A methodology for the distributed and collaborative management of engineering knowledge

The problems of collaborative engineering design and management at the conceptual stage in a large network of dissimilar enterprises was investigated. This issue in engineering design is a result of the supply chain and virtual enterprise (VE) oriented industry that demands faster time to market and accurate cost/manufacturing analysis from conception. Current tools and techniques do not completely fulfil this requirement due to a lack of coherent inter-enterprise collaboration and a dearth of manufacturing knowledge available at the concept stage. Client-server and peer to peer systems were tested for communication, as well as various techniques for knowledge management and propagation including Product Lifecycle Management (PLM) and expert systems. As a result of system testing, and extensive literature review, several novel techniques were proposed and tested to improve the coherent management of knowledge and enable inter-enterprise collaboration. The techniques were trialled on two engineering project examples. An automotive Tier-1 supplier which designs products whose components are sub­contracted to a large supply chain and assembled for an Original Equipment Manufacturer (OEM) was used as a test scenario. The utility of the systems for integrating large VEs into a coherent project with unified specifications were demonstrated in a simple example, and problems associated with engineering document management overcome via re-usable, configurable, object oriented ontologies propagated throughout the VE imposing a coherent nomenclature and engineering product definition. All knowledge within the system maintains links from specification - concept - design - testing through to manufacturing stages, aiding the participating enterprises in maintaining their knowledge and experience for future projects. This potentially speeds the process of innovation by enabling companies to concentrate on value-added aspects of designs whilst ‘bread-and-butter’ expertise is reused. The second example, a manufacturer of rapid-construction steel bridges, demonstrated the manufacturing dimension of the methodology, where the early stage of design, and the generation of new concepts by reusing existing manufacturing knowledge bases was demonstrated. The solution consisted of a de-centralised super-peer net architecture to establish and maintain communications between enterprises in a VE. The enterprises are able to share knowledge in a common format and nomenclature via the building-block shareable super-ontology that can be tailored on a project by project basis, whilst maintaining the common nomenclature of the ‘super-ontology’ eliminating knowledge interpretation issues. The two-tier architecture developed as part of the solution glues together the peer-peer and super-ontologies to form a coherent system for internal knowledge management and product development as well as external virtual enterprise product development and knowledge management. In conclusion, the methodology developed for collaboration and knowledge management was shown to be more appropriate for use by smaller enterprises collaborating in a large Virtual Enterprise than PLM technology in terms of: usability, configurability, cost of system and individual control over intellectual property rights

Manufacturing systems interoperability in dynamic change environments

The benefits of rapid i.e. nearly real time, data and information enabled decision making at all levels of a manufacturing enterprise are clearly documented: the ability to plan accurately, react quickly and even pre-empt situations can save industries billions of dollars in waste. As the pace of industry increases with automation and technology, so the need for accurate, data, information and knowledge increases. As the required pace of information collection, processing and exchange change so to do the challenges of achieving and maintaining interoperability as the systems develop: this thesis focuses on the particular challenge of interoperability between systems defined in different time frames, which may have very different terminology. This thesis is directed to improve the ability to assess the requirement for systems to interoperate, and their suitability to do so, as new systems emerge to support this need for change. In this thesis a novel solution concept is proposed that assesses the requirement and suitability of systems for interoperability. The solution concept provides a mechanism for describing systems consistently and unambiguously, even if they are developed in different timeframes. Having resolved the issue of semantic consistency through time the analysis of the systems against logical rules for system interoperability is then possible. The solution concept uses a Core Concept ontology as the foundation for a multi-level heavyweight ontology. The multiple level ontology allows increasing specificity (to ensure accuracy), while the heavyweight (i.e. computer interpretable) nature provides the semantic and logical, rigour required. A detailed investigation has been conducted to test the solution concept using a suitably dynamic environment: Manufacturing Systems, and in particular the emerging field of Manufacturing Intelligence Systems. A definitive definition for the Manufacturing Intelligence domain, constraining interoperability logic, and a multi-level domain ontology have been defined and used to successfully prove the Solution Concept. Using systems from different timeframes, the Solution concept testing successfully identified systems which needed to interoperate, whether they were suitable for interoperation and provided feedback on the reasons for unsuitability which were validated as correct against real world observations

Process Comprehension for Interoperable CNC Manufacturing

Over the last 40 years manufacturing industry has enjoyed a rapid growth with the support of various computer-aided systems (CAD, CAPP, CAM etc.) known as CAx. Since the first Numerically Controlled (NC) machine appeared in 1952, there have been many advances in CAx resource capabilities. The information integration and interoperability between different manufacturing resources has become an important and popular research area over the last decade. Computer Numerically Controlled (CNC) machines are an important link in the manufacturing chain and the major contributor to the production capacity of manufacturing industry today. However, most of the research has focused on the information integration of upper systems in the CAD/CAPP /CAM/CNC manufacturing chain, leaving the shop floor as an isolated information island. In particular, there is limited opportunity to capture and feed shopfloor knowledge back to the upper systems. Furthermore, the part programs for the machines are not exchangeable due to the. machine specific postprocessors. Thus there is a further need to consider information interoperability between different CNC machine and other systems. This research investigates the reverse transformation of the CNC part programmes into higher level of process information, entitled process comprehension, to enable the shopfloor interoperability. A novel framework of universal process comprehension is specified and designed. The framework provides a reverse direction of information flow from the CNC machine to upper CAx systems, enabling the interoperability and recycling of the shopfloor knowledge. A prototype implementation of the framework is realised and utilised to demonstrate the functionalities through three industrially inspired test components. The major contribution of this research to knowledge is the new vision of the shopfloor interoperability associated with process knowledge capture and reuse. The research shows that process comprehension of part programmes can provide an effective solution to the issues of the shopfloor interoperability and knowledge reuse in manufacturing industries.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Acquisition and sharing of innovative manufacturing knowledge for preliminary design

This study investigates the identification, acquisition and sharing of innovative manufacturing knowledge for the preliminary design of complex mechanical components. Such components need to satisfy multiple, often conflicting design and performance requirements. Some degree of innovation may be required, involving the development of new manufacturing processes. The innovative nature of this manufacturing knowledge makes it difficult to define, codify and share, especially during preliminary design, where this can present significant risks in the design process. Current methods of knowledge sharing do not account for the immature nature of innovative manufacturing knowledge and the combined explicit and tacit elements needed to express it. A flexible interpretive research study with inductive and hypothesis testing elements was undertaken to explore this novel knowledge management problem. During the inductive phase, two data collection activities were undertaken to investigate the manufacturing knowledge required for the preliminary design of gas turbine engines. Using a data driven approach, the main findings which emerged were: the need to include an assessment of the maturity of the design process; the need to use a range of tacit and explicit knowledge to effectively share this and the need to manage knowledge across different domain boundaries. A conceptual framework of the findings was used to develop a hypothesis of knowledge requirements for preliminary design. For the hypothesis testing phase, a systematic methodology to identify, acquire and share innovative manufacturing knowledge for preliminary design was developed from the knowledge requirements. This approach allowed both explicit and tacit knowledge sharing. An evaluation of the methodology took place using three different industrial cases, each with a different component / manufacturing process. The evaluations demonstrated that using the range of knowledge types for transferring knowledge was effective for the specific cases studied and confirmed the hypothesis developed

Metodología de implantación de modelos de gestión de la información dentro de los sistemas de planificación de recursos empresariales. Aplicación en la pequeña y mediana empresa

La Siguiente Generación de Sistemas de Fabricación (SGSF) trata de dar respuesta a los requerimientos de los nuevos modelos de empresas, en contextos de inteligencia, agilidad y adaptabilidad en un entono global y virtual. La Planificación de Recursos Empresariales (ERP) con soportes de gestión del producto (PDM) y el ciclo de vida del producto (PLM) proporciona soluciones de gestión empresarial sobre la base de un uso coherente de tecnologías de la información para la implantación en sistemas CIM (Computer-Integrated Manufacturing), con un alto grado de adaptabilidad a la estnictura organizativa deseada. En general, esta implementación se lleva desarrollando hace tiempo en grandes empresas, siendo menor (casi nula) su extensión a PYMEs. La presente Tesis Doctoral, define y desarrolla una nueva metodología de implementación pan la generación automática de la información en los procesos de negocio que se verifican en empresas con requerimientos adaptados a las necesidades de la SGSF, dentro de los sistemas de gestión de los recursos empresariales (ERP), atendiendo a la influencia del factor humano. La validez del modelo teórico de la metodología mencionada se ha comprobado al implementarlo en una empresa del tipo PYME, del sector de Ingeniería. Para el establecimiento del Estado del Arte de este tema se ha diseñado y aplicado una metodología específica basada en el ciclo de mejora continua de Shewhart/Deming, aplicando las herramientas de búsqueda y análisis bibliográfico disponibles en la red con acceso a las correspondientes bases de datos

The development of a manufacturability analysis system for micro-milling

Manufacturability analysis systems (MASs) have been developed to enable the evaluation of manufacturability aspects during the design stage. MASs have been shown to be useful for macro-manufacturing processes but less attention or effort has been put for their development in the scope of micro-manufacturing. This thesis describes the development of a MAS for a micro-machining domain (MicroMAS) with a custom-made 4-axis Miniature Machine Tool (MMT) being the scope of implementation. There are three important components in this study which are; MAS, Uncertainty Evaluation Model (UEM) and micro-milling experiments. The integration between the results from the UEM analysis and micro-machining experiments were being incorporated into the MicroMAS to provide the system with the real condition of the MMT. In MicroMAS, Primitive Feature Analysis (PFA) is introduced as a new technique in gathering information from a CAD model and analysing its manufacturability. The results from the manufacturability assessment in MicroMAS are successfully achieved through the manufacturability index which indicates the relative ease of machining the CAD model and list of related suggestions. UEM is developed to analyse the influence of the errors stemmed from the MMT construction on the geometrical accuracy of the machined micro-parts. The model has allowed a methodology for the errors in a custom-made machine tool to be predicted and to further understand the origin of the errors on the machined micro-part (either from the machine or the process itself). The abilities of the MMT are evaluated through various types of experiments where the surface quality and geometrical accuracy can be concluded to be at an acceptable range. From the experience gained from the research, the development of MicroMAS for micro-milling has been found to be practical in assisting a user to generate micro-parts using the MMT

The development of a manufacturability analysis system for micro-milling

Manufacturability analysis systems (MASs) have been developed to enable the evaluation of manufacturability aspects during the design stage. MASs have been shown to be useful for macro-manufacturing processes but less attention or effort has been put for their development in the scope of micro-manufacturing. This thesis describes the development of a MAS for a micro-machining domain (MicroMAS) with a custom-made 4-axis Miniature Machine Tool (MMT) being the scope of implementation. There are three important components in this study which are; MAS, Uncertainty Evaluation Model (UEM) and micro-milling experiments. The integration between the results from the UEM analysis and micro-machining experiments were being incorporated into the MicroMAS to provide the system with the real condition of the MMT. In MicroMAS, Primitive Feature Analysis (PFA) is introduced as a new technique in gathering information from a CAD model and analysing its manufacturability. The results from the manufacturability assessment in MicroMAS are successfully achieved through the manufacturability index which indicates the relative ease of machining the CAD model and list of related suggestions. UEM is developed to analyse the influence of the errors stemmed from the MMT construction on the geometrical accuracy of the machined micro-parts. The model has allowed a methodology for the errors in a custom-made machine tool to be predicted and to further understand the origin of the errors on the machined micro-part (either from the machine or the process itself). The abilities of the MMT are evaluated through various types of experiments where the surface quality and geometrical accuracy can be concluded to be at an acceptable range. From the experience gained from the research, the development of MicroMAS for micro-milling has been found to be practical in assisting a user to generate micro-parts using the MMT

Acquisition and sharing of innovative manufacturing knowledge for preliminary design

This study investigates the identification, acquisition and sharing of innovative manufacturing knowledge for the preliminary design of complex mechanical components. Such components need to satisfy multiple, often conflicting design and performance requirements. Some degree of innovation may be required, involving the development of new manufacturing processes. The innovative nature of this manufacturing knowledge makes it difficult to define, codify and share, especially during preliminary design, where this can present significant risks in the design process. Current methods of knowledge sharing do not account for the immature nature of innovative manufacturing knowledge and the combined explicit and tacit elements needed to express it. A flexible interpretive research study with inductive and hypothesis testing elements was undertaken to explore this novel knowledge management problem. During the inductive phase, two data collection activities were undertaken to investigate the manufacturing knowledge required for the preliminary design of gas turbine engines. Using a data driven approach, the main findings which emerged were: the need to include an assessment of the maturity of the design process; the need to use a range of tacit and explicit knowledge to effectively share this and the need to manage knowledge across different domain boundaries. A conceptual framework of the findings was used to develop a hypothesis of knowledge requirements for preliminary design. For the hypothesis testing phase, a systematic methodology to identify, acquire and share innovative manufacturing knowledge for preliminary design was developed from the knowledge requirements. This approach allowed both explicit and tacit knowledge sharing. An evaluation of the methodology took place using three different industrial cases, each with a different component / manufacturing process. The evaluations demonstrated that using the range of knowledge types for transferring knowledge was effective for the specific cases studied and confirmed the hypothesis developed.EThOS - Electronic Theses Online ServiceGBUnited Kingdo