Reusability in manufacturing, supported by value net and patterns approaches

The concept of manufacturing and the need or desire to create artefacts or products is very, very old, yet it is still an essential component of all modem economies. Indeed, manufacturing is one of the few ways that wealth is created. The creation or identification of good quality, sustainable product designs is fundamental to the success of any manufacturing enterprise. Increasingly, there is also a requirement for the manufacturing system which will be used to manufacture the product, to be designed (or redesigned) in parallel with the product design. Many different types of manufacturing knowledge and information will contribute to these designs. A key question therefore for manufacturing companies to address is how to make the very best use of their existing, valuable, knowledge resources. […] The research reported in this thesis examines ways of reusing existing manufacturing knowledge of many types, particularly in the area of manufacturing systems design. The successes and failures of reported reuse programmes are examined, and lessons learnt from their experiences. This research is therefore focused on identifying solutions that address both technical and non-technical requirements simultaneously, to determine ways to facilitate and increase the reuse of manufacturing knowledge in manufacturing system design. [Continues.

Managing reuse in manufacturing system modelling and design: a value net approach

In the past, reuse programs have assumed that technical solutions would overcome barriers to effective reuse. However, recent retrospectives of reuse programs show that organizational factors can greatly affect the implementation of a reuse program. Reuse is often approached as an independent collection of tools and techniques, and the technical and non-technical aspects are commonly examined separately. This research proposes that all the factors affecting reuse are interdependent and therefore should be studied simultaneously. It is therefore very important that all elements and relationships are identified and documented in a structured, clear manner. The concept of value nets, based on game theory has been identified as a means of capturing the different factors involved in the reuse driven software process. The value net is a useful model for viewing multiple interactions from various perspectives. The value net of the reuse-driven software development process is a map of the various factors and players identified in the reuse process, and the interactions occurring between the players. Hence the reuse value net helps in identifying the important factors that can provide the points of leverage to make the reuse process more efficient

Knowledge sharing between design and manufacture

Object-oriented modelling has become an established technique for product and manufacturing knowledge representation. Various models offering generalised classes and class hierarchies have been proposed for this purpose. Additional bespoke classes are however typically required for specific domain representations. This causes problems when knowledge needs to be shared between domains using different models to describe common entities. These issues are especially complex when several systems are involved. For example, a designer accessing product, manufacturing, and third party systems may face multiple definitions of components, facilities and processes. This paper proposes a model that addresses some of these issues. The proposed model can describe manufacturing knowledge without additional bespoke classes. The detailed semantics of the model are based on recent work on ontologies, notably the Process Specification Language (PSL). Whilst PSL provides detailed semantics, it is not inherently object-oriented. The integration of PSL with object-oriented modelling methods is therefore the principle contribution of this work

Knowledge reuse in manufacturability analysis

This paper proposes a knowledge representation method that supports greater reuse of manufacturing knowledge in design. The method draws on recent research into object-oriented product and manufacturing models, and problem solving agents. A research platform is proposed, and the results of a test case (based on a simplified jet engine combustion chamber) are described. The paper concludes with three basic principles of reuse, i.e. product/process separation, procedural/declarative knowledge separation, and guidelines for the optimum location of rules and constraints within product/manufacturing models

Sharing manufacturing knowledge

Manufacturing and design knowledge is typically distributed across a variety of functional domains such as quality analysis, cost estimation, and manufacturability evaluation. Knowledge Based Systems typically use modelling constructs to represent the entities within these domains, but this leads to difficulties when knowledge needs to be shared between domains. Independently developed constructs often describe The same entities may be described by different modelling constructs resulting in a requirement for complex mappings between common constructs. The use of constructs based on neutral standards eases these difficulties with the Process Specification Language (PSL) the most developed ontology for manufacturing processes. In this paper PSL is used as a neutral ontology for manufacturing knowledge in a design environment