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Electroactive polymers are a class of materials capable of reallocating their shape in response to an electric field while also having the ability to harvest electrical energy when the materials are mechanically deformed. Electroactive polymers can therefore be used as sensors, actuators, and energy harvesters. The parameters for manufacturing flexible electroactive polymers are complex and rate limiting due to number of steps, their necessity, and time intensity of each step. Successful additive manufacturing processes for electroactive polymers will allow for scalability and flexibility beyond current limitations, advancing the field, opening additional manufacturing possibilities, and increasing output. The goal for this research was to use additive manufacturing techniques to print conductive and dielectric substrates for building flexible circuits and sensors. Printing flexible conductive layers and substrates together allows for added creativity in design and application.

Well-behaved SNC covers well-behaved and various classes of FC (free-choice) and is not included in AC (asymmetric choice). An SNC allows internal choices and concurrency and hence is powerful for irodeling. Any SNC is bounded and its liveness conditions are simple. An integrated algorithm, has been presented for verification of a net being SNC and its liveness with polynomial time complexity. Scholars often need to verify properties on nets appearing in literatures. Verification by CAD tool is less desirable than that by hand due to the extra efforts to input the model aid learn to use the tool. We propose to manually search the maximum SNC component followed by locating bad siphons in an incremental manner. We then apply Lautenback's Maridng Condition (MC) for liveness to berify the property of liveness. But there are two drawbacks associated with the above MC. First, it guarantees only deadlock-freeness, and not necessary liveness. We have identified the structure cause for this and developed its livess conditions correspondingly. Second a net may be live even if the MC is not satisfied. We have identified the structure cause for this. The MC has been readjusted based on our proposed new theorey.

Today's manufacturing environment is characterized by competition and continuous change in product and process requirements. The concept of "design for manufacturability" integrates product specifications with manufacturing capabilities by considering the design and manufacturing phases as an integrated system, evaluating the combined system during the design phase of a product , and adjusting the design for maximum efficiency and production economics. This research focuses on one aspect of design for manufacturability, that of process technology evaluation for a specified product design. The objective of the proposed system developed in this study is to evaluate technology alternatives for manufacturing a specified part design and to identify the best combination of product-process characteristics that would minimize production costs within the constraints set by the product's functional requirements and available processing technology. The research objectives are accomplished by developing a simulation based analysis system. The user inputs product specifications through structural screens. The system maintains data bases of work and tool materials, and machining operations. Based on user input, the system then extracts appropriate information from these data bases, and analyzes of the production system in terms of production economics, and other operational measures such as throughput times and work-in-process inventories. Sensitivity analysis may then be performed to explore tradeoffs in design and production parameters. The system is completely integrated, and a user with no prior experience of either simulation or data base technology can use the system effectively. / Graduation date: 1992

In this study a time based bidding framework is developed which is used for dispatching jobs to manufacturing resources in a virtual shop-floor environment. Agent-based shop-floor control approach is implemented with machine and part agents. The Contract-net communication protocol is utilized as the negotiation scheme between these agents. Single step product reservation (SSPR) technique is adopted throughout the study. Primary objective is determined as meeting the due dates and if the lateness is inevitable, avoiding the parts of high priority from being late. A balanced machine utilization rate is set as the secondary objective. During bid construction step, the SSPR technique is augmented with W(SPT+CR) sequencing rule in order to obtain weighted tardiness results. Bids containing Earliest Finishing Time (EFT) and machine loading values of the corresponding machine are evaluated with considering the priority of the part. An elimination algorithm which discards the highly deviated bids having obvious differences is implemented at the initial stage of the bid evaluation step. A basic algorithm to control the maximum tardiness value is applied, as well. A simulation test bed is developed in order to implement the time concept into the presented bidding framework. The test bed is mainly based on the Computer Integrated Manufacturing Laboratory (CIMLAB) located in Middle East Technical University, Department of Mechanical Engineering. The developed bidding algorithm is tested under several cases. Results revealed that the proposed bidding framework was quite successful in meeting the objectives. The study is concluded with some specific future work, outlined in the light of the results obtained.

Advanced material handling systems' impact on flexible manufacturing systems (FMS) have increased the efficiency and work rate over conventional manufacturing assemblies. The interaction of automated guided vehicles (AGVs), roller conveyors and conveyor belts with robots and machine tools forms highly sophisticated assembly operations. Whilst material handling in FMS today is conventionally used to transport assembly units from one work station to another, it does not take an active role in the manufacturing process. With manufacturers implementing more advanced manufacturing principles to perform agile manufacturing, there is a growing need to implement "smarter" material handling systems that would perform essential, integral roles in the assembly process. This research outlines the development of a cordless linear synchronous motor (CLSM) material handling system. The CLSM incorporates a permanent magnet courier that moves without tether restrictions on an integrated reverse air bearing system which eliminates friction. The CLSM provides a material handling system with enhanced travel, flexibility and accuracy. The CLSM material handling system is designed to integrate with overhead manipulators and part feeders to form a comprehensive flexible manufacturing system. This research covers the 2-D finite element modeling (FEM) used to determine the CLSM's optimal parameters. The development of the motor windings design and construction, together with the control system for the CLSM, is also covered. The CLSM novel air bearing system is outlined and compared to other conventional linear bearing systems. The possible impact of the CLSM on current manufacturing systems is explored to determine the validity of the research project and possible further research opportunities. / Thesis (M.Sc.Eng)-University of Natal, Durban, 2000.

Made available in DSpace on 2016-06-02T19:05:17Z (GMT). No. of bitstreams: 1 DissRWCM.pdf: 3820933 bytes, checksum: 0defe423c2e4d7d5969558fc1677062d (MD5) Previous issue date: 2005-08-26 / In order to attend the market quickly, a company need to have flexibility and to change its production line, to assist to the production of personalized products, to change the raw material or, even, the conception of the product like in an automatic system of manufacture. Administration of processes, industrial automation and IT (Information Technology) are essential to guarantee not only the companies, competitiveness but their survival inside of this scenery. The larger interest among the automatic systems of manufacture in this work is the flexible manufacture system (FMS), for its inclusion and complexity and, consequently, its control and the variety of architectures, as the centralized, the hierarchical, the heterarchical, the hybrid and, finally the multi - agent, therefore the main focus of this work will be the control system of a FMS. So one of the architecture alternatives, is the proposal using a system of hybrid control, because it allows the communication among levels, by sidelong, and the modules involved in the production process and factory ground control, so it will be possible, to determine which are the instances or moments so of decision, describing the used functions, as well as the treated information. To make possible the modeling modules are used: manager, selective and movement controller facilitating the construction of a structured algorithm aiming at the detail of the process mapping of communication about the actions unchained in the factory ground. / Para uma empresa responder mais rapidamente ao mercado, é importante ter flexibilidade e poder mudar sua linha de produção facilmente, para atender à fabricação de produtos personalizados, alterar a matéria-prima ou, até mesmo, a concepção do produto como em um sistema automático de manufatura. Gerenciamento de processos, automação industrial e TI (Tecnologia da Informação) são essenciais para garantir não somente competitividade das empresas, mas sua sobrevivência dentro deste cenário. Dentre os sistemas automáticos de manufatura que têm sido abordados, o de maior interesse para o escopo deste trabalho é o sistema flexível de manufatura (FMS), por sua abrangência e complexidade e, conseqüentemente, seu controle. Há uma variedade de arquiteturas de controle, como a centralizada, a hierárquica, a heterárquica, a híbrida e, finalmente a multi agente, com vantagens e desvantagens em relação à facilidade de modelagem, implementação e desempenho. Como proposta deste trabalho é estudada uma das alternativas de arquitetura, utilizando um sistema de controle híbrido, pelo fato do mesmo permitir a comunicação entre níveis, tanto lateralmente, como com os módulos envolvidos no processo de fabricação e controle de chão de fábrica. Será possível com isto, determinar quais são as instâncias ou momentos de tomada de decisão, descrevendo as funções utilizadas, bem como as informações tratadas. Para viabilizar a modelagem utilizam-se módulos: gerenciador, seletivo e controlador de movimentação facilitando a construção de um algoritmo estruturado objetivando o detalhamento do mapeamento do processo de comunicação das ações desencadeadas no chão de fábrica.

Orientador: João Maurício Rosário / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-17T01:25:49Z (GMT). No. of bitstreams: 1 CastilloEstepa_RicardoAndres_M.pdf: 7409956 bytes, checksum: 80c4bd559f383881e7ad078cc2d08dad (MD5) Previous issue date: 2010 / Resumo: Este trabalho propõe uma arquitetura genérica de supervisão e comando para uma plataforma automatizada de experimentação modular com capacidade de utilização remota, concebida para apoiar e complementar os processos de formação e pesquisa em Automação Industrial e Robótica, descrevendo sua concepção, modelagem dinâmica e implementação hardware - software. A integração de tecnologias e dispositivos industriais existentes no mercado (Controladores Lógicos Programáveis - CLP, diversos tipos de sensores e atuadores industriais, processamento de imagens, sistemas supervisórios e dispositivos robóticos de movimentação) em uma única plataforma implementada através de uma arquitetura modular de Sistema Automatizado de Produção Colaborativo (CSAP/ADACOR) permite que alunos e pesquisadores possam interatuar com essas tecnologias realizando atividades de modo a automatizar, supervisar e comandar um processo completo de produção. Uma plataforma desenvolvida utilizando esta arquitetura genérica permite aos estudantes e pesquisadores trabalhar dentro de um ambiente educacional, mas que retrata a maioria dos aspectos encontrados em um Sistema Automatizado de Manufatura real, tais como Integração Tecnológica, Redes de Comunicação, Controle de Processos e Gestão da Produção. Além disso, é possível realizar o controle e supervisão do processo completo que ocorre na plataforma automatizada por meio de uma conexão remota que utiliza a internet - WEBLAB (Laboratório Remoto); possibilitando que usuários e grupos em diferentes lugares possam utilizar a plataforma e compartilhar informação rapidamente. Pode-se destacar também que as características de Modularidade e Flexibilidade da plataforma permitem futuras modificações tanto do software quanto do hardware da mesma / Abstract: This work proposes a generic supervisory and command architecture for an experimentation modular automated platform equipped with remote access capacities which is conceived with the aim of improve training and research processes on Automation and Robotics, this study describes the platform's design, dynamic modeling and implementation stages. The technologic and industrial devices integration (Programmable Logic Controllers - PLC, several types of sensors and actuators, image processing, supervisory systems and robotic manipulation devices) in a single platform which is implemented following a modular Collaborative Automatic Production System (CAPS/ADACOR) architecture allows students and researchers to Interact with it by means of doing practices in order to successfully automate, supervise and manage a complete production process. Therefore, class acquired theoretical concepts are supported so improving user's professional skills. A platform developed using the here proposed generic structure allows users to work within an educational environment coping with most of the encountered aspects in a real Manufacturing Automation System, such as Technologic Integration, Communication Networks, Process Control and Production Management. Furthermore it is possible to command the entire assembly process taking place at the platform by a remote network connection using the internet - WEBLAB (Remote Laboratory), enabling individual users and groups in different places in order to use the platform and quickly interchange information. In addition it is important to outstand that both the Modularity and Flexibility of the platform can allow readily any further hardware or software enhancement / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica

Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2018-02-15T15:02:41Z No. of bitstreams: 2 Dissertação - Thiago de Almeida Bastos -2018 .pdf: 2834099 bytes, checksum: 20704146dd6e29dc70c067fcbd0011a2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-02-16T09:38:12Z (GMT) No. of bitstreams: 2 Dissertação - Thiago de Almeida Bastos -2018 .pdf: 2834099 bytes, checksum: 20704146dd6e29dc70c067fcbd0011a2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-16T09:38:12Z (GMT). No. of bitstreams: 2 Dissertação - Thiago de Almeida Bastos -2018 .pdf: 2834099 bytes, checksum: 20704146dd6e29dc70c067fcbd0011a2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-01-30 / This master's thesis seeks to contribute to the automation of production lines, and proposes a methodology for the formal verification of flexible manufacturing models by the Petri-PDL tool. The Petri-PDL framework is based on a multimodal logic associated with a scheme defined for the problem with the Petri nets to specify and model sequential problems demonstrating in logical proofs the correctness of properties inferred by the model. This formal treatment is adapted for the treatment of flexible sequential processes, since these models are used in many other applications with Petri nets. They will be considered models of flexible production system found in the systematic review to evaluate the efficiency of its model and its adaptation to this formal refinement. / Este trabalho busca contribuir com a automação de linhas de produção e propõe uma metodologia para a verificação formal de modelos de manufatura flexível a partir da ferramenta Petri-PDL. O conceito Petri-PDL baseia-se em uma lógica multimodal associada ao esquema definido para o problema com as redes de Petri para especificar e modelar problemas sequenciais demonstrando em provas lógicas a corretude de propriedades inferidas pelo modelo. Este tratamento formal será adaptado para o tratamento de processos sequenciais flexíveis, uma vez que estes modelos são usados em muitas outras aplicações com redes de Petri. Serão considerados modelos de sistema de produção flexível encontrados na revisão sistemática para avaliar a eficiência de seu modelo e sua adaptação a este refinamento formal.

Manufacturing systems have developed both physically and technologically, allowing production of innovative new products in a shorter lead time, to meet the 21st century market demand. Flexible flow lines for instance use flexible entities to generate multiple product variants using the same routing. However, the variability within the flow line is asynchronous and stochastic, causing disruptions to the throughput rate. Current autonomous variability control approaches decentralise the autonomous decision allowing quick response in a dynamic environment. However, they have limitations, e.g., uncertainty that the decision is globally optimal and applicability to limited decisions. This research presents a novel formula-based autonomous control method centered on an empirical study of the effect of stochastic variability on the performance of flexible human-dependent serial flow lines. At the process level, normal distribution was used and generic nonlinear terms were then derived to represent the asynchronous variability at the flow line level. These terms were shortlisted based on their impact on the throughput rate and used to develop the formula using data mining techniques. The developed standalone formulas for the throughput rate of synchronous and asynchronous human-dependent flow lines gave steady and accurate results, higher than closest rivals, across a wide range of test data sets. Validation with continuous data from a real-world case study gave a mean absolute percentage error of 5%. The formula-based autonomous control method quantifies the impact of changes in decision variables, e.g., routing, arrival rate, etc., on the global delivery performance target, i.e., throughput, and recommends the optimal decisions independent of the performance measures of the current state. This approach gives robust decisions using pre-identified relationships and targets a wider range of decision variables. The performance of the developed autonomous control method was successfully validated for process, routing and product decisions using a standard 3x3 flexible flow line model and the real-world case study. The method was able to consistently reach the optimal decisions that improve local and global performance targets, i.e., throughput, queues and utilisation efficiency, for static and dynamic situations. For the case of parallel processing which the formula cannot handle, a hybrid autonomous control method, integrating the formula-based and an existing autonomous control method, i.e., QLE, was developed and validated.