Considering that the current technology is constantly improving, it becomes increasingly important to have an efficient logistics in a company to maintain profitability while achieving a competitive business. Efficient logistics may be accomplished by improving the internal materials handling. In this thesis the internal material handling of steel frames has been studied at a factory in Vaggeryd. The goal of this study is to investigate the problems that exist with the current production flow of products and provide suggestions on how it can be developed to reduce unnecessary handling and movement. The study has a deductive approach where the authors has been using literature studies parallel with empirical analyzes conducted at a company to achieve the purpose of the study. Documentation from the company and interviews with staff and observations form the basis for the data collection carried out. Based on this choice of method, the authors have identified possible problems in the internal material handling at the company and by using well known theories they have accomplished a result. The authors present the improvement proposals in two different ways. The first, specific suggestions, involving problems caused by different rates of operation times, poor communication between operations, poor designed production layout which leads to inefficient material handling of steel frames. These specific suggestions for improvement has led to the second, overall suggestions for improvement, which the authors presents a proposal for a new production layout. The overall improvement proposed by the authors is to switch to a hybrid solution in terms of production system. Merging operations such as painting, installation and packaging in terms of a line, turns out to make the internal materials handling more efficient. Finally, the study ends with a discussion of the results and the method used in this thesis.

Artificial neural networks, so far, have not been used for designing modular cells. Therefore, Self-organizing neural network (SONN) is used in the present research to design minicell-based manufacturing system. Two previously developed methods were studied and implemented using SONN model. Results obtained are compared with previous results to analyze the effectiveness of SONN in designing minicells. A new method is then developed with the objective to design minicells more effectively and efficiently. Results of all three methods are compared using machine-count and materialhandling as performance measuring criteria to find out the best method

Purpose: The aim of the study is to investigate how the material flow, of a high-frequent component family, to an assembly line with volume and product mix variations, can be streamlined. In order to examine this, the aim has been divided into two defined queries. Which factors affect the efficiency of the material flow, for a high-frequent component family, to an assembly line?    How can an effective material flow, for a high-frequent component family, be designed? Methodology: Both a case study and a literature study has been performed, in order to answer the queries. Literature in the areas of material and inventory control, transportation and material handling has been studied. The case study, which was carried out at a company, was based on process mapping combined with interviews and observations. Collected data from the case study have been analysed with support of literature. Findings: Different factors that are restricting the efficiency of the material flow for an assembly line has been identified. Unnecessary operations and inefficient material handling resulted in high cycle times for the material flow. Furthermore, the layout and control of the inventory resulted in long lead time and unnecessary inefficient transportations. Inadequate design and integration of the logistic subsystems has shown to be a significant cause, resulting in limited effectiveness of the studied material flow. On this basis, a new design of the material flow has been proposed, where the holistic perspective and integration are central. A new inventory design and a tugger-train transportation solution along a timed route, reduce the material handling and the number of deliveries. In addition, a pull flow system where consumption controls material replenishment, reduces both inventory levels and the number of inventory buffers. Implications: The purpose of the study has been achieved by solving the defined queries. By identifying factors that reduce the effectiveness of the material flow, a more efficient solution can be designed. The study shows that there are several possible improvement opportunities for the studied material flow. However, only one case study was performed, therefore its ability to create scientific value, can be regarded as limited. Recommendations: For further studies, it may be of interest to study several companies with similar problems to be able to draw general conclusions with scientific depth. / Syfte: Studiens syfte är att undersöka hur materialflödet för en högfrekvent komponentfamilj till en volym- och produktmässigt varierad monteringslina kan effektiviseras. För att kunna besvara denna frågeställning har syftet delats in i två problemfrågor: Vilka faktorer påverkar materialflödets effektivitet för en högfrekvent komponentfamilj fram till monteringslina? Hur kan ett effektivt materialflöde för en högfrekvent komponentfamilj utformas? Metod och genomförande: För att kunna besvara studiens syfte har en fallstudie genomförts parallellt med en litteraturstudie. Litteratur inom områdena material- och lagerstyrning, transporter och materialhantering har studerats. Fallstudien, som har genomförts på ett fallföretag, baseras på en processkartläggning i kombination med intervjuer och observationer. Insamlad data från fallstudien har analyserats med stöd från studerad litteratur. Studiens resultat: Faktorer som begränsar ett materialflödes effektivitet fram till monteringslina har identifierats. En stor andel av materialflödets totala cykeltid kunde kopplas till onödiga arbetsmoment och ineffektiv materialhantering. Ytterligare bidrog lagrets utformning och styrning till långa ledtider samt onödiga och ineffektiva transporter. Bristande utformning och integration av materialflödets delar visade sig vara en betydande orsak till begränsningen av dess effektivitet. Med detta som utgångspunkt har en ny utformning föreslagits där helhetsperspektiv och integrering har varit centralt. En ny lagerutformning, i form av materialtorg, samt en transportlösning med trucktåg utefter tidsbestämd rutt, reducerar materialhantering och antalet transporter. Tillämpningen av ett dragande flöde där monteringslinornas efterfrågan styr materialpåfyllnad, reducerar lagernivåer samt antalet buffertlager i materialflödet. Implikationer: Studiens syfte har uppnåtts genom att båda problemfrågorna har besvarats. Genom att identifiera negativa påverkansfaktorer kan förutsättningar skapas för utformningen av ett effektivt materialflöde. Studien visar att det på fallföretaget finns förbättringsmöjligheter för effektivisering av materialflödet fram till monteringslina. Då enbart ett företag studerats kan resultatet av studien och dess förmåga att skapa vetenskapligt värde, ur ett större perspektiv, anses begränsad. Rekommendationer: För vidare studier kan det vara av intresse att studera flera företag med liknande problematik för att öka studiens generaliserbarhet och förmåga att kunna presentera slutsatser med vetenskapligt djup.

This thesis focuses on control strategies for intralogistics transport systems. It evaluates how switching from central to decentral dispatching approaches influences the performance of these systems. Many ideas and prototypes for implementing decentral control have been suggested by the scientific community. But usually only the qualitative advantages of this new paradigm are stated. The impact on the performance is not quantified and analyzed. Additionally, decentral control is often confused with distributed algorithms or uses the aggregation of local to global information. In the case of the latter, the technological limitations due to the communication overhead are not considered. The decentral prototypes usually only focus on routing. This paper takes a step back and provides a generic simulation environment which can be used by other researchers to test and compare control strategies in the future. The test environment is used for developing four truly decentral dispatching strategies which work only based on local information. These strategies are compared to a central approach for controlling transportation systems. Input data from two real-world applications is used for a series of simulation experiments with three different layout complexities. Based on the simulation studies neither the central nor the decentral dispatching strategies show a universally superior performance. The results depend on the combination of input data set and layout scenario. The expected efficiency loss for the decentral approaches can be confirmed for stable input patterns. Regardless of the layout complexity the decentral strategies always need more vehicles to reach the performance level of the central control rule when these input characteristics are present. In the case of varying input data and high throughput the decentral strategies outperform the central approach in simple layouts. They require fewer vehicles and less vehicle movement to achieve the central performance. Layout simplicity makes the central dispatching strategy prone to undesired effects. The simple-minded decentral decision rules can achieve a better performance in this kind of environment. But only complex layouts are a relevant benchmark scenario for transferring decentral ideas to real-world applications. In such a scenario the decentral performance deteriorates while the layout-dependent influences on the central strategy become less relevant. This is true for both analyzed input data sets. Consequently, the decentral strategies require at least 36% to 53% more vehicles and 20% to 42% more vehicle movement to achieve the lowest central performance level. Therefore their usage can currently not be justified based on investment and operating costs. The characteristics of decentral systems limit their own performance. The restriction to local information leads to poor dispatching decisions which in return induce self-enforcing inefficiencies. In addition, the application of decentral strategies requires bigger storage location capacity. In several disturbance scenarios the decentral strategies perform fairly well and show their ability to adapt to changed environmental conditions. However, their performance after the disturbance remains in some cases unpredictable and relates to the properties of self-organizing complex systems. A real-world applicability has to be called into question.

In today’s fierce competitive global markets, customers are demanding adjustable lot sizes, shorter lead times, higher quality and flexibility; in short, they want it all. In order to stay competitive in the market, companies need to attain both customer satisfaction and cost reduction in production operations. Material Handling Systems (MHS) is the place to accomplish this goal, since they have a direct impact on production. Therefore, the aim of this study was to design an in-house MHS that could be efficient for the production it serves. With this intention, a case-study has been conducted in Bosch Rexroth Japan. During the study, the information gathered through various sources; interviews, observations and measurements. Further, the gathered data is evaluated according to main pillars of the theoretical framework, which includes design principles and physical elements, information and software, human and management. By analyzing the findings from literature review and empirical study, first problems and challenges related to MHSs are identified. Thereafter, possible features that the system should posses are elicited and a design is built out of the selected features. To conclude, the results show that the success is not solely depending on system’s physical attributes; on the contrary, it is more related to rapid and accurate information sharing within the system. Another vital element is the interaction between system and the people, who are utilizing and operating the system. In general terms, the research took MHS design problems from one-dimensional equipment selection processes and enriches them by adding information sharing, human and management angles to design steps.

Purpose - The purpose of this thesis is to identify factors that have an impact on supermarket inventory levels that supply a manufacturing line and investigate how the impact of these factors can be controlled. In order to fulfill the purpose it was broken down into two research questions.   What factors have an impact on supermarket inventory levels supplying a manufacturing line? 2.      How can the impact of these factors be controlled? Method - To answer the research questions a literature study and a case study were conducted. The empirical findings from the case study and the literature study were used to find the answer to the first research question. The identified factors in the first research question were then analysed with the theoretical framework in order to answer the second research question. Different techniques have been used in order to collect necessary data including documentation studies, interviews, observations and basic training in the case company’s procurement system (GILM).   Findings - Total safety lead time, firm time and shortage impact were discovered during the case study. These factors were not to found during the literature study because they were specific parameters that are predetermined in the case company’s procurement system. Internal material handling and supermarket order quantity were factors also found during the case study. The identified factors are divided after which tool or method that can be used to gain control over the factor. Four different tools have been identified as solutions to gain control over the internal material handling. The factors that only have one identified tool as a solution are either case specific or not attentive in the theoretical framework as the other tools.   Implications - The identified factors from the literature study are considered as common factors that can be applied for companies that have a supermarket inventory. If manufacturing companies are facing problems with their supermarket inventory levels they can increase control by investigating the tools and methods presented in this thesis. Contributions - The factors that were identified during the case study have contributed with new discoveries in the field of study, since there is limited research done in this subject regarding supermarket systems.   Research limitations - More case studies could have been performed at similar companies, in order to investigate how generalizable the answers to both research questions are.

During the spring of 2014, Johan Kooiker and Kashira Roil Beto, students in mechanical engineering at Linnaeus University carried out a degree project together with Husqvarna construction products Sweden AB. The topic of this project was "product development" to develop an automated system for assembling cold pressed segments. The project began with studying the current situation to get a clearer picture of the problem and finding out the requirements. The main requirements were studied and implanted in behaviour descriptions of the system. Later on ideas and concepts were generated, which then through rating and screening led to the final concept. The final concept was divided into subsystems and developed in details. The detail work included 3D cad models of unique components and selection of standard component. The final step was to build simple prototypes of the subsystems to test their functions. The prototypes of the subsystems accomplished the main requirements of the company and that led to future investment in final system.

Im Rahmen des Forschungsvorhabens wurde das Wirken von Autokorrelation auf das Verhalten von Materialflusssystemen anhand von Realdaten analysiert. Hintergrund waren theoretische Untersuchungen, die einen deutlichen Einfluss von abhängigen Ereignissen auf die Leistung von Materialflusssystemen erkennen lassen. Mit Hilfe der Projektpartner konnte eine große Menge von Echtdaten zusammengetragen werden. Insgesamt wurden 52 Datensätze auf zeitliche Abhängigkeiten der Ereignisse untersucht. Dabei bestätigte sich die Vermutung, dass Autokorrelation durch z. B. Batchbildung oder Prioritätsregeln allgegenwärtig in Erscheinung tritt. In ca. 95 % aller Datensätze konnte signifikant Autokorrelation nachgewiesen werden. Im Rahmen der Untersuchung konnten eine Reihe unterschiedlicher Korrelationsstrukturen nachgewiesen werden. Diese unterschieden sich sowohl in der Stärke, in der Ausprägung (positiv oder negativ) als auch im Abklingverhalten. Der größte Einfluss auf das Systemverhalten geht von der Stärke und der Ausprägung der Autokorrelationskoefizienten aus. Im Rahmen des Projektes konnten unterschiedliche Verfahren zur Erzeugung autokorrelierter Ereignisse identifiziert und bewertet werden. Beispielhaft zu erwähnen ist die TES-Methode, der Minification- bzw. Maxification-Ansatz oder spezielle Markov-Ketten. Als am besten geeignet hat sich der sog. ARTA-Ansatz herausgestellt. Der ARTA-Ansatz wurde in einer Java-basierenden Software-Bibliothek namens „JARTA“ umgesetzt. Diese ist frei verfügbar sowie variabel und einfach einsetzbar. Durch das Forschungsvorhaben wurde das Bewusstsein um das Auftreten und Wirken von Autokorrelation in logistischen Systemen geschärft. Projektpartner bestätigen, dass durch gezielte Untersuchung auf Abhängigkeiten Fehler bei der Systementwicklung und beim Systembetrieb verringert werden konnten.

Kostnaderna för byggnadsprojekt ökar varje år, detta beror på ett flertal faktorer såsom nya standarder, synen på att bygga miljövänligt samt hårdare krav från byggherrar som vill få projekten klara på kortare tid. För att kunna möta kraven måste byggföretagen hitta nya sätt för att bygga mer effektivt och lönsamt. Ett område med potential för utveckling är logistiken runt om och på arbetsplatsen. Arbetet utgår från bygglogistik, mer specifikt materialhantering samt lossning på arbetsplatsen. Studien har utförts på två olika byggarbetsplatser i Linköping för att kunna analysera likheter och skillnader mellan arbetsplatserna då de har olika förutsättningar. Studien undersöker och belyser de mest kritiska momenten på arbetsplatserna, identifierar hur problemen uppstår och möjliga lösningar till dessa. Data som studien bygger på har samlats in genom intervjuer och observationer. Studien visar på att en stor del utav de problemen som observerades hade kopplingar till planeringen i form utav APD-planer, bristfällig kommunikation samt platsbrist på bygget.

ABSTRACT Purpose: The purpose of the study is to present what a big increase of volume at the material handling process would mean for a company, and how different processes within the handling process would be affected. This study will show, non-value-added processes that can exist within the material handling are also visualized, and how to make a potential effectivization. To be able to answer the aim of the study three research questions was created: How can a company’s material handling handle a volume increase of 30 %? Which non-value-added processes limit the material handling within companies?  What methods exist for inventory management and what are the benefits of these?   Methodology: A literature review have been conducted in parallel with a case and benchmarking study.  The case study contains qualitative interviews, observations and experiment, and by this a process mapping has been conducted to visualizes muda through the process. The benchmarking studies is relying on interviews as well as observations on three different companies. The literature review contains processes that are used for material handling, inventory, lean, automation, layout, cost optimization, delivery capability as well as VMI inventory.     Result: The study result in a visualization of muda in the material handling process at the case company, through this improvement proposals could be delivered regarding the working process. With the visualization as a base a cost estimation regarding individual mudas cost and the following consequences. The benchmarking studies resulted in improvement suggestions at the case company and an indication of what the different methods would mean when adapted. The companies have different aspects in relation to the case company which mean that the different improvement suggestions are of different magnitudes.     Implications: The purpose of the study has been achieved by answering the research questions. By identification of non-value-added through the process curtain points for improvement has been identified. The improvement suggestions have support from the literature review and the benchmarking study. As the study has only been conducted at one company during a curtain period of time the author reserves for a generalization of the identified factors that does not include all companies, and should instead be seen as an indication.     Recommendations: For further studies regarding volume increase at the material handling process should be studied at other companies with other limitations than the case company to further increase the scientific value. / SAMMANFATTNING Syfte: Forskningsstudien syfte är att kartlägga vad en stor ökning av volym vid materialhanteringsprocessen innebär för ett företag och hur olika processer inom denna blir påverkade. I denna kartläggning visualiseras också vilka icke värdeskapande processer som kan finnas vid en materialhantering och hur en potentiell effektivisering kan utföras. För att uppnå studiens syfte har tre frågeställningar formulerats: Hur kan ett företags materialhantering hantera en volymökning på 30 %? Vilka icke värdeskapande processer begränsar materialhanteringen hos företag? Vilka metoder finns att tillämpa för lagerhantering och vilka är fördelarna med dessa?   Metod och genomförande: En litteraturstudie har genomförts parallellt med en fall och benchmarkingstudie. Fallstudien består av kvalitativa intervjuer samt observationer och experiment, i och med detta har en processkartläggning genomförts för att visualisera muda i processens steg. Benchmarkingstudierna bygger på intervjuer samt observationer på tre stycken fristående företag. Litteraturstudien omfattar de processer som tillämpas vid materialhantering, lager, lean, automation, layout, kostnadsoptimering, leveranssäkerhet samt VMI-lagring.   Studiens resultat: Studien resulterade i visualisering av muda i materialhanteringen vid fallföretaget, ur detta kunde förbättringsförslag tas fram gällande de olika momenten i arbetsprocessen. Med visualiseringen som grund skedde en kostnadsuppskattning om respektive mudas kostnader och var dessa får för följder. Benchmarking studierna resulterade i förslag på förbättringspunkter hos fallföretag samt en indikation av vad dessa metoder innebär vid implementering. Företagen hade olika utgångspunkter i förhållande till fallföretaget vilket innebär att de olika förbättringsförslagen är av olika storleksgrad.   Implikationer: Studiens syfte har uppnåtts genom att de frågeställningar som formulerats har besvarats. Genom identifikation av icke värde adderande processteg har punkter för förbättring visualiserats. De förbättringsförslag som framtagits har stöd av litteratur samt benchmarking studie. Då fallstudien endast utförts på ett företag under en tidsperiod förbehåller sig författaren för att en generalisering av de identifierade faktorerna ej gäller för alla företag utan de bör ses som en indikation.   Rekommendationer: Vidare rekommenderas att ytterligare studier gällande volymökning vid materialhantering studeras vid andra företag med andra kravställningar än fallföretaget för att utöka den vetenskapliga grunden.