To see the other types of publications on this topic, follow the link: Balancing of assembly-lines.
Dissertations / Theses on the topic 'Balancing of assembly-lines'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 20 dissertations / theses for your research on the topic 'Balancing of assembly-lines.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Mapfaira, Herbert. "Assembly line balancing using hybrid genetic algorithms." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268500.
Full text
2
Rattan, Amanpreet. "Balancing of Parallel U-Shaped Assembly Lines with Crossover Points." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/88031.
Full textAbstract:
This research introduces parallel U-shaped assembly lines with crossover points. Crossover points are connecting points between two parallel U-shaped lines making the lines interdependent. The assembly lines can be employed to manufacture a variety of products belonging to the same product family. This is achieved by utilizing the concepts of crossover points, multi-line stations, and regular stations. The binary programming formulation presented in this research can be employed for any scenario (e.g. task times, cycle times, and the number of tasks) in the configuration that includes a crossover point. The comparison of numerical problem solutions based on the proposed heuristic approach with the traditional approach highlights the possible reduction in the quantity of workers required. The conclusion from this research is that a wider variety of products can be manufactured at the same capital expense using parallel U-shaped assembly lines with crossover points, leading to a reduction in the total number of workers.M. S.
3
Lim, Yun Fong. "Some Generalizations of Bucket Brigade Assembly Lines." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6910.
Full textAbstract:
A fascinating feature of bucket brigade assembly lines is that work load on workers is balanced spontaneously as workers follow some simple rules in the assembly process. This self-organizing
property significantly reduces the management effort on an assembly line. We generalize this idea in several directions. These include an adapted bucket brigade protocol for complex assembly networks, a generalized model that permits chaotic behavior, and a more detailed model for a flow line in which jobs arrive arbitrarily in time and are introduced into the system at several points on the line.
4
Pantouvanos, John P. "A computerized methodology for balancing and sequencing mixed model stochastic assembly lines." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-07212009-040309/.
Full text
5
Bhoja, Sudeer. "Optimization of the Assignment of Printed Circuit Cards to Assembly Lines in Electronics Assembly." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/37006.
Full textAbstract:
The focus of this research is the line assignment problem in printed circuit card assembly systems. The line assignment problem involves the allocation of circuit card types to an appropriate assembly line among a set of assembly lines with the objective of reducing the total assembly time. These circuit cards are to be assembled in a manufacturing facility, capable of simultaneously producing a wide variety of printed circuit cards in different production volumes. A set of component types is required for each printed circuit card. The objective is to assign the circuit cards to the assembly line such that the total assembly time, which includes the setup time as well as the processing time required for all card types in a set, is minimized.
The focus of this research is to develop an algorithmic strategy for addressing this problem in electronics assembly. This problem involves considering several interrelated decision problems such as assigning printed circuit cards to assembly lines, grouping circuit cards into families to reduce the number of setups, and assigning component types to machines to balance workload. The line assignment models are formulated as large scale mixed integer programming problems and are solved using a branch-and-bound algorithm, supplemented by techniques for improving the solution time. The models and solution approaches are demonstrated using industry representative data sets and can serve as useful decision support tools for process planning engineers.
Master of Science
6
Barutcuoglu, Sirin. "Flexible Assembly Line Design Problem With Fixed Number Of Workstations." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610697/index.pdf.
Full textAbstract:
ABSTRACT
FLEXIBLE ASSEMBLY LINE DESIGN PROBLEM WITH FIXED NUMBER OF WORKSTATIONS
Barutçuoglu, Sirin M.S. Department of Industrial Engineering Supervisor: Prof. Dr. Meral Azizoglu July 2009, 70 pages In this thesis, we study a Flexible Assembly Line Design problem. We assume the task times and equipment costs are correlated in the sense that for all tasks the cheaper equipment gives no smaller task time. Given the cycle time and number of workstations we aim to find the assignment of tasks and equipments to the workstations that minimizes the total equipment cost. We study a special case of the problem with identical task times. For the general case, we develop a branch and bound algorithm that uses powerful lower bounds and reduction mechanisms. We test the performance of our branch and bound algorithm on randomly generated test problems. The results of our experiments have revealed that we are able to solve large-sized problem instances in reasonable times.
7
Abdous, Mohammed Amine. "Optimal design of manufacturing systems with ergonomics : application to assembly lines." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEM034.
Full textAbstract:
Cette thèse contribue à l'évaluation et l'optimisation de l'ergonomie dans la phase de conception des systèmes de production. Une mauvaise ergonomie physique dans les systèmes de production se traduit par une productivité plus faible et des blessures des opérateurs, et augmente les coûts pour les entreprises. L'objectif principal de ce travail est de proposer des méthodes d'optimisation pour la conception de systèmes de production, tenant compte à la fois de l'ergonomie, de la productivité et des coûts. Ce travail se concentre sur la conception préliminaire des lignes d'assemblage. L'enjeu est de fournir aux décideurs des méthodes d'optimisation pour la prise en compte de l'ergonomie, tout en satisfaisant toutes les contraintes technologiques et économiques. Les problèmes combinatoires considérés sont les problèmes d'équilibrage de lignes d'assemblage et de sélection des équipements. Nous avons considéré un modèle quantitatif d'ergonomie basé sur des équations de fatigue et de récupération tirées de la littérature. Nous avons proposé une linéarisation permettant de définir un programme linéaire en variables entières pour ce problème et des méthodes de résolution optimale et approchée. Nous avons également proposé une généralisation de l'approche, avec un modèle multi-objectif optimisant le coût et l'ergonomie. Nous avons développé un algorithme multi-objectif pour sa résolution. Sur la base des modèles et des algorithmes d'optimisation proposés, nous avons défini une méthodologie pour la conception de lignes d'assemblage avec l'optimisation de l'ergonomie dès la phase de conception. Cette méthodologie a été appliquée avec succès dans deux cas industrielsThis thesis contributes to the research stream of evaluation and optimization of ergonomics in the design phase of manufacturing systems. Poor physical ergonomics in manufacturing systems results in lower productivity, lower motivation, injuries, and increases costs for companies. The main objective of this work is the proposition of optimization methods for manufacturing systems design, with the joint consideration of ergonomics, productivity, and cost. This work focuses on the preliminary design of assembly lines. The challenge is to provide decision-makers with optimization methods to take ergonomics into account while satisfying all technological and economic constraints. The combinatorial problems considered are the assembly line balancing problem and the selection of equipment. We considered a quantitative model of ergonomics based on fatigue and recovery equations taken from the literature. In addition to the combinatorial nature of problems dealt with, the main scientific challenge stems from the non-linear nature of the ergonomics model. We proposed a linearization allowing defining an integer linear program, we developed optimal and approximate resolution approaches. Besides, we proposed a generalization of the approach, with a multi-objective model optimizing cost and ergonomics. We developed a multi-objective algorithm for its resolution.Based on the proposed models and optimization algorithms, we have defined a methodology for the design of assembly lines with the optimization of ergonomics from the design phase. This methodology has been successfully applied to industrial cases
8
Kucukkoc, Ibrahim. "Modelling and solving mixed-model parallel two-sided assembly line problems." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/18917.
Full textAbstract:
The global competitive environment and the growing demand for personalised products have increased the interest of companies in producing similar product models on the same assembly line. Companies are forced to make significant structural changes to rapidly respond to diversified demands and convert their existing single-model lines into mixed-model lines in order to avoid unnecessary new line construction cost for each new product model. Mixed-model assembly lines play a key role in increasing productivity without compromising quality for manufacturing enterprises. The literature is extensive on assembling small-sized products in an intermixed sequence and assembling large-sized products in large volumes on single-model lines. However, a mixed-model parallel two-sided line system, where two or more similar products or similar models of a large-sized product are assembled on each of the parallel two-sided lines in an intermixed sequence, has not been of interest to academia so far. Moreover, taking model sequencing problem into consideration on a mixed-model parallel two-sided line system is a novel research topic in this domain. Within this context, the problem of simultaneous balancing and sequencing of mixed-model parallel two-sided lines is defined and described using illustrative examples for the first time in the literature. The mathematical model of the problem is also developed to exhibit the main characteristics of the problem and to explore the logic underlying the algorithms developed. The benefits of utilising multi-line stations between two adjacent lines are discussed and numerical examples are provided. An agent-based ant colony optimisation algorithm (called ABACO) is developed to obtain a generic solution that conforms to any model sequence and it is enhanced step-by-step to increase the quality of the solutions obtained. Then, the algorithm is modified with the integration of a model sequencing procedure (where the modified version is called ABACO/S) to balance lines by tracking the product model changes on each workstation in a complex production environment where each of the parallel lines may a have different cycle time. Finally, a genetic algorithm based model sequencing mechanism is integrated to the algorithm to increase the robustness of the obtained solutions. Computational tests are performed using test cases to observe the performances of the developed algorithms. Statistical tests are conducted through obtained results and test results establish that balancing mixed-model parallel two-sided lines together has a significant effect on the sought performance measures (a weighted summation of line length and the number of workstations) in comparison with balancing those lines separately. Another important finding of the research is that considering model sequencing problem along with the line balancing problem helps algorithm find better line balances with better performance measures. The results also indicate that the developed ABACO and ABACO/S algorithms outperform other test heuristics commonly used in the literature in solving various line balancing problems; and integrating a genetic algorithm based model sequencing mechanism into ABACO/S helps the algorithm find better solutions with less amount of computational effort.
9
Malyutin, Sergey. "Algorithms and Software for Decision Support in Design of Assembly and Transfer Lines." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEM020/document.
Full textAbstract:
Une vue d'ensemble des problèmes et des méthodes pour la conception des lignesd'assemblage et d'usinage est donnée. Un nouveau problème d'affectation de la main-d’œuvrepour une ligne d'assemblage multi-produit cadencée avec un objectif de minimiser lenombre d'opérateurs est étudié. Diverses relations de priorité entre les opérations et lesdifférentes fonctions définissant les temps d'opérations, en fonction du nombre d'opérateurssont considérés. Un nouveau problème d'optimisation multiobjectif pour une ligne d'usinagemono-produit est formulé. Plusieurs méthodes exactes et heuristiques et leursimplémentations informatiques pour les deux problèmes sont développées par l'auteur. Unmodule logiciel d'aide à la décision pour résoudre ces problèmes est développé et implémentédans un environnement d'un nouveau PLM d'IBM dans le cadre du projet européen amePLM.Ce module est testé sur un exemple réel de conception d'une ligne de montage des moteurschez Mercedes Benz en AllemagneAn overview of existing problems and methods for the design of assembly and transfer lines is given. A new workforce assignment problem for a paced multi-product assembly line with a goal of minimizing the number of workers is studied. Various precedence relations between operations and functions of operation processing times dependent on the number of workers areconsidered. A new problem of multi-objective optimization for a single product transfer line is solved. Several exact and heuristic methods and their computer implementations for both problems are developed by the author. An application of developed approaches to solving a real production problem relevant to the European project amePLM is demonstrated
10
López, De La Cova Trujillo Miguel Angel, and Niklas Bertilsson. "Investigation of the workforce effect of an assembly line using multi-objective optimization." Thesis, Högskolan i Skövde, Institutionen för ingenjörsvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-13134.
Full textAbstract:
ABSTRACT The aim of industrial production changed from mass production at the beginning of the 20th century. Today, production flexibility determines manufacturing companies' course of action. In this sense, Volvo Group Trucks Operations is interested in meeting customer demand in their assembly lines by adjusting manpower. Thus, this investigation attempts to analyze the effect of manning on the main final assembly line for thirteen-liter heavy-duty diesel engines at Volvo Group Trucks Operations in Skövde by means of discrete-event simulation. This project presents a simulation model that simulates the assembly line. With the purpose of building the model data were required. One the one hand, qualitative data were collected to improve the knowledge in the fields related to the project topic, as well as to solve the lack of information in certain points of the project. On the other hand, simulation model programming requires quantitative data. Once the model was completed, simulation results were obtained through simulation-based optimization. This optimization process tested 50,000 different workforce scenarios to find the most efficient solutions for three different sequences. Among all results, the most interesting one for Volvo is the one which render 80% of today’s throughput with the minimum number of workers. Consequently, as a case study, a bottleneck analysis and worker performance analysis was performed for this scenario. Finally, a flexible and fully functional model that delivers the desired results was developed. These results provide a comparison among different manning scenarios considering throughput as main measurement of the main final assembly line performance. After analyzing the results, system output behavior was revealed. This behavior allows predicting optimal system output for a given number of operators.
11
Abdelmageed, Mohamed Elnourani, and Filip Skärin. "Developing a line balancing tool for reconfigurable manufacturing systems : A tool to support investment decisions." Thesis, Jönköping University, JTH, Produktionsutveckling, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-52434.
Full textAbstract:
Purpose - This thesis aims to developing a decision-making tool which fits in a reconfigurable manufacturing system (RMS) milieu used to identify whether to introduce and produce a new product into an already existing assembly line or to invest in a new assembly line. To fulfil the purpose, four research questions were developed. Which line balancing problem-solving techniques exist in the literature? Which investment costs can be considered vital for new assembly lines as a consequence from new product introductions? Can a decision-making tool be designed to evaluate new product introductions which considers both line balancing KPIs and investment costs in an assembly line? To what extent can criteria in the RMS theory be linked with the attributes of the designed decision-making tool to support its applicability? Method - Literature studies were performed in order to create a theoretical foundation for the thesis to stand upon, hence enabling the possibility to answer the research questions. The literature studies were structured to focus on selected topics, including reconfigurable manufacturing systems, line balancing, and assembly line investment costs. To answer the third research question, which involved creating a decision-making tool, a single-case study was carried out. The company chosen was within the automotive industry. Data was collected through interviews, document studies and a focus group. Findings & analysis - An investigation regarding which line balancing solving-techniques suit RMS and which assembly line investment costs are critical when introducing new products has been made. The outputs from these investigations set the foundation for developing a decision-making tool which enables fact-based decisions. To test the decision-making tool’s compatibility with reconfigurable manufacturing systems, an evaluation against established characteristics was performed. The evaluation identified two reconfigurable manufacturing system characteristic as having a direct correlation to the decision-making tool. These characteristics regarded scalability and convertibility. Conclusions - The industrial contribution of the thesis was a decision-making tool that enables fact-based decisions regarding whether to introduce a new product into an already existing assembly line or invest in a new assembly line. The academic contribution involved that the procedure for evaluating the tool was recognized as also being suitable for testing the reconfigurable correlation with other production development tools. Another contribution regards bridging the knowledge gaps of the classifications in line balancing-solving techniques and assembly line investment costs. Delimitations - One of the delimitations in the thesis involved solely focusing on developing and analysing a decision-making tool from an RMS perspective. Hence, other production systems were not in focus. Also, the thesis only covered the development of a decision-making tool for straight assembly lines, not U-shaped lines.
12
Oesterle, Jonathan. "Holistic approach to designing hybrid assembly lines A comparative study of Multi-Objective Algorithms for the Assembly Line Balancing and Equipment Selection Problem under consideration of Product Design Alternatives Evaluation of the influence of dominance rules for the assembly line design problem under consideration of product design alternatives Hybrid Multi-objective Optimization Method for Solving Simultaneously the line Balancing, Equipment and Buffer Sizing Problems for Hybrid Assembly Systems Comparison of Multiobjective Algorithms for the Assembly Line Balancing Design Problem Efficient multi-objective optimization method for the mixed-model-line assembly line design problem Detaillierungsgrad von Simulationsmodellen Rechnergestützte Austaktung einer Mixed-Model Line. Der Weg zur optimalen Austaktung." Thesis, Troyes, 2017. http://www.theses.fr/2017TROY0012.
Full textAbstract:
Le travail présenté dans cette thèse concerne la formulation et la résolution de deux problèmes d'optimisation multi-objectifs. Ces problèmes de décision, liés à une approche holistique, ont pour but de sélectionner la meilleure configuration « produit/ligne d’assemblage » à partir d'un ensemble de design produits, et de ressources. Concernant le premier problème, un modèle de coût a été développé afin de traduire les interdépendances complexes entre la sélection d’un design produit et les caractéristiques des ressources. Une étude empirique est proposée et vise à comparer, selon plusieurs indicateurs de qualité multi-objectifs, différentes méthodes de résolution - comprenant des algorithmes génétiques, de colonies de fourmis, d’optimisation par essaims particulaires, des chauves-souris, de recherche du coucou et de pollinisation des fleurs. Plusieurs règles de dominance et une recherche locale spécifique au problème ont été appliquées aux méthodes de résolution les plus prometteuses. Concernant le second problème, qui se penche également sur le dimensionnement des stocks tampons, les méthodes de résolution sont à un modèle de simulation à événements discrets, dont la fonction première est l’évaluation des valeurs des différentes fonctions objectives. L’approche holistique associée aux deux problèmes a été validée avec deux cas industrielsThe work presented in this thesis concerns the formulation and the resolution of two holistic multi-objective optimization problems associated with the selection of the best product and hybrid assembly line configuration out of a set of products, processes and resources alternatives. Regarding the first problem, a cost model was developed in order to translate the complex interdependencies between the selection of specific product designs, processes and resources characteristics. An empirical study is proposed, which aimed at comparing, according to several multi-objective quality indicators, various resolution methods – including variants of evolutionary algorithms, ant colony optimization, particle swarm optimization, bat algorithms, cuckoo search algorithms, and flower-pollination algorithms. Several dominance rules and a problem-specific local search were applied to the most promising resolution methods. Regarding the second problem, which also considers the buffer sizing, the developed algorithms were enhanced with a genetic discrete-event simulation model, whose primary function is to evaluate the value of the various objective functions. The demonstration of the associated resolution frameworks for both problems was validated through two industrial-cases
13
Kovalev, Sergey. "PROBLÈMES COMBINATOIRES EN CONFIGURATION DES LIGNES DE FABRICATION : ANALYSE DE COMPLEXITÉ ET OPTIMISATION." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2012. http://tel.archives-ouvertes.fr/tel-00849179.
Full textAbstract:
L'objectif de la thèse est de créer et développer de nouvelles méthodes de résolution efficaces des problèmes combinatoires en configuration des lignes de fabrication. Deux problèmes ont été particulièrement étudiés: le problème d'équilibrage et de choix d'équipement pour des lignes dédiées et le problème de minimisation des coûts de changements de séries pour des lignes multi-produits. Une solution du premier problème consiste en une affectation admissible des ressources à un nombre de stations à déterminer de sorte que le coût total soit minimal. Afin de résoudre ce problème, nous l'avons réduit au problème de partition d'ensemble et l'avons résolu par des heuristiques gloutonnes et une méthode exacte de génération de contraintes. Les expérimentations sur différentes instances ont montré que la nouvelle approche de résolution surclasse les approches antérieures de la littérature en termes de qualité de solution et de temps de calcul. Pour le second problème deux critères sont considérés lexicographiquement : la minimisation du nombre de stations et la minimisation du coût de changement de séries. Nous avons examiné successivement les cas d'exécution parallèle et séquentielle des opérations. Des solutions approchées ont été trouvées par des heuristiques gloutonnes. Ensuite, nous avons proposé deux modèles de programmation linéaire en nombres entiers (PLNE) afin de trouver le nombre de stations minimal et ensuite d'obtenir le coût de changement de séries minimal. Les résultats des expérimentations sur ces nouveaux problèmes se sont avérés prometteurs à la fois en termes de qualité de solution et de temps de calcul.
14
Fagundes, Renato Alexandre. "Implementação de um processo cadenciador na fabricação de circuitos impressos rigidos." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265675.
Full textAbstract:
Orientador: Antonio BatocchioDissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-11T07:20:48Z (GMT). No. of bitstreams: 1 Fagundes_RenatoAlexandre_M.pdf: 1173048 bytes, checksum: f9c42d8865a1d2718c308d673b82bd20 (MD5) Previous issue date: 2007
Resumo: Este trabalho tem como objetivo a implementação de um processo cadenciador (ou puxador) na linha de produção de uma indústria fabricante de placas de circuito impresso rígidas, focando principalmente na implantação de um sistema cadenciador para que o fluxo de produção flua de uma maneira cadenciada e limpa para atender uma determinada família de produtos de placas de circuito impresso rígido (não metalizadas ¿simples face¿ e metalizadas ¿dupla face¿). A montagem da célula de produção para o estudo foi desenvolvida a partir da análise da técnica de mapeamento de fluxo estendido para se obter a melhor produtividade do sistema e atender as demandas do cliente final. A existência de algumas formas de variabilidades nos tempos takt, balanceamento de operadores, tempo para troca de modelos e dimensionamento do ciclo de máquinas foram estudadas e apresentadas buscando sempre uma otimização do fluxo contínuo dentro do processo cadenciador. Através das técnicas de mapeamento de fluxo de valor foi montado um mapa de estado atual e futuro o qual nos permite visualizar de uma maneira mais clara as correções propostas. Palavras chaves: Manufatura enxuta, Mapeamento de Fluxo de Valor, Tempo Takt, OBC
Abstract: This work has as objective the implementation of a pacemaker process in the line of production of an industry manufacturer of rigid printed circuit board, where the major is on the implantation of a pacemaker process allowing a production flow clean and smoth for one definitive product family of the printed circuit board (not metallized "single face" and metallized "double face"). The assembly of the cell of production for the study was developed from the analysis of the technique of Mapping Stream Value to get the best productivity of the system and to take care of the demands of the final customer. The existence of some forms of variabilities like : takt time, balancing of operators, time for exchange of models and sizing of the cycle of machines had been studied and presented searching always an optimization of the continuous flow inside of the pacemaker process. Through the techniques of Mapping Stream Value from the current state to future state was mounted which in allows them to visualize in a clear way of the corrections proposals. Key words- Lean Manufacturing, Value Stream Mapping, Takt Time, OBC
Mestrado
Planejamento e Gestão Estrategica da Manufatura
Mestre em Engenharia Mecânica
15
Lopes, Thiago Cantos. "Balancing optimization of robotic welding lines: model and case study." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2621.
Full textAbstract:
FA; UTFPR; RENAULTLinhas robóticas de solda são comuns na indústria automobilística. Durante a produção de um veículo, sua estrutura metálica precisa ser soldada em um único corpo resistente. Isso é feito por meio de centenas de soldas a ponto por resistência, cada uma liga localmente duas ou mais placas metálicas. Distribuir eficientemente esses pontos entre robôs é particularmente desafiador, levando em conta que: cada robôs podem fazer acessar uma parte dos pontos de solda, há tempo de movimentação entre pontos e robôs podem colidir entre si se ocuparem o mesmo espaço físico ao mesmo tempo. Há muitas maneiras factíveis de distribuir pontos de solda. No entanto, cada uma gera um resultado econômico diferente: Se um robô soldar muitos pontos se tornará um gargalo e reduzirá a taxa média de produção.Obter o conjunto de decisões operacionais que gera o melhor desempenho é o objetivo de técnicas de otimização. Há uma ampla variedade de técnicas descritas na literatura de pesquisa operacional e ciência da computação: modelos matemáticos, algoritmos, heurísticas, meta-heurísticas, etc. No contexto industrial, tais técnicas foram adaptadas para diversas variantes de problemas práticos. No entanto, estas adaptações só podem resolver as variantes para as quais foram idealizadas. Se por um lado podem se traçar paralelos entre vários aspectos de linhas robóticas de solda e tais variantes, por outro o conjunto completo de características das linhas estudadas não é tratável por (ou convertível em) nenhuma delas. A presente dissertação desenvolve uma abordagem para otimizar tais linhas, baseada em um modelo de programação linear inteira mista desenvolvido para descrever o problema. Ela também apresenta um estudo de caso para discutir e ilustrar possíveis dificuldades de aplicação e como superá-las. O modelo apresentado foi aplicado a dados de uma linha robótica de solda da fábrica, composta por quarenta e dois robôs, quatro modelos de veículos e mais de setecentos pontos de solda por veículo. A média ponderada da redução em tempo de ciclo obtida pelo modelo foi de 17.5%. Variantes do modelo, concebidas para auxiliar trabalhos futuros, são apresentadas e discutidas.
Robotic welding manufacturing lines are production lines common in automobile industries. During a vehicle's production, the vehicle's metal structure must be welded in a single resistant body. This is made by hundreds of spot-welding points, each of which tie locally two or more metal plates. Efficiently distributing these welding points amongst robots is particularly challenging, taking in account that: not all robots can perform all weld points, robots must move their welding tools between weld points, and robots might interfere with one another if they use the same geometrical space. There are multiple feasible manners to distribute the welding points. However, each of these forms generates different economical results: If a robot performs too many points, it will become a line bottleneck and reduce average throughput. To find the set of operational decisions that yields the best output is the goal of optimization techniques. There are a wide variety of such techniques described in operations research and computer sciences literature: mathematical models, algorithms, heuristics, meta-heuristics, etc. In the industrial context, these techniques were adapted to related line balancing problems. However, these adaptations can only solve the specific variants they were designed to address. While parallels can be drawn between aspects of robotic welding lines and many of such variants, the full combined set of characteristics of the studied lines is not treatable by (or convertible to) any of them. This dissertation develops a framework to optimize such lines, based on mixed-integer linear programing model developed to describe the problem. It also presents a case study to discuss and illustrate possible difficulties and how to overcome them. The presented model was applied to data from the factory's robotic welding lines composed of forty-two robots (divided in thirteen stations), four vehicle models and over seven hundred welding points for each vehicle. The weighted average reduction percentage in cycle time obtained by the model was 17.5%. Model variants, designed to aid further works are presented and discussed.
16
Wei-Juan, Gu, and 顧維鈞. "Construction and Comparison of Multi-model and Mixed-model Assembly Lines Balancing Problem." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/11948105522424084925.
Full textAbstract:
碩士國立勤益科技大學
工業工程與管理系
102
This research constructs two mathematical programming models, models 1 and 2, to solve multi-model and mixed-model assembly line balancing problem with the objective of total cycle time minimized. In this research, the case in Bedworth and Bailey (1982) and the case in Thomopoulous (1970) are chosen as the basis for the comparison of these two models. The computational result shows that model 2 is significantly superior to model 1. Furthermore, the objective of model 1 is modified to two objectives, the first objective is the maximum cycle time of each product is minimized and sum of the cycle time of all product is minimized is the second objective. The results show that the two objectives are with an irreconcilable conflict and the production manager must make trade-off between them.
17
Lu, Yu-Chi, and 呂祐騏. "Applying Genetic Algorithm to the Assembly Line Balancing Problemof Sewing Lines in Footwear Manufacturing Industry." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/90907865008552668793.
Full textAbstract:
碩士中原大學
工業工程研究所
95
Footwear manufacturing is a labor intensive industry. Due to intense global competition and declining profit margins, most footwear manufacturers need to improve productivity with better planning. The most critical process is sewing, as it generally involves a great number of operations processed by tens of operators. There exists precedence relationship among operations, and different operations require different sewing equipment. These characteristics increase the difficulty of line balancing in footwear manufacturing industry. This thesis develops a heuristic algorithm for assembly line balancing problem of sewing lines in footwear industry. The algorithm first uses Genetic Algorithm to determine the number of workstations based on the cycle time satisfying customer demands. It then uses Grouping Genetic Algorithm to balance the workload at different workstations. Real data from footwear manufacturers and experimental design are used to verify the performance of the proposed algorithm. Production managers can use the research results to quickly design sewing lines for important targets such as short cycle time and high labour utilization.
18
Κουτρούλη, Ευτυχία. "Το πρόβλημα της εξισορρόπησης γραμμών συναρμολόγησης στο τραπεζικό περιβάλλον." Thesis, 2012. http://hdl.handle.net/10889/6108.
Full textAbstract:
Στην παρούσα διπλωματική εργασία εξετάζουμε το θεωρητικό και το εμπειρικό υπόβαθρο των Προβλημάτων Εξισορρόπησης Γραμμών Συναρμολόγησης, την υποδειγματοποίηση τους και τις εφαρμογές τους. Αναλύουμε λεπτομερώς τις βασικές διαδικασίες επίλυσης των άνωθεν προβλημάτων όπως αυτές προτείνονται στη διεθνή βιβλιογραφία. Επιπρόσθετα, εξετάζουμε τις εφαρμογές των Γραμμών Συναρμολόγησης στην παραγωγή προϊόντων και υπηρεσιών. Ειδικότερα, μελετάμε την Εξισορρόπηση των Γραμμών Συναρμολόγησης στον τομέα των υπηρεσιών με εμπειρική εφαρμογή στα τραπεζικά δάνεια. Στόχος της διπλωματικής εργασίας είναι η παρουσίαση του τρόπου με τον οποίο ένα κλασσικό ζήτημα βιομηχανικής παραγωγής όπως είναι το πρόβλημα της εξισορρόπησης γραμμών συναρμολόγησης (που συναντιέται κύρια σε βιομηχανίες μαζικής παραγωγής τυποποιημένων προϊόντων όπως η αυτοκινητοβιομηχανία) εφαρμόζεται και στον τομέα των υπηρεσιών. Την λεπτομερή καταγραφή των σταδίων που συνδέονται με την παραγωγή τραπεζικών προϊόντων όπως είναι τα δάνεια, ακολουθεί σχετική μελέτη περίπτωσης. Η μελέτη αυτή χωρίζεται σε δύο βασικές περιπτώσεις. Με τη χρήση μιας σειράς μεθόδων οδηγούμαστε στην επίλυση του προβλήματος που διατυπώνουμε. Αναζητούμε την άριστη κατανομή των παραγωγικών συντελεστών για την επίτευξη του επιθυμητού αποτελέσματος. Πιο συγκεκριμένα, ο στόχος της εμπειρικής προσέγγισης είναι ο εντοπισμός του βέλτιστου αριθμού των αναγκαίων υπαλλήλων που πρέπει να ασχοληθούν με τις εργασίες δανειοδότησης λαμβάνοντας υπόψη τους περιορισμούς προήγησης στην ανάθεση των διαφόρων εργασιών.-
19
Lin, Yi-Jhen, and 林宜蓁. "A Study of Resource-Constrained Assembly Line and Worker Assignment Balancing Problem for Sewing Lines in Apparel Industry." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/26551495428051873384.
Full textAbstract:
碩士國立清華大學
工業工程與工程管理學系
102
Apparel manufacturing is a operator-intensive traditional industry helping the economy growth in Taiwan. The most critical manufacturing process is sewing, as it generally involves a great number of manual operations. A balanced sewing line can reduce operator requirement, increase production efficiency, decrease operator cost, and reduce production cycle time. This paper uses Grouping Genetic Algorithm (GGA) to solve types I and II Resource-Constrained Assembly Line and Worker Assignment Balancing Problem (RCALWABP) in sewing lines of apparel industry. Type I RCALWABP in sewing lines was solved using GGA to minimize the number of workstations for a given cycle time. Type II RCALWABP was solved using GGA to minimize the cycle time and maximize the throughput for a given number of workstations. Type II RCALWABP is generally considered as the extension of Type I RCALWABP. The solution of types I and II RCALWABP in sewing lines has high practical value, but there is only limited literature in this area. This paper takes into account several practical characteristics in apparel industry, including multi-skill operators, operator efficiency, and learning curve. Real data from apparel factories will be used to set the best parameters of GGA and evaluate GGA’s performance based on experimental design.
20
Gonçalves, Ana Sofia Jesus. "An assessment of the mixed-model assembly line balancing and sequencing problem." Master's thesis, 2020. http://hdl.handle.net/10316/92134.
Full textAbstract:
Dissertação de Mestrado em Engenharia e Gestão Industrial apresentada à Faculdade de Ciências e TecnologiaA manufatura evoluiu e com a sua evolução surgem novos desafios que se pretendem superar. A produção em massa foi substituída pela customização em massa, o que obrigou as empresas a reformular as linhas de montagem. O crescimento da procura por produtos customizados obrigaria a custos avultados na construção de uma linha para cada variante dos produtos. Assim, surgiram as linhas de montagem de modelos mistos, e o tradicional layout reto foi substituído pelo formato em U para obter maior flexibilidade. Com estas apareceram também novos problemas relacionados com a equilibragem das linhas e o seu sequenciamento. Este trabalho centra-se no sequenciamento destas novas linhas de montagem, mas para tal é necessário garantir que existe uma equilibragem teoricamente perfeita da linha. Para uma linha que monta cilindros pneumáticos e com uma possibilidade de gerar mais de 200 combinações distintas, a sua equilibragem e o seu sequenciamento são tarefas árduas e complexas. Através da simulação e da análise dos dados fornecidos pela simulação, espera-se obter as informações necessárias. As informações sobre as listas de combinações dos produtos que devem ser evitadas no sequenciamento são recolhidas para que não ocorram paragens não planeadas pela equilibragem. Ao serem eliminadas estas listas de maior percentagem de bloqueamento espera-se alcançar o sequenciamento ideal. Este método foi facilmente testado e verificado para uma linha perfeitamente equilibrada de três estações e dois produtos. Ao aumentar a complexidade de forma a aproximar-se da linha real, o número de sequencias que causam o bloqueio da linha aumentam de forma exponencial. Minimizar o tempo bloqueado será cada vez mais crucial para a empresa, mas outras regras podem ser violadas. Definir claramente o peso da transgressão das regras estipuladas permitirá entender o impacto de desconsiderar as quantidades de produção para minimizar o tempo ocioso.
Manufacturing has evolved, and with its evolution, new challenges arise that are intended to be overcome. Mass production was replaced by mass customization, which forced companies to reformulate the assembly lines. The growth of demand for customized products meant high costs in the construction of a line for each product variant. Thus, the mixed-model assembly lines emerged, and the traditional straight layout was replaced for the U-shaped form to obtain greater flexibility. New problems related to the balance of the lines and their sequencing have arisen. This work focuses on the sequencing of these new assembly lines, but for this, it is necessary to ensure that there is a theoretically perfect balance of the line. For an assembly line that assembles pneumatic cylinders and with the possibility of generating more than 200 different combinations, its balance and sequencing are arduous and complex tasks. Through the simulation and analysis of the data provided by the simulation, it is expected to obtain necessary information. Information about lists of product combinations that should be avoided in the sequencing is collected so as not to occur unplanned stops in the balancing. When the lists of products with the highest blocking percentage are eliminated, the ideal sequencing is expected to be achieved. This method was easily tested and verified for a perfectly balanced line of three stations and two products. When increasing the complexity to approach to the real line, the number of lists that cause the line to block increases exponentially. To minimize the blocked time will be increasingly crucial for the company, but other rules can be broken. Clearly defining the weight of breaking the rules will allow understanding the impact of disregarding production quantities to minimize idle time.