A reference architecture provides an overall framework that may embrace models, methodologies and mechanisms which can support the lifecycle of their target domain. The work described in this thesis makes a contribution to establishing such a generally applicable reference architecture for supporting the lifecycIe of a new generation of integrated machine vision systems. Contemporary machine vision systems consist of a complex combination of mechanical engineering, the hardware and software of an electronic processor, plus optical, sensory and lighting components. "This thesis is concerned with the structure of the software which characterises the system application. The machine vision systems which are currently used within manufacturing industry are difficult to integrate within the information systems required within modem manufacturing enterprises. They are inflexible in all but the execution of a range of similar operations, and their design and implementation is often such that they are difficult to update in the face of the required change inherent within modem manufacturing. The proposed reference architecture provides an overall framework within which a number of supporting models, design methodologies, and implementation mechanisms can combine to provide support for the rapid creation and maintenance of highly structured machine vision applications. These applications comprise modules which can be considered as building blocks of CIM systems. Their integrated interoperation can be enabled by the emerging infrastructural tools which will be required to underpin the next generation of flexibly integrated manufacturing systems. The work described in this thesis concludes that the issues of machine vision applications and the issues of integration of these applications within manufacturing systems are entirely separate. This separation is reflected in the structure of the thesis. PART B details vision application issues while PAIIT C deals with integration. The criteria for next generation integrated machine vision systems, derived in PART A of the thesis, are extensive. In order to address these criteria and propose a complete architecture, a "thin slice" is taken through the areas of vision application, and integration at the lifecycle stages of design, implementation, runtime and maintenance. The thesis describes the reference architecture, demonstrates its use though a proof of concept implementation and evaluates the support offered by the architecture for easing the problems of software change.

This thesis describes research into Inspection Plan and Code Generation that has been carried out as part of a research project investigating Information Support Systems for Design and Manufacture. The major theme of this project has been the creation of a skeletal Design to Manufacture Environment which incorporates a feature-based design system, a Machine Planner and Cutter Path Generator for machining an Inspection Plan and Code Generator (the subject of this thesis), and a Manufacturing Data Analysis facility. This experimental environment is supported by a Product Modelling System that permits all geometrical and technological information required to design and manufacture the product to be represented so that full integration can be achieved in the Design to Manufacture Environment. The survey of literature in this thesis covers the wolk of researchers in the field of Product Modelling Environments, in addition to work based on advanced Design to Manufacture systems, before concentrating on research directly concerned with Inspection Plan and Code Generation. The main body of the thesis begins by stating and explaining the objectives of the research and lists the issues that need to be addressed in order to meet these objectives. This is followed by a description of the experimental Design to Manufacture Environment, which includes an explanation of the Product Model and the interaction between it and the inspection application. The higher level issues of Inspection Planning are then discussed before attention is focussed on the individual planning activities that represent the main thrust of the research. Frequent references are made throughout these sections to a series of case-studies (Appendices C and D) based on components supplied by industrial collaborators and processed by an experimental Inspection Plan and Code Generator modelled on the theories promoted by this work. The conclusion of the thesis describes what has been learnt by this research and discusses how adequately the research objectives have been achieved.

The achievement of "better, faster, cheaper" product designs is heavily dependent on providing appropriate information to design teams. One of the essential parts of the information is the manufacturing process information. The aim of this research has been to explore the representation of the capability of the injection moulding process in a software form. The resulting model termed a Manufacturing Model must provide a common source of information to a range of interacting Design for Manufacture applications. These applications in turn would produce feedback advice as the design evolves, to the users in order to assist in their design decisions. The manufacturing information to support injection moulding process has been categorized as mouldability features, mould elements and injection mould machine elements which represent the main entities of the Manufacturing Model. The EXPRESS language and EXPRESS-G have been used to provide a formal non-software dependent representation of the underlying structure of the Manufacturing Model. To explore the use of the Manufacturing Model information to support Design for Manufacturing (DFM) applications the Object-Oriented methodology of Booch has been used. Three DFM applications have been considered, these being Desigu for Mouldability, Supporting Mould Design and the Selection of Injection Machine. An experimental Manufacturing Model, based on the EXPRESS representation, and related DFM applications have been implemented in Object-Oriented form using LOOPS (Xerox 1988). This has been used to show that the capability of the injection moulding process has been captured in the Manufacturing Model and provides support to a range of interacting Design for Manufacture applications. While the EXPRESS language has provided a good tool to capture the structure of the Manufacturing Model, further work has been required to define the functional interactions between entities within the model. Using the object oriented paradigm to implement the Manufacturing Model has been demonstrated. The Booch methodology in addition to EXPRESS has provided the basis to model the functional interaction between the Manufacturing Model entities. As an implementation tool, LOOPS has proven to provide adequate object oriented capability. However there is requirement for software tools which can readily be integrated with other software tools. The research has provided a contribution to a structured, and extensible, approach which should influence future CAB system structures aiming to provide support to Concurrent Engineering.

The extrusion of aluminium alloys involves the shaping of the product from an homogenised billet into a complex shape. In addition the properties of the extrudate are closely related to the processing parameters (temperature, stain rate, and material morphology). Since all the parameters vary throughout the ram stroke and throughout the billet the prediction of the condition of the extrudate is complex. In this study the analysis is accomplished by the use of finite element analysis coupled with sub-illodelling of the structural features. The study is extended to include the lieat-treatment process necessary for precipitation hardened alloys subsequent to the process. The author has published these results in a number of learned journals and these are given in Appendix. After a concise introduction and crirical literature review chapter3 analyses the basic operation of the finite element package(FEM) discussing the procedures involved, the equilibrium equations and the more practical aspect of the mesh morphology and size. Finite Element analysis and material structural models have been integrated using parallel processing technology and program sub-routines. In this section the external inputs are also defined paying particular attention to the friction conditions and the constitutive equations. The thesis then proceeds to describe and analyse the integrated modelling of the process necessary to introduce the user introduction of the equations necessary to produce a comprehensive analysis of the material structural problems. This includes the cellular automata teclu-iiques. Various complex extrusion geometries are analysed and the effects of scaling considered. Development of the extrudate surface and criteria for ptedicting this important feature are coinprehebsivcly covered in chapter 5 whilst chapter 6 considers some special technologies such as the use of pockets to obtain homogenous structures. Isothermal extrusion is also included in this section.

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Much of the work in the area of automated scheduling systems is based on the assumption that the intended execution environment is static and deterministic. The work presented in this thesis is motivated by recognition of the fact that most real world scheduling environments are dynamic and stochastic. It views the scheduling task as one of satisfaction rather than optimisation, and maintenance over creation. This thesis reviews existing work in the area and identifies an opportunity to combine recent advances in scheduling technology with the power of distributed processing. Within a suitable problem-solving architecture it is argued that this combination can help to address the fundamental problems of execudonal uncertainty, conflicting objectives and combinatorial complexity. A scheduling system, DAS, which employs such a problem-solving architecture, is presented. It is distributed, asynchronous and hierarchical, and requires careful management of problem-solving effort. DAS adopts an opportunistic approach to problem-solving and the management of problem-solving effort. The mechanisms which manage problem-solving effort within DAS are also presented. In conclusion it is argued that the architecture and mechanisms presented lend themselves very well to the view taken of the scheduling task.

Termination of heavy-duty synthetic fibre ropes has long been an issue of concern in marine environments. Recent serious rope accidents and new requirements for lighter ropes with better performance in mooring lines have encouraged industry to look for new methods for increasing line performance using existing ropes. One way of increasing rope performance is to use efficient methods for rope termination. This is why the main objective of this study has been to investigate a new method for rope termination. Rope failure usually happens inside or very close to termination due to high stress concentration areas. The new method, "The Vaseghi Stress Relief Socket", has been proposed to improve the high stress concentration areas inside sockets and move failure points along the rope. The new method has increasedthe tensile performance of existing ropes up to 13%. It should also be addedthat the ropes in this study are mainly used in marine environmentsfor mooring oil platforms. Considering the results of the tensile and cycling tests, The Vaseghi Stress Relief Socket, proved a great potential for replacement of existing methods of termination e.g. the splice. It should also be noted that the reproduction of the socket termination is more consistent than that of other methods of termination. Tensile properties of ropes using `The Vaseghi Stress Relief Socket' were initially a matter of concern, for rope termination is the most important feature of ropes.In fact, if there is a termination failure in tensile tests, the rope will not be considered efficient for mooring purpose even though its other performancesare excellent. Load cycling was the second property that was considered. Acoustic Emission monitoring was performed to find out the relation between the load-extension behaviour of the rope using The Vaseghi stress Relief socket and the AE signals. Finally, the finite element modelling of socket helped to investigate the stress concentration areas in the socket to optimise the amount of the reinforcing material and identify the weak point areas in the socket, which could lead to further research studies for new designs.