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The exchange of information in the industrial environment is essential in order to achieve complete integration and control of manufacturing processes. At present the majority of devices present in the shop floor environment are still used as stand alone machines. They do not take advantage of the possibilities offered by a communication link to improve the manufacturing process. The subject of this research has been centered on the development of a simple, flexible and inexpensive support system for communication and control of manufacturing processes. As a result, a system with these features has been proposed and implemented on a simulated workcell. The area footwear manufacturing was chosen for modelling the workcell. The components of the manufacturing support system were developed using an object oriented approach which allowed modularity and software reuse. In order to achieve communication between the components, a communication protocol was developed following the process defined in the rapid protocol implementation framework. Ethernet was selected for implementing the lower levels of the protocol. Java, a new object oriented programming language used for the implementation of the system, showed that it could became a promising language for the implementation of manufacturing applications. In particular the platform independence feature of the language allows the immediate porting of applications to systems with different features. The manufacturing cell simulation had shown that the times associated with the manufacturing support system operations are compatible for its use in applications where the response times are in the order of one second.

The design of a manufacturing system is normally performed in two distinct stages, i.e. steady state design and dynamic state design. Within each system design stage a variety of decisions need to be made of which essential ones are the determination of the product range to be manufactured, the layout of equipment on the shopfloor, allocation of work tasks to workstations, planning of aggregate capacity requirements and determining the lot sizes to be processed. This research work has examined the individual problem areas listed above in order to identify the efficiency of current solution techniques and to determine the problems experienced with their use. It has been identified that for each design problem. although there are an assortment of solution techniques available, the majority of these techniques are unable to generate optimal or near optimal solutions to problems of a practical size. In addition, a variety of limitations have been identified that restrict the use of existing techniques. For example, existing methods are limited with respect to the external conditions over which they are applicable and/or cannot enable qualitative or subjective judgements of experienced personnel to influence solution outcomes. An investigation of optimization techniques has been carried out which indicated that genetic algorithms offer great potential in solving the variety of problem areas involved in manufacturing systems design. This research has, therefore, concentrated on testing the use of genetic algorithms to make individual manufacturing design decisions. In particular, the ability of genetic algorithms to generate better solutions than existing techniques has been examined and their ability to overcome the range of limitations that exist with current solution techniques. IIFor each problem area, a typical solution has been coded in terms of a genetic algorithm structure, a suitable objective function constructed and experiments performed to identify the most suitable operators and operator parameter values to use. The best solution generated using these parameters has then been compared with the solution derived using a traditional solution technique. In addition, from the range of experiments undertaken the underlying relationships have been identified between problem characteristics and optimality of operator types and parameter values. The results of the research have identified that genetic algorithms could provide an improved solution technique for all manufacturing design decision areas investigated. In most areas genetic algorithms identified lower cost solutions and overcame many of the limitations of existing techniques.

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.

Despite the arguments in favour of the application of computers in temporary works design, as highlighted in previous research, there was a lack of suitable software at the start of this research. The main objective of this research has been to design and develop software for a major temporary works item. Formwork design was selected from several classes as it provided a larger problem domain. Achieving the main objective necessitated the establishment of a strategy for implementing software in temporary works design using a systems engineering approach. After studying the state-of-the-art of computer application in engineering, construction, and temporary works design, an integrated program network strategy was established for implementing software in temporary works design. This involved the coupling of microcomputer-based packaged Computer-Aided Drafting and Database Management Systems with temporary works design applications. The coupling was achieved through the combination of a database/executive approach. This strategy was then used to design, develop, and validate a computer-aided design system for formwork. To establish the formwork design process, contemporary formwork design methods were studied by reviewing literature and holding informal discussions with eight practicing formwork designers. This study, coupled with an analysis of the formwork designer's. tasks, enabled a functional specification to be produced for a computer-aided design system for formwork. This was used to establish six individual modules that make up the system as follows: a formwork database management module; a concrete pressure modelling module; a rational formwork design module; a detailed form work design module; a drafting module; and a schedule of quantities and cost quotation module. A windowing and menu based human-computer interface was designed and developed for the applications to be developed. The system was produced by designing, developing and testing individual modules, which were finally integrated to form a comprehensive Formwork Integrated Computer-Aided Design System (FICADS). The functions integrated include the analysis/design, drafting, scheduling of quantities, and cost estimating of formwork. The system was tested and assessed by means of several case studies and demonstrations to expert form work designers which proved favourable. The main achievement has been the development of a computer-aided design system for formwork that was acceptable to formwork designers. In the development of the system, a conceptual framework within which temporary works design systems can be developed with great flexibility, confidence and a minimum of programming effort has been established.