In this study, an operational (short term) flexibility management approach is proposed for make-to-order companies with flexible shops. Order Review and Release (ORR) techniques and typical Flexible Manufacturing System (FMS) decisions are combined in this method. The proposed method prepares a shop environment by allocating process and routing flexibility types at different levels to the shop in each production cycle. Variety, volume, and criticality of the part types in the pool and the anticipated orders constitute the main inputs for flexibility allocation. A flexibility management policy is introduced and determination of the proper policy is realized with the integrated utilization of mathematical programming and simulation modeling. An experimental study is performed to investigate the effects of proposed method on a hypothetical flexible shop. Results show that with an appropriate policy, periodical and online flexibility management can be an effective tool to cope with uncertainty in demand if combined with ORR techniques.

Recent decades have been witness to explosive leaps in manufacturing productivity. Advances in communication technology, computing speed, control theory, and sensing technology have been significant contributors toward the increased productivity and efficiency that industry has exhibited. The continued growth of technological equipment and engineering knowledge challenges engineers to fully utilize these advancements in more sophisticated and useful automation systems. One such application involves enhancing bridge and gantry crane operation. These systems are used throughout the globe, and are critical aspects of industrial productivity. Consequently, improving the operational effectiveness of cranes can be extremely valuable. Effective control of cranes can be largely attributed to two distinct, but related aspects crane manipulation: 1) the expertise of operators, which are responsible for issuing commands to the structures, and 2) the dynamic properties of cranes, which influence how the structures respond to issued commands. Accordingly, the operational efficiency of cranes can be influenced by changing both the way that operators issue commands to cranes, and also how the crane responds to issued commands. This thesis is concerned with dynamic control theory of flexible machines, and human/machine interaction, especially as these areas relate to industrial crane control. In the area of dynamic control, this thesis investigates control strategies that are specifically suited for use on systems that possess common actuator nonlinearities, like saturation, rate limiting, dead-zone, backlash, and finite-state actuation. In the area of human/machine interaction, this thesis investigates the effects of different crane interface devices on the operational efficiency of cranes.

Made available in DSpace on 2016-06-02T19:05:23Z (GMT). No. of bitstreams: 1 DissEGRM.pdf: 5921557 bytes, checksum: 89005165cd9d839d8283e0713abe1fb8 (MD5) Previous issue date: 2005-05-30 / Financiadora de Estudos e Projetos / The Petri Net based Search has been shown as a promising way to solve Flexible manufacturing Systems (FMS) Scheduling Problem. However, the response time is critical since it s a system with high computational complexity. Focusing the reduction of response time, this work proposes a heuristic for Petri Net based Search to solve FMS Scheduling problem of makespan minimization. Experiments showed improvements on response time reduction comparing with prior works / Abordagens de Busca baseadas em Rede de Petri (PN) têm sido mostradas como uma forma promissora de resolver o problema da Programação da Produção de Sistemas Flexíveis de Manufatura (FMS). Entretanto, o tempo de resposta é crítico, uma vez que se trata de um sistema de alta complexidade computacional. Focando a redução do tempo de resposta do sistema, este trabalho propõe uma heurística para busca baseada em Rede de Petri para resolver o problema de programação de FMS na minimização do makespan. Experimentos mostraram um avanço na melhoria do tempo de resposta em relação a trabalhos anteriores

Made available in DSpace on 2016-06-02T19:06:03Z (GMT). No. of bitstreams: 1 4911.pdf: 4490259 bytes, checksum: 94cfbdb804ef2f55cb81e1163b1c6ad4 (MD5) Previous issue date: 2011-07-01 / Universidade Federal de Sao Carlos / Resources sharing is one of the main characteristics of Automated Manufacturing Systems (SMA), this characteristic can be a synonym of advantages but on the other hand it may lead to the problem of deadlock. Several papers have suggested methods and techniques to reduce or eliminate the occurrence of deadlocks in SMA systems. The deadlock resolution strategies suggested in the literature can be classified into the following types: deadlock detection and recovery, deadlock prevention and deadlock avoidance. This work proposes a resolution method for the control of automated manufacturing systems using colored Petri nets, the main goal of the proposed method is to provide a deadlock-free production controller. To model, simulate and implement the technique in a production controller a dedicated software is used to model the Petri Nets. Initially, a model using Colored Petri Nets is proposed, then changes in the model are introduced in order to eliminate the deadlocks, resulting in a Colored Petri net control model of the SMA. Finally the model is implemented in the scenario of a Flexible Manufacturing System for testing and validation of the method. / O Compartilhamento de recursos é uma das principais características dos Sistemas de Manufatura Automatizados (SMA), esta característica pode ser um sinônimo de vantagens, mas por outro lado pode levar ao problema de deadlock. Diversos trabalhos têm sugerido métodos e técnicas para reduzir ou eliminar a ocorrência de deadlocks em SMA. As estratégias de resolução de deadlock sugerido na literatura podem ser classificados nos seguintes tipos: detecção e recuperação de deadlocks, prevenção de deadlocks e de deadlock. Este trabalho propõe um método de resolução para o controle de sistemas de manufatura automatizados utilizando redes de Petri coloridas, o principal objetivo do método proposto é obter um controlador da produção livre de deadlocks. Para modelar, simular e implementar a técnica em um controlador de produção um software dedicado é usado para modelar a rede de Petri. Inicialmente, um modelo usando Redes de Petri Coloridas é proposto, então mudanças são introduzidas, a fim de eliminar os deadlocks, resultando em um modelo de rede de Petri de um SMA livre de deadlock. Finalmente o modelo é implementado no cenário de um Sistema de Manufatura Flexível para testes e validação do método.

Made available in DSpace on 2016-06-02T19:06:23Z (GMT). No. of bitstreams: 1 DissJCD.pdf: 3954079 bytes, checksum: 63ef4f081a962ca21478327fb623632d (MD5) Previous issue date: 2004-08-25 / Flexible manufacturing systems (FMS) have been designed to meet market requirements that demand products that are quality and ready to deliver. In order to meet the market requirements, the methodologies used in the FMS scheduling must consider a highly dynamic environment, where it is often necessary to meet or to react to uncertain demands and to get better use of its resources. An on-line scheduling procedure based on fuzzy logic is proposed in this work, whose main characteristic is shop floor tasks scheduling using fuzzy rules building with the support of an expert to meet several measures of performance. A simulation study was carried out with the objective to verify the applicability of the proposed approach, using a simulation tool integrated with the on-line scheduling procedure based on fuzzy logic. / Os sistemas flexíveis de manufatura (FMS) têm sido projetados para atender as necessidades do mercado, que demandam por produtos que apresentam qualidade e prazos de entrega pequenos. Para atender as necessidades do mercado, as metodologias usadas na programação de operações de FMS devem considerar um ambiente altamente dinâmico, onde é frequentemente necessário atender ou reagir a demandas incertas e fazer o melhor uso de seus recursos. Um procedimento de programação on-line baseado em lógica fuzzy é proposto neste trabalho, cuja característica principal é programar as tarefas do chão de fábrica utilizando regras fuzzy construídas com o apoio de um especialista para atender a várias medidas de desempenho simultaneamente. Um estudo por meio de simulação foi realizado com o objetivo de verificar a aplicabilidade da abordagem proposta, utilizando uma ferramenta de simulação integrada ao procedimento de programação on-line baseado em lógica fuzzy.

Orientador: Antonio Batocchio / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-08T16:29:28Z (GMT). No. of bitstreams: 1 Pinto_ClaudioRicardoMonteiro_M.pdf: 1016323 bytes, checksum: 092608f0049fe6576d6787fc00dd93ca (MD5) Previous issue date: 2006 / Resumo: Atualmente o aumento da competitividade industrial e da concorrência, está gerando uma busca constante de produtos inovadores e de baixo custo. Alguns seguimentos industriais também tem sentido o poder das 'commodities', onde grande parte dos custos envolvidos nos processos, principalmente matérias-primas, não são de controle da empresa dificultando e reduzindo a sua margem de atuação frente a concorrência. Existem diversas técnicas administrativas que demonstram excelentes resultados com as suas implementações, como a Teoria das Restrições (TOC), Manufatura Enxuta, Manufatura Agil, etc e estes sistemas podem ser tratados de forma integrada e comparativa (Godinho Fº e Fernandes, 2005). O objetivo deste trabalho é avaliar a aplicação destas ferramentas em uma empresa com regime de produção semi-contínuo de condutores elétricos, analisando os resultados das implementações realizadas através de métricas aplicadas ao setor. A Empresa estudada é uma empresa multinacional do ramo Eletroeletrônico, mais especificamente Condutores Elétricos, que atua principalmente no segmento de Energia e a linha de produtos selecionada para este estudo foi a de cabos flexíveis. Realizou-se o levantamento do fluxo de valor da empresa adotando a metodologia da Manufatura Enxuta e avaliou-se o impacto de cada fase do processo em relação ao processo como um todo, através deste levantamento determinou-se o ponto de restrição do sistema, e a partir daí foram definidas algumas ações de controle, como kanban, supermercado de peças e planos de manutenção preventiva nos equipamentos. Como resultado atingiu-se um incremento de 100% de capacidade de fabricação de cabos flexíveis com um aumento de produtividade na ordem de 90%, uma redução do nível de inventário de 33% e uma melhoria de qualidade com a redução de 20% no nível de ppm?s gerados por falhas. Outro fator importante foi a redução no tempo de dimensionamento e implementação dos novos processos com o auxílio da Simulação por computador. Foi possível observar que é viável o uso conjunto da TOC e da Manufatura Enxuta comprovando a aplicabilidade destas teorias em um processo de fabricação de condutores elétricos / Abstract: The increasing degree of industrial competitivity and competition has been generating recently a constant search for innovative and low-cost products. Some industrial segments have also been affected by the power of 'commodities', in relation to which a significant part of process-related costs, chiefly raw-materials, are not controlled by the enterprise, something that makes difficult and reduces its margins for maneuver before competition. There are several managing techniques that present optimum implementation results, as is the case of the Theory of Constraints - TOC), Lean Manufacturing and Agile Manufacture, systems that can be approached in a integrated and comparative way (Godinho Fº e Fernandes, 2005). This work aims to evaluate the application of these tools in a company producing electric conductors in a semi-continuous production regime by means of the evaluation the results of implementations introduced by metrics applied to the sector. The Enterprise studied is an Electronics multinational that produces electrical conductors, chiefly for the Power segment, and we selected for this study the production of flexible cables. The value flow of the company was evaluated adopting the "Lean Manufacture" philosophy and we examined the impact of each phase of the process in relation to the process as a whole. This survey allowed determining the system?s point of restriction, and the identification of the system?s restrictions allowed to define some controlling actions, like kanban, parts supermarket and preventive equipment-maintenance plans. As a result, an increment of 100% in manufacture capacity of flexible cables was reached, with an increase in productivity of 90%, a reduction in the level of inventory of 33% and a quality improvement with the reduction of 20% in the level of failure-induced PPMs. Another important factor was the reduction in the time of dimensioning and implementation of the new processes with the help of computer-based simulation. The work showed the joint use of TOC and Lean Manufacturing to be possible, proving these theories to be applicable to a manufacturing process of electric cables production / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

Este trabalho tem por objetivo atualizar um Sistema Flexível de Manufatura, (SFM) didático, que devido às suas características construtivas apresentava inúmeras dificuldades de operação e manutenção, necessitando sempre de mão de obra altamente especializada. As dificuldades com a manutenção tornavam o SFM totalmente inoperante para a utilização nas aulas de uma das unidades da escola SENAI, o que prejudicava as atividades práticas, em laboratório, das disciplinas do curso técnico da área de produção. O projeto deste trabalho consistiu em uma reengenharia completa da parte elétrica de um Veículo Guiado Automaticamente (AGV) como também no desenvolvimento de um sistema supervisório, que comanda a comunicação entre os CNCs, AGV e computadores. Após as modificações efetuadas, os alunos das disciplinas da área de produção poderão interagir com o sistema, modificando a logística de produção conforme as necessidades didáticas a serem estudadas. Por outro lado os alunos de automação, por meio do acesso à documentação e à estrutura do sistema de manufatura, poderão desenvolver estudos e possíveis modificações, uma vez que o sistema se tornou mais didático e amigável. / This paper aims to update a didactic Flexible Manufacturing System (FMS) that due to their construction had numerous difficulties in operation and maintenance, and so constantly require manpower to operate and maintain highly specialized. The difficulties with maintaining the SFM became totally irrelevant, for use in the classroom of an unit school SENAI, would hinder the practical activities in the disciplines of laboratory technician course from the production area. The design of this work consisted in re-engineering of the complete electrical part of an Automatically Guided Vehicle (AGV) and development of a supervisory system and communication between the CNCs, AGV and computers. After the modifications to the students of the disciplines of production may interact with the system by modifying the production logistics as required didactic to be studied. Furthermore students automation through access to documentation and structure of the manufacturing system can develop studies and possible changes, since the system became more didactic and friendly.

No description available.

Industry 4.0 has caused exceptional changes in the industrial world. A relevant breakthrough is the concept of Cyber-Physical Production System (CPPS) which involves a system of interconnected entities with the main objective of achieving flexibility, which is essential for the manufacturing industries to remain competitive due to the actual demand for customization. The project suggests the use of a robot cell distribution called robot island as a solution to address this problem. In the implementation, a virtual model and program will be presented with flexible mobile robots, AGVs and a PLC. All are designed following the three principles of the CPS using RobotStudio and CODESYS to simulate and evaluate the results. The research demonstrates how autonomous, modular, flexible and adaptable to changes in product or production process system is, for example with the integration of the concept of the resource pool and variations in the product characteristics. The resulting executable is made with standardised modules so it can be extrapolated to other manufacturing processes, opening a wide range of possibilities for this island of robots. / <p>Utbytesstudenter</p>

<p>Textiles have gained popularity in wearable products due to their potential for wearability, comfort, flexibility, breathability, and seamless fit to the human body. The growing demand for remote telehealth monitoring has led to advancements in the field of e-textiles. Various approaches, such as dip coating, screen printing, inkjet printing, and vapor deposition, are utilized to overcoat fabrics with active nanomaterials. However, practical deployment still faces challenges due to a lack of rapid prototyping for scalable and customizable e-textiles. To meet the requirements of large-scale batch production, high-resolution electrode line width, and long-term durability, new platform technologies have been established to convert existing textiles into multifunctional e-textiles. These studies have also revealed the process-structure-property relationships of various e-textiles.</p> <p>Chapter I overviews the recent results and current limitations of e-textiles in wearable sensing and display. Since people stay and work in various circumstances, continuous monitoring of physical, electrophysiological signals on skin in ambulatory manners is necessary to evaluate hazardous situation or chronicle symptoms. For these reasons, fabrication of smart e-textiles is crucial. In this chapter, various conductive materials, overcoating methods, and sensor structures for physical and electrophysiological sensors are reviewed. In addition, as a useful user communication tool with different sensor system, e-textile formats of displays are developed. The comprehensive e-textile displays from DC-driven to AC-driven are presented.</p> <p>Chapter II introduces a dual-regime spray technique that enables the direct writing of functional nanoparticles onto commercial 4-way stretchable textiles up to a meter scale with high-resolution mask-free patterning. The resulting e-textiles maintain the intrinsic properties of the fabric and can conform to various body shapes, enabling high-fidelity recording of physiological and electrophysiological signals under ambulatory conditions. Field tests have shown the potential of these e-textiles for minimally obtrusive remote telehealth monitoring of large animals.</p> <p>Chapter III presents an in-situ polymerization and patterning technique that utilizes the dual-regime spray method to synthesize conductive polymers directly onto commercial stretch textiles. The resulting e-textiles are utilized for strain sensors that conform closely to the human body, providing exceptional measurement accuracy and fidelity in capturing physical signals and motion detections.</p> <p>Conclusion section summarizes this dissertation with pointing out important results and discussions of each study. As an innovative additive manufacturing technology, dual-regime spray system, was established and developed to open new field in manufacture of e-textile. At last of this section, the potential research opportunities and perspectives are addressed. </p>