The aim of this research was to understand and solve problems associated with the integration of a Machine Planner within a product model environment. This work was carried out in conjunction with other researchers, pursuing parallel integration issues related to pre-production proving and product data representation. Product data representations of component level planned, processes and feature level process data have been explored as sub-sets of -a product data model to aid integration. Geometric queries on a cell decomposition solid, model. have been explored as a means of providing feature geometric interaction data, while the dimensional interactions between features have also been addressed. Product data representations have been modelled using a prototype software tool, providing an environment for the exploration of the integration of a Machine Planner using a feature based design approach. Necessary Machine Planning functions have been implemented, using the ADA programming language, to explore the integrating capability of the product model environment, concentrating on the use of a prismatic benchmark component. Using the experimental implementation, setup and operation plans have been produced and machining part programs generated from product model representations of variants on the benchmark component. These have been successfully machined using a3 axis vertical machining centre. Such experiments, as well as others in conjunction with co-researchers, have shown that a product data model can provide a common base of data for the integration of a range of design and manufacturing activities.

An important element for the integration of CAD/CAM is the representation and handling of data used during the design and manufacturing activities. The use of features and product modelling techniques bring a better handling of this data and provide CAD/CAM with an excellent platform for integration. The thesis explores the use of a predefined set of features in a product modelling environment for the design and machining of rotational components. Theword features in this research implies a set of functional, geometrical and technological information with a unique form. Those features are pre-defined and comprise of a limited number of elements which carry the information related to design and manufacturing activities. The thesis is divided into three main parts. The first part contains a review of topics related to the research e. g. group technology, component features, CAD/CAM and also contains a literature survey of related research works. In the second part the "features" are defined and presented. Also the product modelling environment is explained and the basic rule based procedures which are used to automatize the operation planning activities are presented. In the last part a description of the case-studies used for automatic NC code generation is presented followed by a discussion of the results. Lastly, the conclusions are drawn and ideas for further work presented.

Building contractors are unhappy about the existing post-tender use of the bills of quantities, particularly the way in which data produced by the estimator may be independently produced again or amended to a suitable format by other management functions. This research aimed at proposing better formats and presentations for the estimating data in order to reduce the repetition and re-work involved in the post-tender use of estimating data, hence to reduce the complexities in data flow in building contractor organizations. The work was primarily carried out for the Sri Lankan industry. To establish the scale and nature of the problem, past work on the format and presentation of estimating data and its current management was studied through literature, interviews and discussions with professionals in ten case studies. Proposals were formulated defining; an efficient classification and coding system, a well defined library structure, a new format to the contractor's copy of the estimate, and effective uses of the computer. The main proposal was to split the unit rate into its components and to provide a breakdown of resource requirements for each bill item. The documents prepared in two test projects were used to demonstrate the feasibility of the proposals in the earlier case studies, and feedback was obtained on the use and extent of use of the improved estimate in post-tender works. A live project was undertaken to investigate the practicability of implementing of the proposals. Finally, an independent survey, without disclosing the results derived from test projects, case studies and the live project was carried out to assess the acceptability of the proposals in the whole industry. All practical work was undertaken in Sri Lanka. The main conclusions derived from these works are; Any research that would investigate the contractor's efficient post-tender use of estimates hould be addressed to contractor organisations; and any proposal that would improve the contractor's data management should be based on contractor's presentation of the estimate. Although the contractors widely use the estimate in their management functions, the full potential is not obtained throughout the contract. Substantial re-work exists in the use of estimate in contractor's post-tender works. The average extent of use of the estimating data was measured at 50% the other 50% of data required re-work. Proposals presented in this research would increase the extent of use of the estimate, hence improve the contractor's data management. The new average extent of use of estimating data (after the introduction of proposals) derived from case studies was 75%. This new average, when compared with the earlier average (50%) showed a 50% possible improvement in the extent of use of estimate in the industry. Test projects, the live project and the independent survey, all showed that the proposals are not only feasible and practicable to implement in contractor organizations, but also acceptable in the whole industry as solutions which would improve the extent of use of the estimate and reduce the complexity of data flow in contractor organizations. The significance of these conclusions is that any contractor organization can adopt the proposals to improve their management because not only has their practicability been investigated but also their acceptability in the whole industry in Sri Lanka as a solution to data complexities is established. The conclusionsa re also of value to other countries.

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This thesis is primarily concerned with conceptual work on the Manufacturing Model. The Manufacturing Model is an information model which describes the manufacturing capability of an enterprise. To achieve general applicability, the model consists of the entities that are relevant and important for any type of manufacturing firm, namely: manufacturing resources (e.g. machines, tools, fixtures, machining cells, operators, etc.), manufacturing processes (e.g. injection moulding, machining processes, etc.) and manufacturing strategies (e.g. how these resources and processes are used and organized). The Manufacturing Model is a four level model based on a de—facto standard (i.e. Factory, Shop, Cell, Station) which represents the functionality of the manufacturing facility of any firm. In the course of the research, the concept of data—driven applications has emerged in response to the need of integrated and flexible computer environments for the support of design and manufacturing activities. These data—driven applications require the use of different information models to capture and represent the company's information and knowledge. One of these information models is the Manufacturing Model. The value of this research work is highlighted by the use of two case studies, one related with the representation of a single machining station, and the other, the representation of a multi-cellular manufacturing facility of a high performance company.

This thesis describes a novel approach to the high speed automatic stitchmarking of shoe upper components by integrating an electrographic printer with a shape recognition system. A critical review of recognition system parameters selects the currently known shape parameters which are most suitable for use in a high speed recognition system with the large number of different shoe components found in a typical shoe factory. These are compared with the parameters actually used in the previously developed recognition system to be used for stitchmarking. A discussion of printing technologies suitable for marking shoe materials with computer generated patterns follows. It is concluded that an electrographic printer has the best combination of characteristics. There follows a description of experiments demonstrating xerography on shoe upper materials, and the design of a system integrating a low-cost laser printer to the recognition system which proved the concept of continuous automatic stitchmarking. With this performing satisfactorily, the system was converted to use a high speed printer requiring the use of an advanced graphics processor for handling the data transformations and interfacing with the printer. Modifications to the printer for operation with shoe materials are described, together with the need for a special toner. A full description of the resulting stitchmarking system is given, followed by details of analyses of its performance. Individual chapters are devoted to the accuracy, recognition efficiency, and the timing of the system. A potential bottleneck in determining the orientation of certain difficult shapes is identified, and faster methods for dealing with these are specially investigated. This concludes that the best approach is to optimise the present method and accelerate the calculations by using a more advanced microprocessor. A discussion of the general running of the machine includes details of problems which occurred with the modified printer mechanism and how these were overcome. Finally, suggestions are made for incorporation in an improved system capable of handling larger shapes with a tenfold speed increase.

The processes of estimating, planning and control within the building industry are seldom fully integrated. This study considers the integration of the processes based on production data collected from several projects. The aim of the research is to investigate the feasibility of the integrated approach as a means of improving the estimating, planning and control processes within the construction industry. Selected cost significant work sections are considered in the study and production data are formulated based on feedback information from several first sample projects. Comparisons are made between average production data and individual project data. A structured systems analysis of the collaborating body identifies existing processes and production orientated information requirements. A model and working system prototype are developed which illustrate integration of the processes and generation of management information. Application of the model as a basis for estimating and planning at various levels of detail is demonstrated. Forecast-observation diagrams provide the necessary control mechanism for monitoring production outputs. Forecasts on a second independent sample of projects are assessed based on tolerances of performances from first sample projects. Accuracy of average forecasts from the model are compared with other data sources, these being estimators' data used in the preparation of the estimate, and bonus surveyors' targets used during the production process. The research concludes that the production data and model give a worthwhile improvement over existing methods in forecasting average productivity performances when methods of placing can be clearly identified and related to work packages. The production data and model are insufficiently accurate to give a worthwhile improvement when measured items cover work packages of varying degrees of complexity, and when proportioning methods are used to obtain production data for different categories of items which collectively represent work packages. Assessment of the model together with refinements are also discussed.

Computer simulation is a well-established decision support tool in manufacturing industry. However, factors such as wrong conceptualisation, inefficient input data modelling, inadequate verification and validation, poorly planned experimentation and lengthy model documentation inhibit the rapid development and deployment of simulation models. A serious limitation among the above factors is inefficient data modelling. Typically, more than one third of project time is spent on identification, collection, validation and analysis of input data. This study investigated potential problems which influence inefficient data modelling. On the basis of a detailed analysis of data modelling problems, the study recommends a methodology to address many of these difficulties. The proposed methodology, discussed in this thesis, is called MMOD (Methodology for Modelling Of input Data). An activity module library and a reference data model, both developed using the IDEF family of constructs, are the core elements of the methodology. The methodology provides guidance on the best way of implementation and provide a tool kit to accelerate the data modelling exercise. It assists the modeller to generate a customised data model (entity model), according to the knowledge gained from the conceptualisation phase of the simulation project. The resulting customised data model can then be converted into a relational database which shows how the entities and relationships will be transformed into an actual database implementation. The application of the MMOD through simulation life cycle also enables the modeller to deal with important phases in the simulation project, such as system investigation, problems and objective definitions and the level of detail definitions. A sample production cell with different level of detail has been used to illustrate the use of the methodology. In addition, a number of useful methods of data collection and the benefits of using a MMOD approach to support these methods and data rationalisation which accelerates the data collection exercise are also covered. The aim of data rationalisation is to reduce the volume of input data needed by simulation models. This work develops two useful data rationalisation methods which accelerate the data collection exercise and reduce the model complexity. This work produced a novel approach to support input data modelling in simulation of manufacturing system. This method is particularly useful when the complex systems are modelled.

The author has investigated software support tools to enable concurrent design for injection moulding, and the view is taken that the kernel for a manufacturing system can be defined as the source of product and manufacturing information which must be available for each application. The Product model provides a consistent source of product information as the design evolves, and the Manufacturing model captures information related to manufacturing resources and processes to support product realisation.

The study relates to manufacturing conditions in a particular company. Flow synthesis and cell formation analysis have been conducted. A modification of methodology proposed by other researchers has assisted analysis. The main investigation is concerned with modelling, simulation and evaluation of seven alternative FMS configurations conceived for the machining cell manufacturing prismatic parts. The alternative systems encompass 6 CNC machines with (i) manual transport of materials and tools, (ii) with two and four station automated pallet changers, (iii) conveyor system, (iv) stacker crane, (v) rail guided shuttle, and (vi) AGV transport.