Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 79).

Thesis (doctoral)--Helsinki University of Technology, 2005. / Includes bibliographical references (p. 137-155). Also available on the World Wide Web. Myös verkkojulkaisuna.

Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2006. / Dr. Jonathan Colton, Committee Chair ; Dr. John Muzzy, Committee Member ; Dr. Daniel Baldwin, Committee Member ; Dr. John Schultz, Committee Member.

The development of manufacturing systems is faced with progressively tightening time frames, along with growing requirements on planning quality and engineering accuracy. These demands result from significant cost constraints, shortening of product life-cycles, increasing number of product variants and economic needs for rapid time-to-market. Thus, an efficient production ramp-up including the commissioning as the crucial part, becomes more and more important for engineering companies to stay profitable. Virtual Commissioning (VC) is widely considered as promising method to address the challenges associated with real commissioning, but the simulation model building necessary for VC is affiliated with considerable effort and required expertise. VC of manufacturing systems has been a research topic in academia and industry for far more than a decade. Positive results are reported from large companies e.g. from the automotive industry, which are mostly utilising the complex and costly suites of tools in the context of the Digital Factory, rarely from SMEs. However, in particular also SMEs are forced to improve their engineering and commissioning processes, but suites of tools and methodologies used in large companies are not reasonably transferable to SMEs. Rationale for the rare use of VC, besides its general complexity, are a high modelling effort to build the necessary virtual plant models and a lack of availability of methodologies for systematic implementation and reasonable execution of VC. Thus, the main goal of this research is the development of a new systematic simulation study methodology as general guideline for planning, implementation and execution of VC. It is intended to be notably beneficial for engineers from SMEs, as helpful guideline for planning, implementation and execution of VC and to facilitate the substantially high modelling effort required for VC of manufacturing systems. Besides clarifying the requirements and specifying an environment for VC, the criteria to select an appropriate simulation tool have been established. The proposed modular, component based simulation model building has been split into specified procedures for “Low-level Component Modelling”, to be conducted for the components of the decomposed real manufacturing system, and subsequent “High-level Plant Modelling” of the virtual manufacturing system. The applicability of these new approaches has been validated by planning, implementing and conducting a VC for a trackbound transportation system with self-driving transport cars on passive tracks, which is the major subsystem of the manufacturing system used as test-bed at the UASA Hannover. As one main result, a novel workflow for Low-level Component Modelling has been proposed that aims for the gradual relocation of this modelling task as far as possible to the origin of components, in the end the component manufacturers should provide together with the deliverable components their mechatronic component models. This is related to a novel proposal for exchangeable mechatronic component models and an outlined possible implementation with AutomationML.

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M.Ing. / This report covers literature studies of Logistics, Warehousing (as one of the important components in the logistics chain) as well as Just-in-time (JIT) principles (as an important focus recently in logistics operations). The spareparts distribution function of a South African motorcar manufacturing business is then investigated and positioned within the logistics chain and warehousing concept, using the information from the literature study. The implementation of Just-in-time (JIT) principles with regards to specific components of the logistics chain is then investigated in the form of case studies. While most literature only discuss the implementation of JIT principles in a manufacturing environment, this report highlights the fact that substantial benefits can also be obtained by implementing JIT principles in a non-manufacturing environment. This investigation highlights specific benefits as well as negative points which support the literature and which could be used to guide future implementors of JIT principles.

The ability to make rational decisions based on the synthesis of various pieces of information and to eventually arrive at an integrated design plays a very important role in everyday engineering practice. In this paper, a conceptual framework for manufacturing design is obtained through a causal perspective. This framework is used in developing a knowledge-based system that gains insight into the process of arc welding from a few detailed analyses and experiments on simplified models and rationally arrives at an integrated design of the actual process using a hybrid axiomatic-algorithmic approach for design synthesis. The design strategy presented here may also be applied to any manufacturing process in general.

This work stems directly from a manufacturing company's need to improve the quality of its product and increase competitiveness in an industry where a physical understanding of its production process, known as centrifugal spinning, is lacking. Centrifugal spinning is the principal method of producing mineral wool; a product that is predominantly used for thermal and acoustic insulation. The production technique generates wool fibres from a molten jet that is directed to impinge onto four rotating wheels. However, it sometimes, and quite often produces mineral wool fibres of poor quality due to the presence of nonfibrous material or shots; a problem that has so far received little attention. This inquiry was undertaken with a VIew to providing insights into the physical mechanisms governing the formation of fibres and shots. Theoretical analyses and an experiment were conducted to investigate the important non-dimensional groups that govern fibre and shot formation, but concentrating mainly on understanding the mechanics of shot formation. It was established that fibres are formed from the break-up of the thin layer around the rotating wheels. It was also established that shots are formed from droplets produced as a result of jet splashing. Jet splashing is temperature independent since it occurs in a short time-scale from jet impingement with little melt cooling; it is largely governed by force balance and geometrical parameters. Such an observation led to an impinging water jet experiment that was conducted at ambient temperature and its image processed by computer software. From this, it was determined that the significant non-dimensional group that governs jet splashing on a rotating wheel or drum was that due to the jet impact position. The least liquid splashing was found to occur when the jet impinged in the forward position (relative to the direction of rotation) because the depth of fluid underneath the impingement position was always at its minimum. The speed of drum rotation affected jet splashing only up to a critical value, beyond which it had little influence.

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No description available.