can outperform the other two when certain conditions are met. Finally, we propose a cache distribution method that results in a minimal peak rate and a minimal average rate for one of the schemes when the users’ storage is relatively small compared with the size of the library.</p><p dir="ltr">In Chapter 3, we examine a discrete-time networked SIR (susceptible-infected-recovered) epidemic model, where the infection, graph, and recovery parameters may be time-varying. We propose a stochastic framework to estimate the system states from observed testing data and provide an analytic expression for the error of the estimation algorithm. We validate some of our assumptions for the stochastic framework with real COVID-19 testing data. We identify the system parameters with the system states from our estimation algorithm. Employing the estimated system states, we provide a novel distributed eradication strategy that guarantees at least exponential convergence to the set of healthy states. We illustrate the results via simulations over northern Indiana, USA.</p><p dir="ltr">In Chapter 4, we propose a novel discrete-time multi-virus SIR model that captures the spread of competing SIR epidemics over a population network. First, we provide a sufficient condition for the infection level of all the viruses over the networked model to converge to zero in exponential time. Second, we propose an observation model which captures the summation of all the viruses’ infection levels in each node, which represents the individuals who are infected by different viruses but share similar symptoms. We present a sufficient condition for the model to be strongly locally observable. We propose a distributed Luenberger observer for the system state estimation. We demonstrate how to calculate the observer gain for the estimator and prove that the estimation error of our proposed estimator converges to zero asymptotically with the observer gain found. We also propose a distributed feedback controller which guarantees that all viruses are eradicated at an exponential rate. We then show via simulations that the estimation error of the Luenberger observer converges to zero before the viruses die out.</p><p dir="ltr">We conclude in Chapter 5, where we summarize the findings of this thesis and introduce several challenging open research questions that arise from its results. These questions encompass a range of topics, including the design of optimal testing strategies for large populations, the investigation of estimation techniques in the presence of noisy measurement models, the extension of the SIR epidemic model to more complex models like SEIR and SAIR, and the exploration of efficient vaccine allocation schemes.</p>
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Applied Real-Time Integrated Distributed Control Systems: An Industrial Overview and an Implemented Laboratory Case StudyZaitouni, Wael K 08 1900 (has links)
This thesis dissertation mainly compares and investigates laboratory study of different implementation methodologies of applied control systems and how they can be adopted in industrial, as well as commercial, automation applications. Namely the research paper aims to assess or evaluate eventual feedback control loops' performance and robustness over multiple conventional or state-of-the-art technologies in the field of applied industrial automation and instrumentation by implementing a laboratory case study setup: the ball on beam system. Hence, the paper tries to close the gap between industry and academia by: first, conducting a historical study and background information of main evolutional and technological eras in the field of industrial process control automation and instrumentation. Then, some related basic theoretical as well as practical concepts are reviewed in Chapter 2 of the report before displaying the detailed design. After that, the next Chapter, analyses the ball on beam control system problem as the case studied in the context of this research through reviewing previous literature, modeling and simulation. The following Chapter details the proposed design and implementation of the ball on beam case study as if it is under the introduced distributed industrial automation architecture. Finally, Chapter 5 concludes this work by listing several points leaned, remarks, and observations, and stating possible development and the future vision of this research.
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Contribution à l'évaluation de la sûreté de fonctionnement des Systèmes Instrumentés de Sécurité à Intelligence Distribuée / Contribution to assessing the dependability of safety instrumented systems integrating intelligenceMkhida, Abdelhak 14 November 2008 (has links)
L’incorporation des instruments intelligents dans les boucles de sécurité nous mène vers une sécurité intelligente et les systèmes deviennent des « systèmes instrumentés de sécurité à intelligence distribuée (SISID) ». La justification de l’usage de ces instruments dans les applications de sécurité n’est pas complètement avérée. L’évaluation de la sûreté de fonctionnement de ce type de systèmes n’est pas triviale. Dans ce travail, la modélisation et l'évaluation des performances relatives à la sûreté de fonctionnement des systèmes instrumentés de sécurité (SIS) sont traitées pour des structures intégrant de l’intelligence dans les instruments de terrain. La méthodologie que nous utilisons consiste en la modélisation de l’aspect fonctionnel et dysfonctionnel de ces systèmes en adoptant le formalisme basé sur les réseaux de Petri stochastiques qui assurent la représentation du comportement dynamique de ce type de systèmes. La modélisation est traitée sous la forme d’une approche stochastique utilisant les réseaux d’activité stochastiques SAN (Stochastic Activity Network). L’introduction d’indicateurs de performances permet de mettre en évidence l’effet de l’intégration des niveaux d’intelligence dans les applications de sécurité. La méthode de Monte Carlo est utilisée pour évaluer les paramètres de sûreté de fonctionnement des SIS en conformité avec les normes de sécurité relatives aux systèmes instrumentés de sécurité (CEI 61508 et CEI 61511). Nous avons proposé une méthode et les outils associés pour approcher cette évaluation par simulation et ainsi apporter une aide à la conception des systèmes instrumentés de sécurité (SIS) intégrant quelques fonctionnalités des instruments intelligents / The incorporation of intelligent instruments in safety loops leads towards the concept of intelligent safety and the systems become “Intelligent Distributed Safety Instrumented Systems (IDSIS)”. The justification for using these instruments in safety applications is not fully proven and the dependability evaluation of such systems is a difficult task. Achieved work in this thesis deals with modelling and thus the performance evaluation relating to the dependability for structures which have intelligence in the instruments constituting the Safety Instrumented Systems (SIS). In the modelling of the system, the functional and dysfunctional aspects coexist and the dynamic approach using the Stochastic Activity Network (SAN) is proposed to overcome the difficulties mentioned above. The introduction of performance indicators highlight the effect of the integration of intelligence levels in safety applications. Monte-Carlo method is used to assess the dependability parameters in compliance with safety standards related to SIS (IEC 61508 & IEC 61511). We have proposed a method and associated tools to approach this evaluation by simulation and thus provide assistance in designing Safety Instrumented Systems (SIS) integrating some features of intelligent tools
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