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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.
51

Order Driven Flexible Shop Management

Bulut, Aykut 01 July 2011 (has links) (PDF)
The difficulties in responding to variation in product order mixes and load levels effectively in make to order are known. Most of the existing approaches consider releasing jobs to the shop (input control), changing capacity levels (output control) in a controlled way, order acceptance with different definitions of work load and due date assignment. Controlling the processes, routing options and the order accepting capacity with various tool combinations that will decrease tool loading are not considered properly. However the manufacturing flexibility provided by the computer numerically controlled (CNC) machines, provides both part variety and due date achievement given a reasonable extra capacity. Positive effects of flexibility on the due date achievement of the make to order is shown with a variety of experimental and field studies leaving little doubt. However taking flexibility only as a strategic issue and not considering it as a means of planning and management in either the short term or medium term decisions have been commonplace practice. In this study, benefits of providing three kinds of flexibility, considering order pool and acceptance probability of the new arrivals in a periodic setting, is the focal issue. If the required flexible environment is provided, the necessity to make a detailed job loading, route planning and scheduling will be reduced to a low level and a high shop congestion and due date achievement will be realized simultaneously. A typical realistic shop with a scaled part mix is assumed in the flexibility management modeling and simulation experiments are conducted applying periodical flexibility planning approach. These experiments briefly support the ideas that worth of anticipation is more than plain expectations and flexibility improves robustness.
52

Supervisor Synthesis for Automated Manufacturing Systems Based on Structure Theory of Petri Nets. / Synthèse de contrôleurs de Systèmes de production automatisés basés sur la théorie structurelle des réseaux de Petri.

Liu, Gaiyun 27 December 2014 (has links)
Le contrôle de systèmes industriels à cause de l’automatisation et la réduction de nombre des opérateurs devient un enjeu crucial. Les systèmes de production automatisés (AMS) sont d’autant plus touchés car une défaillance du programme de contrôle peut réduire considérablement la productivité voire entraîner l’arrêt du système de production. Pour certains de ces systèmes où le partage des ressources est pondérant, la notion de blocage partiel ou global est fréquente et la validation avant implantation est préférable pour réduire les risques.En raison de la capacité des réseaux de Petri à décrire aisément l’exécution concurrente des processus et le partage des ressources, de nombreuses méthodes de vérification d’absence de blocage et de synthèse de contrôleurs basées sur la théorie structurelle ou le graphe d’accessibilité des réseaux de Petri ont été proposées au cours des deux dernières décennies.Traditionnellement, une méthode de prévention de blocage est évaluée selon trois critères de performance: la complexité structurelle, la permissivité comportementale, et la complexité de calcul. Les méthodes fondées sur l’espace d’état aboutissent généralement à un contrôle maximal permissif mais souffrent de l'explosion combinatoire de l'espace d'états. En revanche, les méthodes de synthèse de contrôleurs fondées sur l’analyse structurelle évitent le problème de l’explosion de l’espace d’état mais aboutissent à des superviseurs pouvant restreindre considérablement les comportements admissibles du système. De plus si la théorie structurelle de contrôle de siphons pour la synthèse des superviseurs est mature dans le cas des réseaux de Petri ordinaires, elle est en développement pour les réseaux de Petri généralises. Par ailleurs, la plupart des travaux existants partent du principe que les ressources sont constamment disponibles. Or l’indisponibilité de ressources est en réalité un phénomène ordinaire. Il serait donc judicieux de développer une politique de vérification de blocage qui soit efficace tout en considérant des ressources non fiables.Cette thèse vise principalement à faire face aux limitations mentionnées ci-dessus. Nos principales contributions à la fois théoriques et algorithmiques sont les suivantes.Premièrement, après avoir revisité les conditions de contrôlabilité des siphons (cs–propriété) et précisé les limitations de la max cs- propriété et max’ cs- propriété, nous définissons la max’’ cs-propriété et nous démontrons que cette nouvelle propriété est une condition non seulement suffisante mais aussi nécessaire pour la vivacité de la classe des GS3PR (Generalized Systems of SimpleSequential Processes with Resources).Par la suite nous montrons comment le problème de la vérification de cette propriété et donc la vivacité des GS3PR peut se ramener à la résolution d’un programme linéaire en nombre entiers.Dans une seconde partie, nous proposons une classe de réseaux de Petri appelée M-Nets dotée d’une forte capacité de modélisation des systèmes de production automatisés. En combinant la théorie du contrôle siphon avec la théorie des régions, nous développons une méthode de prévention de blocage ayant un bon compromis entre l'optimalité du comportement et la complexité de calcul. De plus, nous proposons une méthode de synthèse d'un contrôleur maximal permissif pour une sous-classe de réseaux notée b-nets.Enfin, nous proposons dans cette thèse une méthode de conception d’un superviseur de systèmes de production automatisés où les ressources ne sont pas toutes fiables et particulièrement efficace pour la classe des S3PR (Systems of Simple Sequential Processes with Resources). / Because of automation and reduction of the number of operators, the control of industrial systems is becoming a critical issue. For automated manufacturing systems (AMS) where resource sharing is preponderant, the notion of partial or total blocking is frequent and validation before implementation is preferable to reduce the risks.Due to the easy and concise description of the concurrent execution of processes and the resource sharing by Petri nets, many methods to verify deadlock-freeness and to synthesize controllers using structural theory or reachability graph have been proposed over the past two decades.Traditionally, a deadlock control policy can be evaluated by three performance criteria : structural complexity, behavioral permissiveness, and computational complexity. Generally, deadlock control policies based on the state space analysis can approach the maximal permissive behavior, but suffer from the state explosionproblem. On the contrary deadlock control policies based on the structural analysis of Petri nets avoid in general the state explosion problem successfully, but cannot lead to the maximally or near maximally permissive controller. Morover, the current Deadlock control theory based on siphons is fairly mature for ordinary Petri nets,while for generalized Petri nets, it is presently at an early stage.On the other hand, most deadlock control policies based on Petri nets for AMS proceed on the premise that the resources in a system under consideration are reliable. Actually, resource failures are inevitable and common in most AMS, which may also cause processes to halt. Therefore, it is judicious to develop an effective and robust deadlock control policy considering unreliable resources.This thesis aims to cope with the limitations mentioned above. Our main theoretical and algorithmic contributions are the following. Firstly, after revisiting the controllability conditions of siphons and limitations of max and max' controlled-siphon properties, we define the max'' cs property and we prove that this new cs-property is not only sufficient but also a necessary liveness condition forgeneralized systems of simple sequential processes with resources (GS3PR). Moreover, we show how the checking of this property and hence liveness of GS3PR nets can be translaled into resolution of an integer programming (IP) model.Secondly, we propose a class of manufacturing-oriented Petri nets, M-nets for short, with strong modeling capability. Combining siphon control and the theory of regions, we develop a deadlock prevention method that makes a good trade-off between behavioral optimality and computational tractability Moreover, this thesis proposes a maximally permissive control policy for a subclass of Petri nets (calledBéta-nets) based on the token distribution pattern of unmarked siphons.Finally, we propose a designs method for robust liveness-enforcingsupervisors for AMS with unreliable resources appropriate in particular for systems of simple sequential processes with resources(S3PR)
53

Manufacturing System Improvement with Discrete Event Simulation : A case study with simulation applied to a manual manufacturing system

Gerdin, Erik, Rifve, Rebecca January 2018 (has links)
Due to a global increase in competitiveness in manufacturing,companies strive to increase the effectiveness of their manufacturing systems. The new industrial revolution, Industry 4.0, is a consequence inmotion to aid in creating improved manufacturing systems. A common tool within Industry 4.0 is simulation, where one could simulate changes in a virtual representation of a real world system. Discrete Event Simulation (DES) is a tool that has been widely adopted within industries to test manufacturing system changes virtually before implementing them physically. However, there is a need to discover the advantages, disadvantages and barriers to the application of simulation modeling in industry, as well as how to show the value with using the technique. A case study at the global manufacturing company Atlas Copco's plant In Tierp, Sweden has been undertaken with the purpose of using DES to aid a manufacturing plant in improving a manual manufacturing system, and how this could develop the current approach to a more long-term and sustainable one. Process mapping have been used to facilitate better understanding of the system prior to simulation modeling, as a manual system proved to be difficult to map otherwise. The results of this study points to that simulation can provide advantages of that decisions regarding implementation of system improvements could have better basis for being taken, simulation can be used to test system changes virtually to prevent eventual implementation problems, and simulation can be used as a tool to generate long-term solutions. However, disadvantages and barriers were identified as resistance from management in difficulties to convince the value of using simulation, extensive modeling competency required, and lack of the right prerequisites makes simulation modeling implementation more difficult. Further research should focus on uncovering the difficulties and barriers to the implementation of simulation modeling in industry, as this was not widely discussed in existing literature.
54

Modelagem e análise de performance de sistemas flexíveis de manufatura baseado em redes de Petri temporizadas: estudo de caso na indústria automobilística. / Modeling and performance analysis of flexible manufacturing systems using timed Petri nets: case study in automobilistic industry.

Rossini Sálvio Bomfim dos Santos 20 June 2008 (has links)
A necessidade de aumento de produção, da redução de custos e do aumento da qualidade de bens de consumo, tem motivado a constante evolução dos sistemas de produção, migrando os tradicionais sistemas de produção para os modernos e complexos sistemas de manufatura, onde a performance depende da eficiência dos equipamentos e do controle do processo. Por outro lado, a eficiência dos equipamentos depende de sua confiabilidade e manutenabilidade. Neste trabalho a análise de performance é avaliada com o uso de Rede de Petri p-t-Temporizada e através de simulações, incluindo a avaliação da confiabilidade do processo pela análise da otimização da saída do sistema, isto é, quantidade de itens produzidos. Nesta abordagem, uma lógica linear foi desenvolvida e validada utilizando-se uma comparação de resultados das classes de estados do algoritmo proposto com a ferramenta de simulação Tina para um modelo de um esquema produtor consumidor. Apresenta-se um estudo de caso na indústria automotiva, consistindo na análise dos problemas reais enfrentados em uma fábrica de carrocerias, com o uso da Rede de Petri p-t-Temporizada. / The necessity of growing in production, with reduction of costs and improvement in the quality of consumption good, has motivated the constant evolution of production systems, transforming traditional production systems into the modern and complex manufacturing systems, where the performance depends on the efficiency of the equipment and process control. On the other hand, the equipment efficiency depends of their reliability and maintainability. In this work it is proposed a performance evaluation and analysis with the use of p-t- Timed Petri Nets using simulations, including process reliability analysis of the system through the throughput optimization, i.e., produced amount of goods. In this approach, a linear logic statement was developed and validated using a comparison of results of classes of states between the Tina simulation environment and the algorithm considered for a model of a producing consuming system. A case study in the automotive industry is presented, consisting of the analysis of the real problems found in a body shop plant, with the use of Timed Petri Net.
55

Proposta de metodologias para integração de celulas de manufatura / Proposal for a methodology for integration of cellelar manufacturing

Paracencio, Luis Gustavo de Mello 14 August 2018 (has links)
Orientadores: Helder Anibal Hermini, João Mauricio Rosario / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-14T02:05:53Z (GMT). No. of bitstreams: 1 Paracencio_LuisGustavodeMello_D.pdf: 6716809 bytes, checksum: 4cd9dbc748f0f532de18ea5573d7c2fb (MD5) Previous issue date: 2009 / Resumo: Com o avanço tecnológico na área de engenharia mecatrônica, cada vez mais é necessário acompanhar e aperfeiçoar os estudos. Este trabalho pretende apresentar metodologias para integração de células de manufatura robotizadas com ênfase na modelagem e controle de um dispositivo robótico. O modelo do dispositivo em estudo é composto de três graus de liberdade acionados hidraulicamente, o que permite o posicionamento de uma mesa, onde uma peça possa ser trabalhada por dois robôs industriais, constituindo assim um sistema colaborativo de manufatura. São apresentados estudos referentes à modelagem cinemática e dinâmica, e ao cálculo dos parâmetros do sistema de controle utilizando MatLab-SimulinkTM. Foi desenvolvida uma interface em linguagem LabVIEWTM para aquisição e tratamento de informações provenientes dos sensores das juntas e da implementação do sistema de supervisão e controle. A partir da publicação de uma página de aplicação HTML, a célula colaborativa poderá ser disponibilizada na WEB, permitindo a criação de um laboratório virtual, direcionado à pesquisa científica e tecnológica e com possibilidade de se interligar com outros laboratórios de ensino e pesquisa. Isso permitirá, por exemplo, a realização de experiências e ensino à distância, executando tarefas complexas em tempo real / Abstract: In recent years, with technological advances in mechatronics engineering it is necessary to monitor and improve the studies of these new trends. This research aims to present a methodology to integrate robotic manufacturing cells with emphasis on modeling and controlling of a robotic device. The model of the device of this study consists of three degrees of freedom, driven hydraulically allowing the placement of a table where a piece can be worked by two industrial robots constituting a system of collaborative manufacturing. Studies are presented concerning kinematic and dynamic models and the calculation of parameters of the control system using MatLab-SimulinkTM. An interface was developed in LabVIEWTM language for acquisition and processing of the information from the sensors of the joints and the implementation of the system of supervision and control. Since the publication of an HTML page, a cell collaborative application may be available on the collaborative WEB allowing the creation of a virtual laboratory directed to scientific and technological research and the possibility to connect with other laboratories for teaching and research. For instance, this will allow carrying out the implementation of distance learning experience and performing complex tasks in real time / Doutorado / Mecanica dos Sólidos e Projeto Mecanico / Doutor em Engenharia Mecânica
56

Proposta de modelo para análise da integração da cadeia de suprimentos utilizando-se índices de automação / Proposed model for analysis of supply chain integration applying indices of automation

Perroni, Isa Maria da Penha Madeira 18 August 2018 (has links)
Orientador: Oswaldo Luiz Agostinho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-18T20:24:28Z (GMT). No. of bitstreams: 1 Perroni_IsaMariadaPenhaMadeira_M.pdf: 6601142 bytes, checksum: 9f1164593c8b5ceacb9522a30fb09f68 (MD5) Previous issue date: 2011 / Resumo: As organizações reconhecem que a integração intra e inter sistemas de manufatura é fundamental para manter-se não apenas competitivo, mas à frente da concorrência. O Sistema de manufatura pode ser visto como o conjunto de relações entre as atividades de Engenharia, Chão de Fábrica, Negócios e Suporte e suas sub atividades e, a sua Integração, entendida como o fluxo sinérgico de informação, pode ser alcançada ao se aplicar recursos de automação. Uma forma de analisar esta integração é através de Índices de Automação. O presente trabalho propõe o desenvolvimento de um modelo para análise de integração da cadeia de suprimentos baseado em índices de automação e para isto, considera a relação entre os sistemas de manufatura da empresa foco e seus primeiro nível de fornecedores. São apresentadas nove arquiteturas, divididas entre arquiteturas com capacidade de integração e arquiteturas sem capacidade de integração entre fornecedor e empresa. A aplicação do modelo de integração da cadeia de suprimento foi em uma Empresa foco do ramo de máquinas e implementos agrícolas e em três fornecedores primários, utilizando um questionário estruturado em 12 questões de múltipla escolha, referentes ao grau de automação das sub atividades de cada sistema de manufatura. A relação de integração da cadeia de suprimentos estudada se enquadra na arquitetura na qual a empresa foco não apresenta integração estrutural no sistema de manufatura e o primeiro nível de fornecedores apresenta integração estrutural das atividades no sistema de manufatura. Na conclusão, são propostas alternativas de integração para a cadeia de suprimentos e sugeridos trabalhos futuros / Abstract: The organizations recognize that integration within and between manufacturing systems is critical to maintain itself not only competitive, but ahead of the competition. The manufacturing system can be viewed as the set of relations between the activities of Engineering, Floor Factory, Business and Support and its sub-activities and their Integration, understood as the flow of synergistic information can be achieved by applying resources automation. A qualitative way to analyze this integration is through indices Automation. This paper proposes the development of a model for analysis of supply chain integration based on levels of automation and for this, consider the relationship between the manufacturing systems of the main company and its suppliers. Nine architectures are presented, divided in architectures with capability of integration between supplier and company and architectures without capability of integration between supplier and company. The application of the model of the supply chain integration will be in a main company of the field of agricultural machinery and implements and in three primary suppliers, using a questionnaire structured in 12 multiple choice questions, regarding to automation degree of the sub-activities of each manufacturing system. The relationship of integration of the studied supply chain fits in the architecture in which the main company has no structural integration in the manufacturing system and the supplier presents the structural integration of activities in the manufacturing system. In the conclusion, integration alternative for the supply chain are proposed and it is suggested future works / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica
57

Optimalizace pracoviště montáže cylindrických vložek s důrazem na ergonomii řešení a minimalizaci ztrát / Assembly workplace optimizationwith emphasis on ergonomy and loss minimization

Sobotka, Lubomír January 2011 (has links)
This diploma thesis describes optimization of assembly working place of cylinder locks brand FAB company ASSA ABLOY Rychnov, s.r.o. Theoretical part deals with universal process for designing manufacturing systems and for description of selected analytical and engineered methods and ergonomics .The practical part shows evaluation of current situation and create new time standards. in accordance with are designed 3 variants of the solution for lay out working place. For each variant is created simulation model, which is explore especially working load and automatic filling machine. The various options are compared by weight valuation and the most optimal is determined by maximal work in process and optimal warehouse supply of input components.
58

Racionalizace výrobního systému v podniku Prodia / Rationalization of a manufacturing system at Prodia company

Jakubec, Jan January 2014 (has links)
The work deals with the optimization of the production system in the engineering company Prodia s.r.o. There is a review of technological design in the introduction, the methods of analysis, design methods and capacity calculations are introduced. Subsequently, using these methods, the current state of material flows are analysed, the critical points in the production defined and design of new solution options to eliminate the main weaknesses identified during the analysis. Finally, an evaluation of the best variant and its economic profitability is introduced.
59

Optimal supervisory control of flexible manufacturing systems / Synthèse de contrôleurs optimaux pour les systèmes flexibles de production

Chen, Yufeng 07 July 2015 (has links)
Notre thèse est consacrée à l’étude de la supervision des réseaux de Petri en vue de la conception de systèmes manufacturiers flexibles. L’objectif est la définition de stratégies de pilotage en ligne pour l’évitement de conflits et d’interblocages, dans le cadre de la théorie de la supervision. Le point de départ de notre travail est d’exploiterle graphe de marquage du réseau de Petri, ce qui permet en particulier d’obtenir des stratégies de commande maximalement permissive pour des problèmes d’évitement de conflits et d’interblocages. Nous avons ainsi introduit des techniques originales, manipulations d’inégalités ou réductions d’ensembles de marquages, destinées à diminuerla complexité algorithmique d’une telle méthode. Dans premier temps, nous avons focalisé sur la synthèse de superviseurs dits purs, ce qui correspond au cas particulier où l’ensemble de marquage légaux, est convexe.Cette optimisation est ensuite considérée du point de vue de la facilité de mise en oeuvre. Nous traitons ainsi de la minimisation de la structure du superviseur et de son coût d’implémentation en préservant une structure de supervision qui offre à la fois la permissivité maximale et une complexité de calcul raisonnable en vue d’utilisationsur des installations réelles. Aussi, nous avons cherché à réduire le nombre de places de contrôle nécessaires pour réaliser un superviseur maximalement permissif, pour cela nous avons formule le calcul du nombre minimal de places de contrôle en termes d’un problème de programmation linéaire. Afin d’affaiblir la complexité de ce calcul de superviseur, deux versions de l’algorithme sont proposées. Ce problème de minimisation de la taille dusuperviseur, quoique fondamental, n’est pas abordé aussi directement dans la littérature. Il s’agit là d’une première contribution.Dans u second temps, nous nous sommes intéressés aux réseaux de Petri à boucles (self-loops). Les boucles étant représentées par une variable qui s’ajoute dans la contrainte inégalité définissant l’ensemble de marquages légaux. Après avoir proposé une méthode de réduction du nombre d’inégalités ainsi que du superviseur optimalen se basant sur les approches et résultats précédents, nous avons établi une condition suffisante d’obtention d’un superviseur maximalement permissif permettant de traiter des ensembles de marquages légaux non convexes.Enfin nous proposons une méthode de synthèse de contrôleur pour une nouvelle classe de réseaux de Petri, avec des arcs inhibiteurs correspondant à des contraintes définies par des intervalles. La taille du contrôleur ainsi obtenu et défini en termes d’arcs inhibiteurs à intervalles s’en trouve réduite ainsi que par conséquent sont coût d’implémentation. / Reachability graph analysis is an important technique for deadlockcontrol, which always suffers from a state explosion problem since it requires togenerate all or a part of reachable markings.Based on this technique, an optimal or suboptimal supervisor with high behavioralpermissiveness can always be achieved. This thesis focuses on designing liveness enforcing Petri net supervisors for FMSs by considering their behavioralpermissiveness, supervisory structure, and computationnal complexity.The following research contributions are made in this thesis.1. The design of a maximally permissive liveness-enforcing supervisor for an FMSis proposed by solving integer linear programming problems (ILPPs).2. Structural complexity is also an important issue for a maximally permissivePetri net supervisor. A deadlock prevention policy for FMSs is proposed, which canobtain a maximally permissive liveness-enforcing Petri net supervisor while thenumber of control places is compressed.3. In order to overcome the computational complexity problem in MCPP and ensurethat the controlled system is maximally permissive with a simple structure, wedevelop an iterative deadlock prevention policy and a modified version.4. We consider the hardware and software costs in the stage of controlimplementation of a deadlock prevention policy, aiming to obtain a maximallypermissive Petri net supervisor with the lowest implementation cost. A supervisorconsists of a set of control places and the arcs connecting control places totransitions. We assign an implementation cost for each control place and controland observation costs for each transition. Based on reachability graph analysis,maximal permissiveness can be achieved by designing place invariants that prohibitall FBMs but no legal markings.5. Self-loops are used to design maximally permissive supervisors. A self-loop ina Petri net cannot be mathematically represented by its incidence matrix. Wepresent a mathematical method to design a maximally permissive Petri netsupervisor that is expressed by a set of control places with self-loops. A controlplace with a self-loop can be represented by a constraint and a selfloopassociated with a transition whose firing may lead to an illegal marking.
60

Supervisor Synthesis for Automated Manufacturing Systems Based on Structure Theory of Petri Nets / Synthèse de contrôleurs de Systèmes de production automatisés basés sur la théorie structurelle des réseaux de Petri

Liu, Gaiyun 27 December 2014 (has links)
Le contrôle de systèmes industriels à cause de l’automatisation et la réduction de nombre des opérateurs devient un enjeu crucial. Les systèmes de production automatisés (AMS) sont d’autant plus touchés car une défaillance du programme de contrôle peut réduire considérablement la productivité voire entraîner l’arrêt du système de production. Pour certains de ces systèmes où le partage des ressources est pondérant, la notion de blocage partiel ou global est fréquente et la validation avant implantation est préférable pour réduire les risques.En raison de la capacité des réseaux de Petri à décrire aisément l’exécution concurrente des processus et le partage des ressources, de nombreuses méthodes de vérification d’absence de blocage et de synthèse de contrôleurs basées sur la théorie structurelle ou le graphe d’accessibilité des réseaux de Petri ont été proposées au cours des deux dernières décennies.Traditionnellement, une méthode de prévention de blocage est évaluée selon trois critères de performance: la complexité structurelle, la permissivité comportementale, et la complexité de calcul. Les méthodes fondées sur l’espace d’état aboutissent généralement à un contrôle maximal permissif mais souffrent de l'explosion combinatoire de l'espace d'états. En revanche, les méthodes de synthèse de contrôleurs fondées sur l’analyse structurelle évitent le problème de l’explosion de l’espace d’état mais aboutissent à des superviseurs pouvant restreindre considérablement les comportements admissibles du système. De plus si la théorie structurelle de contrôle de siphons pour la synthèse des superviseurs est mature dans le cas des réseaux de Petri ordinaires, elle est en développement pour les réseaux de Petri généralises. Par ailleurs, la plupart des travaux existants partent du principe que les ressources sont constamment disponibles. Or l’indisponibilité de ressources est en réalité un phénomène ordinaire. Il serait donc judicieux de développer une politique de vérification de blocage qui soit efficace tout en considérant des ressources non fiables.Cette thèse vise principalement à faire face aux limitations mentionnées ci-dessus. Nos principales contributions à la fois théoriques et algorithmiques sont les suivantes.Premièrement, après avoir revisité les conditions de contrôlabilité des siphons (cs–propriété) et précisé les limitations de la max cs- propriété et max’ cs- propriété, nous définissons la max’’ cs-propriété et nous démontrons que cette nouvelle propriété est une condition non seulement suffisante mais aussi nécessaire pour la vivacité de la classe des GS3PR (Generalized Systems of SimpleSequential Processes with Resources).Par la suite nous montrons comment le problème de la vérification de cette propriété et donc la vivacité des GS3PR peut se ramener à la résolution d’un programme linéaire en nombre entiers.Dans une seconde partie, nous proposons une classe de réseaux de Petri appelée M-Nets dotée d’une forte capacité de modélisation des systèmes de production automatisés. En combinant la théorie du contrôle siphon avec la théorie des régions, nous développons une méthode de prévention de blocage ayant un bon compromis entre l'optimalité du comportement et la complexité de calcul. De plus, nous proposons une méthode de synthèse d'un contrôleur maximal permissif pour une sous-classe de réseaux notée b-nets.Enfin, nous proposons dans cette thèse une méthode de conception d’un superviseur de systèmes de production automatisés où les ressources ne sont pas toutes fiables et particulièrement efficace pour la classe des S3PR (Systems of Simple Sequential Processes with Resources). / Because of automation and reduction of the number of operators, the control of industrial systems is becoming a critical issue. For automated manufacturing systems (AMS) where resource sharing is preponderant, the notion of partial or total blocking is frequent and validation before implementation is preferable to reduce the risks.Due to the easy and concise description of the concurrent execution of processes and the resource sharing by Petri nets, many methods to verify deadlock-freeness and to synthesize controllers using structural theory or reachability graph have been proposed over the past two decades.Traditionally, a deadlock control policy can be evaluated by three performance criteria : structural complexity, behavioral permissiveness, and computational complexity. Generally, deadlock control policies based on the state space analysis can approach the maximal permissive behavior, but suffer from the state explosionproblem. On the contrary deadlock control policies based on the structural analysis of Petri nets avoid in general the state explosion problem successfully, but cannot lead to the maximally or near maximally permissive controller. Morover, the current Deadlock control theory based on siphons is fairly mature for ordinary Petri nets,while for generalized Petri nets, it is presently at an early stage.On the other hand, most deadlock control policies based on Petri nets for AMS proceed on the premise that the resources in a system under consideration are reliable. Actually, resource failures are inevitable and common in most AMS, which may also cause processes to halt. Therefore, it is judicious to develop an effective and robust deadlock control policy considering unreliable resources.This thesis aims to cope with the limitations mentioned above. Our main theoretical and algorithmic contributions are the following. Firstly, after revisiting the controllability conditions of siphons and limitations of max and max' controlled-siphon properties, we define the max'' cs property and we prove that this new cs-property is not only sufficient but also a necessary liveness condition forgeneralized systems of simple sequential processes with resources (GS3PR). Moreover, we show how the checking of this property and hence liveness of GS3PR nets can be translaled into resolution of an integer programming (IP) model.Secondly, we propose a class of manufacturing-oriented Petri nets, M-nets for short, with strong modeling capability. Combining siphon control and the theory of regions, we develop a deadlock prevention method that makes a good trade-off between behavioral optimality and computational tractability Moreover, this thesis proposes a maximally permissive control policy for a subclass of Petri nets (calledBéta-nets) based on the token distribution pattern of unmarked siphons.Finally, we propose a designs method for robust liveness-enforcingsupervisors for AMS with unreliable resources appropriate in particular for systems of simple sequential processes with resources(S3PR)

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