The objective of the thesis is rationalization of current process of assembling of manifold assemblies from the reduction of operating costs point of view. The reason for rationalization is uncompetitiveness of actual solution due to high manufacturing cost of manifold assemblies coming from this process. After analysis of current operations, taking into account presumed production plan, the capacitive calculation of assembly line was done. Then alternative solutions were proposed based on above mentioned criterion, and from these the optimal variant was picked and developed. The assessment of resultant solution was done in the end.

The diploma thesis is focused on optimizing of the assembly line of automotive headlamps BMW F30 LCI LED in the HELLA AUTOTECHNIK NOVA, s.r.o. Mohelnice company. The main intention of this thesis is in her first part the analysis of current status of arrangement assembly line, material flow and assembly procedures. In the second part of my thesis are proposed possible options for optimization. And in the last part of thesis is then selected optimal solution that streamlines the entire assembly process, possibly reducing the number of workers on the line and all based on technical and economic evaluation.

Orientador: Fernando Augusto Silva Marins / Coorientador: Aneirson Francisco da Silva / Banca: Valério Antonio Pamplona Salomon / Banca: Leonardo Antonio Monteiro Pessôa / Resumo: Neste trabalho aplicou-se a Simulação a Eventos Discretos na área de Intra-logística de abastecimento de uma linha de montagem de chassis, de uma indústria multinacional, (na fase de try-out). Objetivou-se desenvolver uma ferramenta gerencial que possibilitasse a identificação, a priori, de possíveis gargalos na linha de montagem, que possam surgir quando da sua implementação em regime de produção. Como delimitação do trabalho, foram simuladas, como variáveis de entrada, apenas os tamanhos de lotes de peças que abastecem as estações do trabalho robotizadas de solda dos subconjuntos dos chassis, adotando-se os dados de uma linha de montagem similar já existente. No desenvolvimento da ferramenta gerencial foi utilizada uma técnica de modelagem dedicada a projetos de simulação e um software comercial de simulação, bem como foram aplicados testes estatísticos não paramétricos na validação do modelo de simulação. O modelo simulado mostrou capacidade de atendimento à linha de montagem com oportunidade de otimização e de melhor balanceamento de mão de obra, dando origem a sugestões de melhoria no processo / Abstract: In this work had been applied the Discrete Events Simulation technique in the Intralogistics area of supply of a chassis assembly line, of a multinational industry, (in the try-out phase). The objective was to develop a management tool that would allow the identification, at first, of possible bottlenecks on the assembly line, which may arise when it is implemented under a production regime. As a delimitation of the work, only the batch sizes of pieces that supply the robotized welding cells of the chassis subassemblies were simulated as input variables, using data from a similar existing assembly line. In the development of the management tool, a modeling technique dedicated to simulation projects and a commercial simulation software were used, as well as nonparametric statistical tests were applied in the validation of the simulation model. The simulated model showed the ability to service the assembly line with the opportunity for optimization and better balancing of labor, giving rise to suggestions for improvement in the process / Mestre

Orientador: Marcela Aparecida Guerreiro Machado / Coorientador: Bruno Chaves Franco / Banca: Antonio Wagner Forti / Banca: José Luz Contador / Resumo: A crescente variedade de produtos nos sistemas atuais de produção é um grande desafio para a logística interna de abastecimento de materiais numa linha de montagem final, o abastecimento logístico precisa estar em concordância com a programação de produção de forma a disponibilizar para montagem o material necessário, no momento certo e na quantidade correta. A linha de montagem objeto do estudo acompanha esta tendência. Nela são montados modelos variados de chassis. Desta forma, o objetivo geral da pesquisa é desenvolver um modelo de abastecimento para linha de montagem multiprodutos, onde o ponto principal do trabalho é a definição do conceito mais adequado de acordo com o tipo e quantidade do material a ser abastecido. Através de uma pesquisa-ação foi proposto um modelo de abastecimento de linha que demonstrou uma redução de aproximadamente 50% da área ocupada na borda de linha, em consequência da redução de materiais, e aumento de 3% da produtividade, em virtude das reduções das indisponibilidades e perdas por set-up de abastecimento / Abstract: The increasing variety of products in current production systems is a big challenge for internal logistics supply of materials to a final assembly line, the logistic supply must be in step with the production program, in order to provide the necessary material for assembly at the right time and in the correct quantities. The assembly line which is the object of this study follows the trend. On it, several models of chassis are assembled. Therefore, the general objective of this research is to develop a supply model for a multi-product assembly line, with the main focus of the work on determining the most suitable concept in terms of the type and amount of material to be supplied. Through research-action, a model to supply the line has been proposed, which demonstrated a reduction of approximately 50% of the area occupied alongside the line, due to the reduction in materials, and an increase of 3% in productivity, owing to the reductions in outages and losses during supply set-up / Mestre

Printed circuit boards used in most ordinary electrical devices are usually equipped through an assembly line. Pick and place machines as part of those lines require accurate detection of incorrectly picked components, and this is commonly performed via image analysis. The goal of this project is to investigate if we can achieve state-of-the-art performance in an industrial quality assurance task through the application of artificial neural networks. Experiments regarding different network architectures and data modifications are conducted to achieve precise image classification. Although the classification rates do not surpass or equal the rates of the existing vision-based detection system, there remains great potential in the deployment of a machine-learning-based algorithm into pick and place machines. / Tryckta kretskort som används i de flesta vanliga elektroniska produkter är vanligtvis monterade i monteringslinjer. Ytmonteringsmaskinerna i dessa monteringslinjer kräver exakt detektering av felaktigt plockade komponenter, vilket ofta genomförs med hjälp av bildanalys. Målet med detta projekt är att undersöka om vi kan uppnå framstående resultat i en industriell kvalitetssäkringsuppgift genom användandet av artificiella neuronnätverk. Experiment utförs med olika nätverksarkitekturer och datamodifikationer för att uppnå exakt bildklassificering.  Även om klassificeringsgraderna inte uppnår klassificeringsgraderna hos existerande synbaserade detekteringssystem, finns en stor potential för användandet av maskininlärningsbaserade algoritmer i ytmonteringsmaskiner.

In recent years, customers' life stylish and behaviour have been changed and their tendencies become more diverse than before. As well as, market researches show a growing trend of special demands in their inclination. Accordingly, the companies compete to meet market demands for the reason of satisfying and maintaining the loyalty of their customers. This has led researchers to seek flexible methods and optimum solutions in production processes. In this regard, the manufacturing flow is one of the places in which flexibility and optimization can cause improvement is the assembly line. So, to meet the increasing diversity of market demand, assembly line processes must have the flexibility and ability to dynamically change product specifications and features while minimizing the operating and production processes' costs. For this reason, companies use solutions for designing assembly lines based on designing a flexible manufacturing system (FMS) for fast and better managing material feeding and handling. The FMS is a manufacturing method that is developed to easily can compatible with changes in production in the type and quantity of the product that has been manufactured. The performance of an FMS depends on the precise and efficient scheduling of material handling equipment. In this regard, the use of automated guided vehicles (AGV) instead of conveyors in an assembly line provid effectiveness and transformative.The aim of this research is to obtain the optimal numbers of AGVs required for the purpose of material handling at assembly lines. To solve the problem, a mathematical model has been developed. The objective function of the model is the number of AGVs. Accordingly, a set of variables and constraints have been determined have been considered to solve the linear optimization equation. In addition, the influence of workstations’ buffer capacity on material handling activities and the number of AGVs are studied by using this developed mathematical model.In order to evaluate experiments and analysis of the problem, Python programming software and its libraries have been used to calculate rapidly and accurately equations of the model. Preliminary results show that according to the layout of the production line and demand/production planning, as well as determining the size of input and output buffers of workstations, the proposed mathematical model calculates the minimum number of required vehicles and by changing the size of buffers we achieve different results. The aforementioned IT artefact is implemented in the direction of industrial digitalization and can be developed as application software in the eventuality. And further, this master project is desirable to take performance to continue sustainable development principles. / <p>Examensarbetet är på 16,5 hp:</p><p>Master Degree Project in Virtual Product RealizationOne year Level 16.5 ECTSSpring term 2022</p>

The efficiency of an assembly line depends on how the different tasks are distributed among the work stations that make up the assembly line. Assigning the tasks to the stations is called assembly line balancing (ALB) and is an NP-hard optimization problem. While automating line balancing has the potential to make manufacturing more efficient, and the problem has been studied for many decades, the research has not been widely adopted by industry, where planning is still largely done manually. This thesis discusses reasons for this theory-practice gap and suggests a direction that is more focused on real-world applications. This includes shifting the focus to a decision support system (DSS) rather than considering the ALB solver in isolation. Such a shift places the solver in a new context, where it plays a slightly different role and needs to fulfill slightly different requirements. A framework for building practical ALB solvers within a DSS context is proposed and then evaluated by implementing solvers for two different assembly line models. Increasingly refined versions of the ALB solvers are compared to each other, showing that the most specialized version performs substantially better than the simplest, which demonstrates that this framework allows an effective trade-off between development time and performance. One of the implemented solvers is also pitted against a state-of-the-art solver for the Simple Assembly Line Balancing Problem type 1 (SALBP-1) by comparing its results on a standard set of problem instances against the best published results. The comparison shows that the implemented solver is not just competitive but in some ways superior. On the largest instances, it produces improved solutions for 99 % of the instances that had not already been solved optimally, reducing the number of stations by more than 2 % on average. The solvers also demonstrated the potential to effectively trade off running time and solution quality, which is an important feature in an interactive system that is meant to support an iterative refinement process.

The thesis addresses the mixed model assembly line sequencing and outbound logistics planning problems in the automotive industry at the operational level. Different from the sequential decision-making procedure used in practice, the thesis proposes a scheme that integrates production sequencing and logistics planning. Mixed integer programs are established for the production sequencing, logistics planning, and integrated problems. The integrated model cannot be solved by commercial solvers in a reasonable amount of time. After studying the optimality properties of the product mode, the thesis proposes a modified integrated model. The results of numerical experiments and simulations demonstrate the benefit of the integration by comparing the modified integrated model with two sequential schemes, the Production-First-Scheme and the Logistics-First-Scheme.

Development, operation, and testing of a heuristic line balancing program for a microcomputer are discussed. Tasks are grouped into work stations along an assembly line such that the number of work stations required is minimized. The model is built primarily using the Hoffman (1963) procedure with modifications described by Gehrlein and Patterson (1975). For purposes of comparison the Rank Positional Weight technique (Helgeson and Birnie, 1961) is also included in the model. Testing included thirty-seven different balances using problems from the literature. For each balance, both Rank Positional Weight and Hoffmann solutions were obtained in the forward and reverse directions. Four measures of performance were considered in this study. These measures of performance were: (1) the average percentage a balance is above the optimum solutions, in terms of number of stations; (2) time to obtain a balance; (3) the best solution in terms of the lowest number of stations and lowest standard deviation of the slack times; and (4) the largest value of minimum station slack time. Overall it was found that the Hoffmann procedure with a delay factor if 1.5 was best suited for the microcomputer application. Further work is recommended to find the optimum delay factor and apply the Modified Hoffmann procedure to solving line balancing problems where the cycle time is minimized given a set of work stations.

I denna studie görs en jämförelse av prefabricerade våtrumsmoduler gentemot platsbyggda våtrum ur ett ekonomiskt-, tids- och kvalitetsperspektiv. Detta arbete görs i samarbete med Gunnar Prefab AB där en undersökning görs baserat på 300 fiktiva våtrum. Det huvudsakliga målet med detta arbete är att ta fram en kostnadskalkyl, en tidsplan och de kvalitetsmässiga aspekterna för metoderna. Detta i syftet om att ge en vägledning vid beslutsfattande om produktionsmetod vid framställning av våtrum. Jämförelsen baseras på en egenframtagen mängdförteckning och våtrummen granskas under godtyckliga förutsättningar i nyproduktion. Undersökningen har begränsats till en leverantör och en planlösning. Först tas en teoretisk referensram fram som är grundförutsättningarna för arbetet. I denna del sker en genomgång för hur tillverkningen av ett våtrum går till för respektive metod och teorin bakom framställningen av en kostnadskalkyl. Slutligen redovisas det hur tidsplanen och hur de kvalitetsmässiga aspekterna tas fram. I nästa kapitel redovisas tillvägagångssättet för beräkning av de direkta- och gemensamma kostnaderna samt genomförandet av jämförelsen i tid och kvalité. Det visade sig vara svårt att göra en kostnadsjämförelse baserat på ett så pass stort projekt som 300 badrum då övrig litteratur i ämnet visade på olika siffror i kostnadsfrågan. I jämförelse vad gäller kvalitén granskades metodernas kvalité- och ledningssystemen samt för- och nackdelarna ur kvalitésynpunkt. Detta resulterade i att kvalitén för det prefabricerade modulerna var något högre då enheterna tillverkas i kontrollerade förhållanden. Den största skillnaden mellan dessa byggmetoder var byggtiden. För det prefabricerade våtrummet tog det 34 veckor att framställa och för det platsbyggda tog det 102 veckor. Slutsatsen av arbetet är att det prefabricerade våtrummet produktionstekniskt blir det billigare alternativet endast om omfattning av projektet är tillräckligt stort, dock kan det vara ett bättre val ur ett kvalité- och tidsperspektiv. En rekommendation vid val av denna metod är att entreprenören behöver vara delaktig i ett tidigt skede för att minska byggtid och kostnad. Vid projekt med flera olika typbadrum rekommenderas att kombinera den prefabricerade metoden med den platsbyggda, då moduler inte går att implementera för exempelvis mindre WC. På grund av det höga trycket på marknaden kan det vara svårt att få tag på material och arbetskraft vilket kan leda till konsekvenser för slutresultatet. Vid pressade tids- och kostnadsförhållanden så kan prefabricerade moduler vara att föredra då de framställs i fabrik med en löpandebandprincip. / The premise of this thesis is a comparison study of which prefabricated bathroom modules are compared to on-site built bathrooms from an economic, time and quality standpoint. This work is done in collaboration with Gunnar Prefab AB where a survey is carried out based on 300 fictitious bathrooms. The main objective of this work is to develop a cost estimate, a timeline and the quality aspects for each method. The purpose is to provide guidance when choosing what production method is the most optimal choice when producing bathrooms. The comparison is based on a self-made quantity list and the bathrooms are examined under arbitrary conditions in new production. The survey has also been limited to one contractor and one specific architectural plan. The thesis starts off with a theoretical reference framework which is considered as the foundation of this report. In this chapter, an explanation is carried out on how the production of a bathroom is constructed for each method and the theory behind the production of a cost estimate. Lastly, an explanation is given on how the timeline and the quality aspects are developed throughout the project. The following subheading presents the approach of calculating direct and common costs and the implementation of the comparison in time and quality. It proved difficulties to make a cost comparison based on a project as large as 300 bathrooms do to that literature in this subject showed different figures revolving the cost issue. The result of collected quotes and cost calculations gives a total of 17 533 544 kronor for the prefabricated bathroom modules and 18 290 691 kronor for the built on-site bathrooms. To compare the quality and its advantages, disadvantages and quality- and management systems were examined from a quality point of view. The results concluded that the quality of the prefabricated modules was slightly better due to the fact that they were manufactured under a controlled environment. The main difference between said construction methods was the construction time. For the prefabricated bathrooms it took 34 weeks to produce and for the built on-site bathroom it took 102 weeks. The conclusion of this thesis is that the prefabricated bathroom could be the cheaper option only if the project would be of a larger scale and could be a better choice from a time-saving perspective. One recommendation when selecting this method is that the contractor needs to be involved from an early stage in order to reduce construction time and lower the costs. For projects with several different type of bathrooms where they have different layouts, it is recommended to combine the prefabricated method with the built on-site, as modules can’t be implemented for plans with smaller WC. Due to the high pressure on the market, it can be difficult to obtain materials and labour, which can lead to consequences for the end result. In projects where time and cost is of essence, the prefabricated modules may be preferable when produced in a factory that runs by the assembly line principle.