Simulation and optimisation of a specific flexible manufacturing system.

As current market competition evolves, most companies intend to increase their options for product customisation and accelerate their product upgrading. Correspondingly, manufacturers have to face the increasing size of product family, shortened product life cycle or rapid product/process change. Therefore, Flexible Manufacturing Systems (FMS) have been introduced that uses advanced machines and efficient transport systems to produce multiple products at the same time. However, an FMS can be complicated to manage because of the increased variability in products and processes. The research aims to develop manufacturing simulation and optimisation techniques for a FMS. This research will integrate Discrete Event Simulation (DES) and multi-objective optimisation approach to address the complexity and flexibility within an agile manufacturing environment. Due to the complexity of FMS, most current FMS optimisation research has engaged with FMS production problems separately without considering other inter-related problems in the same system such as dealing with operation sequence problem without considering Level of Flexibility (LoF), thus it is hard for the solution to provide a prospective impact for the whole system. There are very few real-world FMS implementations that are available to literatures, making it difficult to build and verify the models within a complete ecosystem. Consequently, most of the models in the research are oversimplified. Therefore, this research aims to develop a method to optimise FMS production considering the overall system, by having access to an FMS industrial implementation. This research contributes to knowledge in four main areas, namely, (1) the interactions of FMS production problems have been investigated, (2) a framework has been developed to integrate the simulation and optimisation for FMS to enable optimisation algorithms working with DES models effectively, (3) a comprehensive FMS simulation model has been built and validated on the industrial shop floor and (4) multi-objective optimisation has been applied to the FMS scheduling problem, considering interactions with other problems. Based on the results and limitations of this research, real-time simulation, mock-up FMS and improve computational efficiency are suggested for future work.PhD in Manufacturin

Aplicação de ferramentas Lean e produção celular numa empresa de artigos para escritório

Dissertação de mestrado integrado em Engenharia e Gestão IndustrialA presente dissertação enquadra-se no âmbito do Projeto de Dissertação inserido no Mestrado Integrado em Engenharia e Gestão Industrial da Universidade do Minho, referente ao 5º ano, 2º semestre. Este projeto teve como principal objetivo a aplicação de ferramentas Lean Production e celular numa empresa de artigos para escritório, ACCO Brands. A metodologia de investigação usada foi a Action Research, sendo seguidos os 5 passos associados a esta metodologia. Assim, a investigação iniciou-se com uma revisão bibliográfica sobre Lean Production, história, princípios, desperdícios associados ao Lean Thinking e benefícios da implementação e principais ferramentas usadas nesta temática, tais como os 5S, a Gestão Visual, o Kaizen, Just-In-Time ou o Standard Work. Foram ainda abordados o problema de reconfiguração classificação de sistemas produtivos e projeto de sistemas orientados ao produto, apresentando-se alguns casos de sucesso. O diagnóstico da empresa foi iniciado com uma apresentação e caracterização da empresa, referindo os vários setores, seguida de uma análise mais pormenorizada da secção em estudo. Devido à importância revelada pela empresa no novo projeto de máquinas de encadernação, denominado Projeto Phoenix, o estudo recaiu sobre os modelos constituintes do mesmo, sendo focada a análise destes produtos, mais propriamente na família ECO. Deste modo, realizaram-se várias análises, das quais se destacam: tempos de ciclo das operações, cadeia de valor, atividades nos postos de trabalho, distâncias percorridas e competências, sendo identificados alguns aspetos que poderiam ser melhorados. Após a identificação dos problemas apresentaram-se propostas de melhorias, sendo algumas implementadas, nomeadamente, o balanceamento da linha, alterações de postos de trabalho nesta e implementação de documentação normalizada. Contudo, outras propostas não foram implementadas, por exemplo, a proposta da célula em U. Os resultados mais relevantes da implementação das propostas foram a redução de 2 operadores (aumento da produtividade de 6,4 para cerca de 8,2 peças/hora.homem) e a eliminação de operações que não acrescentavam valor. Foi proposto um abastecimento por um comboio logístico, que reduziria as distâncias percorridas em, aproximadamente, 4Km/dia e o tempo de abastecimento em 2 h/dia, passando estas atividades a serem realizadas por um elemento do stock. Os ganhos monetários expectáveis relacionados com estas propostas seriam na ordem dos 21906€ por semana.This dissertation of the Integrated Master in Industrial Engineering and Management, University of Minho, 5th year, 2nd semester was developed in ACCO Brands company. This project had as the main aim the implementation of Lean Production and cellular tools in an assembly line of office products. The research methodology used was the Action Research, which followed the 5 steps involved in this methodology. Thus, the research began with a literature review of Lean Production, history, principles, wastes, Lean Thinking and benefits of implementing Lean, as well the main tools used such as 5S, Visual Management, Kaizen, Just-In-Time or Standard Work. It was also introduced the problem of production system reconfiguration and classification and product-oriented systems design, presenting some successful cases of this reconfiguration. The diagnosis of the company started with a presentation and characterization of the company, referring to the various sectors, followed by a more detailed analysis of this project, the assembly line. As the company gave much importance to the new project of binding machines, called Project Phoenix, the study fell on the constituents of the same models, with focused analysis of these products, more specifically in the ECO family. Thus, there have been several analyzes, which were: times of operations, value chain activities in the workplace, distances traveled and skills of operators. This way, some aspects that could be improved were identified. After identifying the problems, some proposals were presented for improvements, some of them being implemented, namely, the line balancing, changes on operations of assembly line and implementation of the standard documentation. However, others proposals weren't implemented, for example, the proposal of a U cell. The most relevant results of the implementation of the proposals were the reduction of 2 operators (productivity increase from 6.4 to about 8.2 machines/h.h) and elimination of operations which did not add value. Also, it was proposed a supply system by a milk-run, reducing the distances traveled by approximately 4Km/day and supply time of 2 h/day, passing these activities to be performed by a member of the stock in order to supply several sections. The expected monetary gains associated with these proposals were, approximately, 21906€ per week (including gains on proposals implemented and not implemented)