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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.
1

Metodologia para modelagem, valida??o e programa??o de controladores l?gicos industriais usando statecharts b?sicos

Moura, Raimundo Santos 09 June 2009 (has links)
Made available in DSpace on 2014-12-17T14:54:52Z (GMT). No. of bitstreams: 1 RaimundoSM.pdf: 1084567 bytes, checksum: b0c04a2886a533d2f22958c9fda16e38 (MD5) Previous issue date: 2009-06-09 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Due of industrial informatics several attempts have been done to develop notations and semantics, which are used for classifying and describing different kind of system behavior, particularly in the modeling phase. Such attempts provide the infrastructure to resolve some real problems of engineering and construct practical systems that aim at, mainly, to increase the productivity, quality, and security of the process. Despite the many studies that have attempted to develop friendly methods for industrial controller programming, they are still programmed by conventional trial-and-error methods and, in practice, there is little written documentation on these systems. The ideal solution would be to use a computational environment that allows industrial engineers to implement the system using high-level language and that follows international standards. Accordingly, this work proposes a methodology for plant and control modelling of the discrete event systems that include sequential, parallel and timed operations, using a formalism based on Statecharts, denominated Basic Statechart (BSC). The methodology also permits automatic procedures to validate and implement these systems. To validate our methodology, we presented two case studies with typical examples of the manufacturing sector. The first example shows a sequential control for a tagged machine, which is used to illustrated dependences between the devices of the plant. In the second example, we discuss more than one strategy for controlling a manufacturing cell. The model with no control has 72 states (distinct configurations) and, the model with sequential control generated 20 different states, but they only act in 8 distinct configurations. The model with parallel control generated 210 different states, but these 210 configurations act only in 26 distinct configurations, therefore, one strategy control less restrictive than previous. Lastly, we presented one example for highlight the modular characteristic of our methodology, which it is very important to maintenance of applications. In this example, the sensors for identifying pieces in the plant were removed. So, changes in the control model are needed to transmit the information of the input buffer sensor to the others positions of the cell / Com o advento da inform?tica industrial muitos esfor?os t?m sido realizados para o desenvolvimento de nota??es e sem?nticas usadas para classificar e descrever diferentes tipos de sistemas, sobretudo na fase de modelagem. Tais esfor?os fornecem a infraestrutura necess?ria para a solu??o de alguns problemas reais de engenharia e a constru??o de sistemas pr?ticos que visam, principalmente, o aumento da produtividade, qualidade e seguran?a de processos. Al?m disso, apesar de muitos estudos tentarem desenvolverm?todos amig?veis para programa??o de controladores l?gicos industriais, estes ainda s?o programados atrav?s de m?todos convencionais no estilo tentativa e erro e, na pr?tica, usualmente n?o existe documenta??o escrita para esses sistemas. A solu??o ideal para este problema seria usar um ambiente computacional que permita engenheiros industriais implementar o sistema usando linguagens de alto n?vel e que obede?am padr?es internacionais. Baseado nessa perspectiva, este trabalho descreve um procedimento sistem?tico para modelar a planta e o controle de sistemas com din?mica discreta que incluem opera??es sequenciais, paralelas e temporizadas, usando um formalismo baseado nos Statecharts, denominado Statecharts B?sicos (SCB). A metodologia tamb?m permite procedimentos autom?ticos de verifica??o e implementa??o desses sistemas. A valida??o da metodologia foi realizada por meio de estudos de casos com exemplos t?picos de aplica??es da ?rea de manufatura. O primeiro exemplo apresenta um controle sequencial para um etiquetador de pe?as e serve para ilustrar a depend?ncia entre os dispositivos da planta. O segundo exemplo discute mais de uma estrat?gia de controle para uma c?lula de manufatura. O modelo da c?lula usada nos exemplos possui 72 configura??es poss?veis e, com um controle sequencial, a planta ficou restrita a 8 configura??es, enquanto que com um controle paralelo, a planta atuou em 26 configura??es diferentes, sendo, portanto, um controle menos restritivo. Por fim, foi apresentado um exemplo para ressaltar a caracter?stica modular da nossa metodologia, que ? de suma import?ncia para a manutenibilidade de aplica??es. Neste exemplo, os sensores para identifica??o de pe?as presentes na planta da c?lula de manufatura foram removidos, gerando a necessidade de altera??es no modelo do controle para propagar as informa??es do sensor de entrada de pe?as para as outras posi??es da c?lula.

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