The thesis presents an approach to adaptive decision making strategies to reduce bottlenecks in a drilling operation and to extend tool life. It is an attempt to portray the real drilling system in a typical Flexible Manufacturing System (FMS) layout. The system designed serves as back end intelligence to drilling machines (INTELLIDRILL) in a Flexible Manufacturing System for making dynamic and real time decisions. INTELLIDRILL uses mathematical and adaptive tool reliability models to simulate the machining conditions and tool availability for an operation based on history of tool failures. The results are used to compute the machining parameters and the tools required for an operation. INTELLIDRILL can devise strategies for different tool materials to operate on batches of different materials. INTELLIDRILL decisions could lead to significant savings in tooling costs and reduction in flow line bottlenecks.

This thesis presents contributions within two domains of manufacturing system development. The first domain is systematic design of product and manufacturing system. The second domain is model based co-operative development between manufacturing companies and manufacturing system suppliers. The axiomatic design framework for design is used to describe the product design and the manufacturing system design. The most important contributions are that product properties and analysis of product function are considered when specifying the manufacturing system. The systematic adaptation of product to the selected manufacturing solution is another contribution. A new concept of manufacturing phase functional requirements has been defined in order to cope with requirements from the manufacturing process on the in process product. The co-operative concept is based on the use of ISO 10303-214 for specification and communication of proposed systems and equipment. The concept has been tested using real project information in prototype implementation / QC 20100913

The thesis presents an approach to adaptive decision making strategies to reduce bottlenecks in a drilling operation and to extend tool life. It is an attempt to portray the real drilling system in a typical Flexible Manufacturing System (FMS) layout. The system designed serves as back end intelligence to drilling machines (INTELLIDRILL) in a Flexible Manufacturing System for making dynamic and real time decisions. INTELLIDRILL uses mathematical and adaptive tool reliability models to simulate the machining conditions and tool availability for an operation based on history of tool failures. The results are used to compute the machining parameters and the tools required for an operation. INTELLIDRILL can devise strategies for different tool materials to operate on batches of different materials. INTELLIDRILL decisions could lead to significant savings in tooling costs and reduction in flow line bottlenecks.

The objective of this dissertation is to enhance the overall understanding of practical manufacturing systems by using rigorous academic approaches, primarily queueing theory. The scope spans from the performance of a single manufacturing process to the performance of a manufacturing system. Queueing models are commonly used to evaluate the performance of manufacturing systems. Exact M/M/1 or approximations of G/G/1 models are usually adopted to describe the behavior of a single machine system. However, when applying queueing models to a single machine, some practical issues are encountered. A real machine is subject to different types of interruptions, such as breakdowns, setups and routine maintenance. The proper queueing models under interruptions are presented. The behavior of manufacturing systems is explored by first investigating the underlying structure of tandem queues. We introduce two properties describing the dependence among servers in tandem queues, namely the intrinsic gap and intrinsic ratio, and develop a new approximation approach. The approach exploits what we call the nearly-linear and heavy-traffic properties of the intrinsic ratio. Across a broad range of examined cases, this new approach outperforms earlier approximations that are based on the parametric-decomposition and diffusion approximation approaches. We also demonstrate its use with historical data to achieve very accurate queue time estimates. Furthermore, based on the structure of tandem queues, a way to model the performance of manufacturing systems has been developed.

This thesis concerns with design of manufacturing system for specific company. Object of manufacture is warmwater boiler for solid fuels. Analysis of this object, design of necessary technologies, manipulation and transportation concept, layout concept and economic efectiveness of investment realization evaluation are apart of this thesis.

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To compete, manufacturing companies need production systems that quickly can respond to changes. To handle change drivers such as volume variations or new product variants, reconfigurability is advocated as a competitive means. This implies an ability to add, remove, and/or rearrange the structure of the production system to be ready for future changes. Still, it is not clear how the production system design process can capture and support the design of reconfigurable production systems. Therefore, the objective of this thesis is to increase the knowledge of how to support the design of reconfigurable production systems. Reconfigurability could be defined by a number of reconfigurability characteristics including convertibility, scalability, automatibility, mobility, modularity, integrability, and diagnosability. In eight case studies, reconfigurability characteristics in production system design were studied in order to investigate reconfigurability needs, knowledge, and practice in manufacturing companies. In three of the case studies reconfigurable production systems were studied to identify the links between change drivers and reconfigurability characteristics. In the remaining five case studies, reconfigurability in the production system design processes was addressed in terms of needs, prerequisites, and consideration. Based on the literature review and the case studies, support for reconfigurable production system design is suggested including two parts. The first part comprises support for analyzing the need for reconfigurability. Based on relevant change drivers the need for reconfigurability must be identified to enable selection of right type and degree of reconfigurability for each specific case of application. A comprehensive view of the reconfigurability characteristics is presented and links between change drivers and reconfigurability characteristics are described. The characteristics are divided into critical characteristics, that lead to a capacity or functionality change of the production system, and supporting characteristics, that reduce system reconfiguration time but do not necessarily lead to a modification of functionality or capacity of the production system. The second part provides support in how to consider reconfigurability in the production system design process. A holistic perspective is crucial to design reconfigurable production systems and therefore constituent parts of a production system are described. According to their character physical, logical, and human reconfiguration must be considered through the whole production system design process.

Purpose: The purpose of the study is to develop an investment model which can be applied during the design of a manufacturing system, that considers DMS, FMS, and RMS. With the aim of the developed model is to give decision makers monetary basis for the added from changeability. To fulfill the purpose three research questions was created:   What methods in academia are currently used to evaluate changeable manufacturing system investments?  What methods in industry are currently used to evaluate manufacturing system investments? How can an investment model be adapted to incorporate both academia and industry preferences? Method: A single-case-study was conducted within a company that is transitioning into a more reconfigurable manufacturing system. This created an empirical framework for a practical model. In parallel with the case study a literature study was conducted to attain a theoretical framework for the study. The first research question was answered with the literature study. The second research question was answered through the case study, including document studies, interviews, and a focus group, complemented with a literature study. From the theoretical and empirical framework, research question three was answered by developing the investment model following the model creation method suggested by Mitroff et al. (1974).  Implication: The wide adoption of the reconfigurable manufacturing system has yet to be fulfilled in industry, partially hinder by finding economic motivation at the investment evaluation of such a system. The focal company and most other western companies use a net present value to evaluate investments. This approach has been proved inadequate to describe the benefits of a changeable system. Literature suggests that a real option approach could successfully describe the benefits of changeability. However, the approach has been perceived by industry to be too complex. Therefore, a model needed to have enough complexity to comprehend aspect of changeability, while still be simplistic enough gain acceptance from industry. The developed model supplements traditional NPV evaluation with a real options approach, adding scenarios to incorporate uncertainties. The study indicates that it is possible to present the monetary value of added flexibility from changeable manufacturing systems in a simplistic way.

The aim of this paper is to identify the enablers, barriers and benefits of implementing reconfigurable jigs in the off-site manufacturing of unique house elements. Due to de- mands on customization, volume and lowering the cost, there is a need to increase flex- ibility in the industry. The paper focuses on mainly two phases of implementation, which are manufacturing, design and engineering. The research questions are answered by applying a single case study method, taking place in a Swedish house manufacturing company. The study consists of four different techniques – interviews, time study, observations, and questionnaire which are sup- ported with an additional literature review. Hence, research questions are answered from a triangulation approach providing nuanced and dynamic perspectives. From observations and time study it is concluded that in current situation, changeover in manufacturing is time-consuming due to the difference in complexity of product var- iants, along with a complex and inefficient setup process that is not responsive to a changeable environment. Findings imply that the barriers in both phases include lack of knowledge about reconfigurability, communication, current capabilities of CAD sys- tems as well as training and education. Enablers are found to be awareness of the needs of improvements, long-term mindset and working with product platforms. The benefits of implementing reconfigurable jigs include a reduction of setup time in manufacturing, better storage and sharing of information along with a better interpretation of that in- formation, a better structure in the organisation.