During the past decades, there have been an acceleration of customers’ needs of customized products. This have pressured many companies in offering customized products in order to reach customer satisfaction and keep growing and expanding their market share. Nowadays the competitive pressure between companies with the same product segment is increasing and the market requirements are changing rapidly. To handle this competition, many manufacturing companies are focusing on mass customized production. However, mass customization has been a topic of interest for many researchers. The focus has been in studying and understanding the complexity and the constrains that a company encounter when dealing with mass customized production in mostly the automotive industry. One of the constrains that have been less highlighted by researchers were the effects that mass customized production has on the output variation of production lines. Therefore, the purpose of this thesis is to investigate how to minimize output variations in mass customized production within assembly lines. To do that the researchers focused on studying the output variation in whitegoods industry instead of the automotive industry that captures most of the existing research. The study includes two main research questions. The first question was to identify the factors that affect the output variation in mass customized production. While the second question was to identify applicable solutions that can be used to stabilize the output. To ensure the reliability and validity of the research findings, the researchers used multiple case study combined with literature reviews. To answer the research questions several data collection techniques were used in the multiple case study conducted on two lines. Those data collection techniques were participating observations, document reviews, a semi-structured interview and many conversations with the affected persons. The findings from the case study for research question one showed consistency with the theories described in the theoretical background. This was evident because similar problems when it comes to output variations were defined in the theories. One problem was about the simplification of assembly line balancing problem that was evident in both case studies. This was an effect of the missing product family classification which created a high output variation because of the use of only one line balancing for all product variants. Another problem identified included functionality problems of machines because of performing wrong assembly or the use of the wrong component. There was as well the problem of missing or delayed components which was an effect of the lack of structure in the material picking and the deliveries performed for both lines. A combination of those factors created the experienced output variation on both lines. To deal with those problems and minimize the output variation, a solution approach was defined in the second research question. This approach was created together with the case company with the help of the theoretical background and it presents several steps to follow when attacking and resolving similar problems as presented above. The most important conclusion of this thesis is that, when dealing with output variation in mass customized production where people are performing the assembly, it is essential to provide the right conditions for them to ensure that they have the right knowledge base to perform the requested assembly.

Les humains et les robots travaillant en toute sécurité et en parfaite harmonie dans un environnement est l'un des objectifs futurs de la communauté robotique. Quand les humains et les robots peuvent travailler ensemble dans le même espace, toute une catégorie de tâches devient prête à l'automatisation, allant de la collaboration pour l'assemblage de pièces, à la manutention de pièces et de materiels ainsi qu'à leur livraison. Garantir la sûreté des humains nécessite que le robot puisse être capable de surveiller la zone de travail, déduire l'intention humaine, et être conscient suffisamment tôt des dangers potentiels afin de les éviter.Des normes existent sur la collaboration entre robots et humains, cependant elles se focalisent à limiter les distances d'approche et les forces de contact entre l'humain et le robot. Ces approches s'appuient sur des processus qui se basent uniquement sur la lecture des capteurs, et ne tiennent pas compte des états futurs ou des informations sur les tâches en question. Un outil clé pour la sécurité entre des robots et des humains travaillant dans un environnement inclut la reconnaissance de l'intention dans lequel le robot tente de comprendre l'intention d'un agent (l'humain) en reconnaissant tout ou partie des actions de l'agent pour l'aider à prévoir les actions futures de cet agent. La connaissance de ces actions futures permettra au robot de planifier sa contribution aux tâches que l'humain doit exécuter ou au minimum, à ne pas se mettre dans une position dangereuse.Dans cette thèse, nous présentons une approche qui est capable de déduire l'intention d'un agent grâce à la reconnaissance et à la représentation des informations de l'état. Cette approche est différente des nombreuses approches présentes dans la littérature qui se concentrent principalement sur la reconnaissance de l'activité (par opposition à la reconnaissance de l'état) et qui « devinent » des raisons pour expliquer les observations. Nous déduisons les relations détaillées de l'état à partir d'observations en utilisant Region Connection Calculus 8 (RCC-8) et ensuite nous déduisons les relations globales de l'état qui sont vraies à un moment donné. L'utilisation des informations sur l'état sert à apporter une contribution plus précise aux algorithmes de reconnaissance de l'intention et à générer des résultats qui sont equivalents, et dans certains cas, meilleurs qu'un être humain qui a accès aux mêmes informations. / Humans and robots working safely and seamlessly together in a cooperative environment is one of the future goals of the robotics community. When humans and robots can work together in the same space, a whole class of tasks becomes amenable to automation, ranging from collaborative assembly to parts and material handling to delivery. Proposed standards exist for collaborative human-robot safety, but they focus on limiting the approach distances and contact forces between the human and the robot. These standards focus on reactive processes based only on current sensor readings. They do not consider future states or task-relevant information. A key enabler for human-robot safety in cooperative environments involves the field of intention recognition, in which the robot attempts to understand the intention of an agent (the human) by recognizing some or all of their actions to help predict the human’s future actions.We present an approach to inferring the intention of an agent in the environment via the recognition and representation of state information. This approach to intention recognition is different than many ontology-based intention recognition approaches in the literature as they primarily focus on activity (as opposed to state) recognition and then use a form of abduction to provide explanations for observations. We infer detailed state relationships using observations based on Region Connection Calculus 8 (RCC-8) and then infer the overall state relationships that are true at a given time. Once a sequence of state relationships has been determined, we use a Bayesian approach to associate those states with likely overall intentions to determine the next possible action (and associated state) that is likely to occur. We compare the output of the Intention Recognition Algorithm to those of an experiment involving human subjects attempting to recognize the same intentions in a manufacturing kitting domain. The results show that the Intention Recognition Algorithm, in almost every case, performed as good, if not better, than a human performing the same activity.

The purpose of this thesis is to develop a model that is going to be used when wanting to cost-effectively improve the productivity of material supply to assembly with consideration to improve ergonomics and quality of semi-finished products. For this approach a case company’s material supply and assembly station have been studied. By utilising interviews, observations, time measurements and the company’s archival records relevant data have been gathered to review the company’s current materials supply method and assembly station in order to compare it with new possible materials supply methods. A cost break down structure was made in order to identify the different cost drivers for the different materials supply methods. This facilitated the time measurements since they pointed out which operations/activities that should be studied. There were two main types of materials supply methods used in the comparisons, which were line stocking and materials kitting. Line stocking was the first alternative since it was their current material supply method. In materials kitting, the new material supply method, there was two sub types examined, kit carriers and kits in pallets. The conclusion was that that the kit carriers made it possible to improve the labour productivity of one assembly station and at the same time being cost-effective. The kit carriers did also improve the ergonomics for the assembler, but on the contrary worsened the ergonomics for the material handlers. It was also perceived by the assemblers and materials handlers that the quality of the materials was improved when using the kit carriers. / Syftet med det här examensarbetet är att utveckla en modell som kommer att användas när man kostnadseffektivt vill förbättra produktiviteten av materialförsörjningen till montering med hänsyn till att förbättra ergonomin och kvaliteten på halvfabrikats produkter. För denna uppgift har ett fallföretags materialförsörjning och en monteringsstation blivit studerade. Genom att använda intervjuer, observationer, tidmätningar och företagsdokument så har relevant data samlats in for att undersöka företagets nuvarande materialförsörjningsmetod och monteringsstation för att kunna jämföra de mot nya möjliga materialförsörjningsmetoder. Ett kostnadsstrukturträd gjordes för att kunna identifiera de kostnadsdrivare för de olika materialförsörjningsmetoderna. Detta underlättade tidmätningarna eftersom de pekade ut vilka operationer/aktiviteter som borde bli studerade. Det var två huvudsakliga materialförsörjningsmetoder som användes i jämförelserna, vilka var linje lagring och kittning av material. Linje lagring var det första alternativet eftersom det var deras nuvarande materialförsörjningsmetod. I kittningen av material, som var det nya alternativet, så var det två subtyper undersökta, kitvagnar och kit i pall. Slutsatsen var att kitvagnarna gjorde det möjligt att förbättra arbetsproduktiviteten i en monteringsstation samtidigt som den var kostnadseffektiv. Kitvagnarna förbättrade även ergonomin för montören men däremot försämrade den ergonomin för materialhanterarna. Det upplevdes också av montörerna och materialhanterarna att kvalitén av materialen förbättrades när kitvagnarna användes.

Modern manufacturing systems seem to be shifting from mass production to mass customisation, which means that systems must be able to manage changes in customer demands and requirements, new technology as well as environmental demands. This in turn leads to an increase in product variants that need to be assembled. To handle this issue, well designed and presented information is vital for assembly workers to perform effective and accurate assembly tasks. In this thesis the main focus has been to find factors that affect human performance in manual assembly. A literature review was made on the subject of manufacturing and usability as well as basic cognitive abilities used to utilise information, such as memory. This investigation identified applicable factors for assessing human cognitive performance within the research field of manufacturing. The thesis further investigates how some of these factors are handled in manual assembly, using case studies as well as observational studies. The results show that how material and information are presented to the assembler needs to be considered in order to have a positive effect on the assembly operation. In addition, a full factorial experimental study was conducted to investigate different ways of presenting material and information at the workstation while using mixed assembly mode with product variants. The material presentation factor involved the use of a material rack compared to using an unstructured kit as well as a structured kit and the information presentation factor involved using a text and number instruction compared to a photograph instruction. The results showed that using a kit is favourable compared to the traditional material rack, especially when using a structured kit combined with photographic instruction. Furthermore, the use of unstructured kits can lead to better productivity and reduced perceived workload, compared to a material rack. Although they are perhaps not as good as using a structured kit, they most likely bring a lower cost, such as man-hour consumption and space requirements. However, the number of components in an unstructured kit needs to be considered in order to keep it on a manageable level. As a conclusion, several scenarios were developed in order to understand how different assembly settings can be used in order to improve human performance at the assembly workstation.

No description available.

Volvo CE at Hallsberg, Sweden is specialized in the production of cabs for construction equipment. The organization employs the one-line (mixed-model assembly) method, where cabs for different products are all assembled on the same main line. Operations on the main line are not standardized for all products. The future vision of the company is to establish the fishbone factory concept, where the diversity is introduced in sub-flows and variation is reduced on the main line.This is primarily to reduce balancing losses and eventually reduce the total throughput time of the plant. The thesis work focuses on a new product known as the Next Gen Cab. These cabs are designed to support the fishbone factory concept. Next Gen cabs comprise of physical modules that provide different customer features, but are designed with standard interference and toolpoints. They follow the common architecture approach. The aim of this thesis work is to develop an assembly setup for the production of the front module within the next gen cabs, and investigate a suitable material feeding technique. The work also focuses on the transition phase, which comprise of the production of both existing and Next Gen cabs. The methodology used for the work includes the understanding of the current state to determine possibilities of utilizing the existing setup. The report explains part and process similarities between the existing cabs and Next Gen cabs which aids in the development of an assembly setup through line balancing. Two material feeding concepts have been developed and a framework has been established for part presentation at Point-of-Use. It is followed by a comparison of the concepts based on factors such as kitting time, headcount cost, stock value and required investment. The concepts are evaluated and finally, a conclusion is made along with a recommendation on how the company can proceed when the new products are introduced. / Volvo CE i Hallsberg, Sverige är specialiserat på produktion av hytter för entreprenadmaskiner. Organisationen använder en enkellinje metod (blandad-modellmontering), där alla hytter för olika produkter monteras på samma huvudlinje. Operationerna på huvudlinjen är inte standardiserad för alla produkter. Framtidsvisionen för företaget är att etablera fiskbensfabrikskonceptet, där mångfalden införs i delflöden och variationen minskas påhuvudlinjen. Detta är främst för att minska balanseringsförlusterna och så småningom minska anläggningens totala genomströmningstid. Examensarbetet fokuserar på en ny produkt som kallas Next Gen Cab. Dessa hytter är utformade för att stödja fiskbensfabrikskonceptet. NextGen-hytterna består av fysiska moduler som ger olika kundfunktioner, men är utformade med standardkopplingar och verktygspunkter. De följer den gemensamma arkitekturstrategin. Syftet med detta examensarbete är att utveckla ett monteringsupplägg för framställning av frontmodulen inom next gen hytter, och undersöka lämplig materialmatningsteknik. Arbetet fokuserar också på övergångsfasen, som består av produktion av både befintliga och NextGen-hytter. Metoden som används för arbetet inkluderar förståelse för det aktuella tillståndet för att bestämma möjligheterna att använda den befintliga uppställningen. Rapporten förklarar likheter mellan delar och processer för de befintliga hytterna och Next Gen-hytterna vilket hjälper till att utveckla en monteringsuppställning genom linjebalansering. Två materialförsörjningskoncept har utvecklats och ett ramverk har skapats för delpresentation vid Point of-Use. Detta följs av en jämförelse av koncepten baserat på faktorer som ”kittnings”-tid, antal anställda, aktievärde och nödvändiga investeringar. Koncepten utvärderas och utmynnar i en slutsats tillsammans med en rekommendation om hur företaget kan gå vidare när de nya produkterna introduceras.

Bakgrund: Under de senaste decennierna har industriell logistik fått en allt viktigare roll för att ge företag konkurrensfördelar på den globala marknaden. För att uppnå ökad effektivitet i logistikfunktionen kan konfigurationen av ett internt materialförsörjningssystem ha en betydande inverkan på minimering av icke värdeadderande aktiviteter. Det finns flera principer för intern materialförsörjning, hur dessa appliceras har en signifikant påverkan i en industriell miljö. Valet mellan olika system kännetecknas av en överhängande komplexitet där tillverkningsindustrier byter fram och tillbaka flera gånger. Syfte: Syftet med studien är att föreslå ett ramverk för utveckling av interna materialförsörjningssystem gällande svetsprocess inom metallbearbetning. Genomförande: Studien är genomförd som en enfallsstudie på Hörle Automatic. Där studiens tillvägagångsätt har varit att identifiera icke värdeadderade aktiviteter i fallföretagets interna materialförsörjningssystem till svetsprocessen. För att därefter utveckla deras nuvarande system för att minimera identifierade aktiviteter. Utifrån detta har ett ramverk konstruerats som belyser faktor som ska tas i beaktning vid utveckling av ett internt materialförsörjningssystem. Empiriskt material har samlats in genom intervjuer, observationer, fokusgrupper och arkivmaterial. För att möjliggöra identifiering av icke värdeadderande aktiviteter har en processkartläggning upprättats. Fortsättningsvis har det genomförts tester gällande förslag på arbetssätt som utvecklats. Resultat/Diskussion: Ett ramverk har konstruerats som belyser elva olika faktorer som ska tas i beaktning vid utveckling av ett internt materialförsörjningsystem. Det är faktorer relaterade till produktionsvariation, detaljspecifikation, layout, leverantörer och kommunikation. Slutsats: Det har identifierats totalt 18 icke värdeadderande aktiviteter gällande Hörle Automatics interna materialförsörjningssystem till svetsprocessen. Utvecklingen av det interna materialförsörjningssystemet enligt förslag eliminerar en del icke värdeadderande aktiviteterna som identifierats. Resterande aktiviteter minskas genom utvecklingen av en materialförsörjningsprocess som möjliggör en ny layout och att mer kostnadseffektiv personal utför de icke värdeadderande aktiviteterna / Background: Over the past decades, industrial logistics has gained an increasingly important role in giving companies a competitive edge in the global market. To achieve increased efficiency in the logistics function, the configuration of an internal materials supply system may have a significant impact on minimizing non-value added activities. There are several principles for internal materials supply system, how these are applied have a great impact on it’s industrial environment. The choice between different systems is characterized by an complexity where manufacturing industries change back and forth several times. Purpose: The purpose of this study is to propose a framework for the development of internal materials supply systems in the welding process within metalworking. Methodology: This is a case study at Hörle Automatic. The study approach has been to identify non-value adding activities in the case company's internal materials supply system to the welding process. And after that develop their current system to minimize identified activities. Based on this, a framework has been designed to highlight the factors to be taken into account when developing an internal materials supply system. Empirical material has been collected through interviews, observations, focus groups and archival material. To enable identification of nonvalue-adding activities, a process mapping has been established. Furthermore, tests have been carried out regarding internal materials supply processes to strengthen the author's proposal. Result/Discussion: The result of the study is a framework including eleven factors that companies should take into account when developing an internal materials supply system. The framework involves factors regarding, production variation, item specification, layout, suppliers, and communication. Conclusion: A total of 18 non-value adding activities was identified regarding Hörle Automatic's internal materials supply system in their welding process. The development of the internal materials supply system as proposed eliminates some of the identified nonvalue-adding activities performed by welding operators. The remaining activities are reduced through a new layout and that usage of more cost-effective personnel.

Purpose - What influences the choice of material supply systems as well as how the design of the systems influences the efficiency of the assembly is substantially important. This because the target audience of the study; manufacturing companies whom applies any kind of material supply system, must be able to achieve and maintain a social and economic sustainability. Thus, the study aims to: Increase knowledge of how the choice and arrangement of material supply affects the efficiency of assembly. The purpose has been broken down into three research questions: 1.      Which is the most suitable material supply system depending on various types of factors? 2.     How does the material supply system affect the efficiency of the assembly process? 3.     How should material supply systems be adapted for an efficient assembly process? Method - The purpose of the study and the research questions are based on the problem description that was formulated. An abductive approach has characterized the case study work process. The literature review has formulated by a review of previous research and has together with the data collection methods: interviews, observations and document studies, formed the analysis. In order to provide answers to the study’s research questions, collected data was compared to previous research, in order to find similarities or differences. Result - The choice of material supply system is mainly influenced by applied production strategy, production system and the setup of the assembly. It doesn’t matter how the choice has been made unless a well-functioning information system exists, in terms of efficiency of the assembly. Walking distances as well as the location of components and how they are introduced to the assembler, should also be considered in the design of the material supply systems. That is important due to the value-adding activities performed at the assembly station. Several problems have been identified with the use of Lean tools which contributed to formulated improvement suggestions. Implications – The theoretical contributions of the study covers the inadequate theory that was found when connecting production strategies with the advantages and disadvanatges of material supply systems. Also, most of the theories emphasize how efficiency in assembly lines can be improved with the use of material supply systems, but there is limited information how the design of material supply systems affects the efficiency of assemblers in production cells. Empirically, the study contributes with different stages where various issues and wastes have been identified based on the presentation and the arrangement of the material supply systems. This increases the opportunity to prioritize the issues which should be based on the stages that includes most waste. Likewise, the choice of material supply system can be used as guidelines to find out when each system is most suitable. Limitations - Since data has been collected from only one company, the study's validity can be questioned. In addition, an abductive approach made the study complex as well as time-consuming and contributed to that the intended use of economic models was defaulted. / Syfte – Valet av materialförsörjningssystem påverkas i första hand av olika faktorer. Därtill är systemens utformning av betydelse för monteringens effektivitet. Detta för att studiens målgrupp; tillverkande företag där någon form av materialförsörjningssystem tillämpas ska kunna uppnå och bibehålla en social- samt ekonomisk hållbarhet. Därmed är studiens syfte att: Öka förståelsen för hur valet samt utformningen av materialförsörjningssystem påverkar effektiviteten i montering. Syftet har sedan brutits ned i tre frågeställningar: 1.      Vilket är det mest lämpade materialförsörjningssystemet beroende på olika          påverkansfaktorer? 2.     Hur påverkas materialförsörjningssystem monteringsprocessen effektivitet? 3.     Hur bör materialförsörjningssystem anpassas för en effektiv monteringsprocess? Metod – Studiens syfte samt frågeställningar är baserade på den problemformulering vilken definierades i enlighet med fallföretagets önskemål. En abduktiv ansats har präglat enfallsstudiens arbetsprocess. Litteraturöversikten har formats genom granskning av tidigare forskning och har tillsammans med datainsamlingsmetoderna: intervjuer, observationer samt dokumentstudier utgjort analysavsnittet. För att kunna ge svar på studiens frågeställningar jämfördes insamlad data med tidigare forskning, för att hitta likheter alternativt skillnader. Resultat – Valet av materialförsörjningssystem påverkas främst av respektive produktionsstrategi, produktionssystem samt produktionsupplägg. Det är oväsentligt sett till monteringens effektivitet, hur valet genomförts om inte ett välfungerande informationssystem existerar. Därtill bör hänsyn även tas till gångavstånd samt lokalisering av komponenter vid utformandet av materialförsörjningssystemens upplägg samt presentation. Detta då monteringens värdeskapande arbete ska kunna uppnå största möjliga effektivitet. Flertalet problem identifierades med hjälp av Lean-verktyg vilket möjliggjorde att förbättringsförslag lämnades. Implikationer – Studiens teoretiska bidrag behandlar kopplingen mellan applicerad produktionsstrategi samt materialförsörjningssystemens för- och nackdelar, vilket under studiens arbetsprocess visat sig vara bristfälligt. Likaså framhäver merparten av teorierna hur monteringens effektivitet påverkas i ett line-utformat produktionsupplägg, varav paralleller mellan grupporganiserat produktionsupplägg samt materialförsörjningssystem även utgör studiens teoretiska bidrag. Empiriskt sett bidrar studien med att materialförsörjningens presentation och upplägg delats upp i olika steg där diverse problem samt slösersier identifierats, vilket ökar möjligheterna kring att prioritera bland mest väsentliga problem. Prioriteringen bör utgå från steget, där flest slöserier återfinns. Likaså bidrar valet av materialförsörjningssystem med en guidning kring när respektive system är mest lämpligt att använda. Begränsningar – Då det insamlats data från endast ett företag kan studiens generaliserbarhet ifrågasättas. Dessutom innebar en abduktiv ansats att studien varit komplex samt tidskrävande och bidrog till att nyttjandet av tilltänkta ekonomiska modeller uteblev.