Showing papers by "Chris McMahon published in 2007"

Development of design for remanufacturing guidelines to support sustainable manufacturing

Abstract: Developing sustainable approaches to manufacture is a critical global concern. Key measures towards this include practicing design for environment (ecodesign), for example by improving remanufacturing efficiency and effectiveness. Remanufacturing is a process of bringing used products to a ''like-new'' functional state with warranty to match. Its significance is that it can be both profitable and less harmful to the environment in comparison to conventional manufacturing. Remanufacturing has a low profile in world economies and is poorly understood because of its relative novelty in research terms. However, environmental and competitive pressures are changing the global and business environment and this is fuelling interest in the practice. This paper provides the background to remanufacturing together with the findings from workshops recently undertaken in the UK as part of research into design and manufacturing approaches to facilitate remanufacturing.

A simulated annealing-based optimization approach for integrated process planning and scheduling

Abstract: A job shop needs to deal with a lot of make-to-order business, in which the orders are usually diverse in types but each one is small in volume. To increase the flexibility and responsiveness of the job shop in the more competitive market, process planning and scheduling modules have been actively developed and deployed. The functions of the two modules are usually complementary. It is ideal to integrate them more tightly to achieve the global optimization of product development and manufacturing. In this paper, a unified representation model and a simulated annealing-based approach have been developed to facilitate the integration and optimization process. In the approach, three strategies, including processing flexibility, operation sequencing flexibility and scheduling flexibility, have been used for exploring the search space to support the optimization process effectively. Performance criteria, such as makespan, the balanced level of machine utilization, job tardiness and manufacturing cost, have been systematically defined to make the algorithm adaptive to meet various practical requirements. Case studies under various working conditions and the comparisons of this approach with two modern evolutionary approaches are given. The merits and characteristics of the approach are thereby highlighted.

Development of robust design-for-remanufacturing guidelines to further the aims of sustainable development

Abstract: Key manufacturing challenges include pollution, natural resource depletion, waste management and landfill space. Remanufacturing, a process of bringing used products to a 'like-new' functional state with warranty to match, is being regarded as a vital strategy in waste management and environmentally conscious manufacturing. There is a paucity of remanufacturing knowledge, particularly in design-for-remanufacturing (DFRem) because of its relative novelty in research terms. This paper outlines the elements of the remanufacturing concept, details existing design-for-remanufacturing research and describes findings from recent UK industrial case studies undertaken to verify and augment previous research. It proposes some fundamental steps required to build on past work to improve the robustness of DFRem methodologies.

Making sense of engineering design review activities

Abstract: Engineering design reviews, which take place at predetermined phases of the product development process, are fundamental elements for the evaluation and control of engineering activities. These meetings are also acknowledged as unique opportunities for all the parties involved to share information about the product and related engineering processes. For product development teams, the knowledge generated during a design review is not as secondary as it may seem; key design decisions, design experiences, and associated rationale are frequently made explicit. Useful work has been carried out on the design review process itself, but little work has been undertaken about the detailed content of the meeting activity; it is argued that understanding the transactions that take place during a meeting is critical to building an effective knowledge-oriented recording strategy. To this effect, an extensive research program based on case studies in the aerospace engineering domain has been carried out. The work reported in this paper focuses on a set of tools and methods developed to characterize and analyze in depth the transactions observed during a number of case studies. The first methodology developed, the transcript coding scheme, uses an intelligent segmentation of meeting discourse transcriptions. The second approach, which bypasses the time consuming transcribing operation, is based on a meeting capture template developed to enable a meeting observer to record the transactions as the meeting takes place. A third method, the information mapping technique, has also been developed to interpret the case study data in terms of decisions, actions, rationale, and lessons learned, effectively generating qualitative measures of the information lost in the formal records of design reviews. Overall, the results generated by the set of tools presented in this paper have fostered a practical strategy for the knowledge intensive capture of the contents of design reviews. The concluding remarks also discuss possible enhancements to the meeting analysis tools presented in this paper and future work aimed at the development of a computer supported capture software for design reviews.

Product representation in lightweight formats for Product Lifecycle Management (PLM)

Abstract: Currently, companies face the unprecedented challenges of the global marketplace, collaborative environments and the entire product lifecycle. There are new requirements for product representations, including: platform/application independence, support for the product lifecycle, rapidly sharing information between geographically distributed applications and users, and protection of commercial security. To meet these, some lightweight representations have been developed and applied in different industries. This paper highlights some limitations in the current applications, and presents a framework of lightweight representations for the product lifecycle. In the proposed framework, a markup method is applied to the whole product lifecycle. The approach is demonstrated with an industrial case study.

Information Maturity Approach for the Handling of Uncertainty within a Collaborative Design Team

Abstract: At the embodiment stage of the product development process (PDP), the definition of mechanisms that allow actors in the design process to exchange immature (e.g. uncertain, incomplete) information is of great importance to ensure reliable communication among actors and for the good progress of the process. Computing systems, such as PDM systems and CSCW systems, are hard to cope with immature design information. This paper presents how a maturity framework can improve the collaborative design process. The focus is put on the collaboration between designers and engineers.

Development and characterisation of error functions in design

Abstract: As simulation is increasingly used in product development, there is a need to better characterise the errors inherent in simulation techniques by comparing such techniques with evidence from experiment, test and in-service. This is necessary to allow judgement of the adequacy of simulations in place of physical tests and to identify situations where further data collection and experimentation need to be expended. This paper discusses a framework for uncertainty characterisation based on the management of design knowledge leading to the development and characterisation of error functions. A classification is devised in the framework to identify the most appropriate method for the representation of error, including probability theory, interval analysis and Fuzzy set theory. The development is demonstrated with two case studies to justify rationale of the framework. Such formal knowledge management of design simulation processes can facilitate utilisation of cumulated design knowledge as companies migrate from testing to simulation-based design.

A generic model for creativity and innovation: overview for early phases of engineering design

Abstract: This paper explores how 'creativity' and 'innovation' are most usefully modelled for the modern design context invariably consisting of conflicting technical, economical, organisational and social demands. Section 2 summarises the experiences and observations of engineers and the most comprehensive theories of creativity and innovation proposed by psychologists and educators, which set the stage for a generic model. Section 3 evaluates and synthesises the scope and use of over 100 commercially available tools to enhance creativity and innovation. We place this in the context of the 'processes of creating' outlined in the psychological literature as well as those generally accepted to lead to internationally competitive outcomes in engineering, business, sociology and literature, among others. The series of tables defines a preliminary Taxonomy of Tools to enable potential users to clarify how and where additional information or help should be solicited, to streamline any stage of engineering design. Section 4 elucidates a 'process of creating' as a generic model, which illustrates how contradictory input data become novel outcomes in processes that co-evolve the bodies of knowledge on both sides of a problem?solution equation. The model, in contrast to previous theories, is not vague ? apparent contradictions between design demands can be resolved in precise steps, as long as the starting point of all actors/stakeholders is made coincident.

An approach for the capture of context-dependent document relationships extracted from Bayesian analysis of users' interactions with information

Abstract: A number of technologies exist which enable the unobtrusive capture of computer interface interactions in the background of a user's working environment. The resulting data can be used in a variety of ways to model aspects of search activity and the general use of electronic documents in normal working routines. In this paper we present an approach for using captured data to identify relationships between documents used by an individual or group, representing their value in a given context--that may relate to specific information need or activity. The approach employs the use of a naive Bayesian classifier to evaluate possible relationships that are derived implicitly from the data. It is intended that the relationships established be stored within an information retrieval (IR) system to aid in the retrieval of related documents where future users arrive at a similar context. In the evaluation of the approach over 70 hours of data from computer users in industrial and academic settings are collected to assess its overall feasibility. The results indicate that the approach provides a useful method for the establishment of identifiable relationships between documents based on the context of their usage, rather than their content.

Knowledge loss in design reviews

Abstract: In a design project, a great deal of information about the aspects of the product being developed and the progress of the project is exchanged during meetings. However, reports which constitute the formal records of meetings are often limited in the extent to which they capture the information exchange. New recording and facilitation technologies for meetings are improving but further work is needed to enable the efficient capture of knowledge and experience from the discourse. The work reported in this paper is part of a project, carried out jointly with Airbus UK, exploring how design experience and rationale can be captured from the discourse of design reviews. In particular, this paper will present a methodology to evaluate the knowledge lost from the formal record of design reviews based on a comparison between transcripts and official minutes. The interpretation of the results is based on a unique information mapping technique. It provides the research team with an essential visual tool reflecting the loss of useful design knowledge for each design issue identified during the meeting. All findings are based on an industrial case study and a survey on the requirements of practicing engineers in leading aerospace companies.

EDCMS - a content management system for engineering documents

Abstract: Engineers often need to look for the right pieces of information by sifting through long engineering documents. It is a very tiring and time-consuming job. To address this issue, researchers are increasingly devoting their attention to new ways to help information users, including engineers, to access and retrieve document content. The research reported in this paper explores how to use the key technologies of document decomposition (study of document structure), document mark-up (with EXtensible Mark-up Language (XML), HyperText Mark-up Language (HTML), and Scalable Vector Graphics (SVG)), and a facetted classification mechanism. Document content extraction is implemented via computer programming (with Java). An Engineering Document Content Management System (EDCMS) developed in this research demonstrates that as information providers we can make document content in a more accessible manner for information users including engineers. The main features of the EDCMS system are 1) EDCMS is a system that enables users, especially engineers, to access and retrieve information at content rather than document level. In other words, it provides the right pieces of information that answer specific questions so that engineers don’t need to waste time sifting through the whole document to obtain the required piece of information. 2) Users can use the EDCMS via both the data and metadata of a document to access engineering document content. 3) Users can use the EDCMS to access and retrieve content objects, i.e. text, images and graphics (including engineering drawings) via multiple views and at different granularities based on decomposition schemes. Experiments with the EDCMS have been conducted on semi-structured documents, a textbook of CADCAM, and a set of project posters in the Engineering Design domain. Experimental results show that the system provides information users with a powerful solution to access document content.

XML-based Representations in Product Lifecycle Management

Abstract: To support a collaborative environment and strengthen information management for the entire product lifecycles management (PLM) of products, there are increasing demands on developing new-generation product representations. The representations need to be of software platform independence, rapid sharing of information between geographically distributed applications and users, support of the entire product life cycle, and protection of commercial security of products. Conventional product representations, e.g., geometric or feature-based computer-aided design (CAD) models, are unable to meet such requirements. The extensible markup language (XML) offers several advantages, such as platform/application-independency, position-independency and machine-interpretability, so that it has the great potential to be incorporated with conventional product representations to form new-generation exchanging formats. This paper presents a survey of the XML-based product representations to support PLM.

Towards a method for profiling engineering documentation

Abstract: Recent years have seen a lot of interest in how people use, generate, save, and search, paper and electronic documents. We build on this and related work to develop a method for profiling engineering documentation. Profiling provides information about: 1) the varieties and types of engineering documents; 2) the strengths and weakness of document manifestations; 3) the patterns of document use within different ‘types’ of engineering company. The method is composed of two elements. A set of facets for describing documents, and a framework with which to contextualize documents.

The fundamentals of an intelligent design observatory for researching the impact of tools, teams and technologies on information use and design performance

Abstract: Central to improving and sustaining high levels of innovative design is the fundamental requirement to maximise and effectively manage design performance. Within the context of design in the 21 st century, where the process is largely digital, knowledge-driven and highly distributed, this involves the creation of tailored design processes, the use of best-performing tool sets, technology mixes and complementary team structures. Managing these important elements can only be achieved through a fundamental understanding of today’s complex, dynamic design environments. However, such detailed understanding is presently unavailable or at least very difficult to obtain. This is due to the lack of research methods for analysing the relationships between tools, teams, technologies and design process performance, the lack of capability to undertake in-situ analysis of design teams, and the limitations imposed on data acquisition and processing. One approach for overcoming the lack of research methods, is to consider what can be thought of as the design information itself and in particular its generation, representation, communication and use. To address the issues of holistic in-situ analysis and data acquisition, an intelligent design observatory is proposed that is specifically focussed on supporting observation and real-time analysis of design teams. This paper describes the underlying information-based strategy to overcome the lack of existing research approaches and reviews the state-of-the-art technologies for data capture, analysis and realtime processing. The paper then sets out fundamental requirements of a design observatory from the designer’s perspective and presents a possible laboratory configuration. Following this, the issues and barriers to designing experiments involving the observation of practising designers are discussed and the paper concludes with examples of possible experiments and how such a laboratory might be used to support a global research programme.

The use of faceted classification in the organisation of engineering design documents

Abstract: The adoption of a product service or support model in place of product provision has implications upon the strategies employed in the organisation and retrieval of engineering information. In order to ensure that such organisational schemes endure over the extended service time spans, the structure of these schemes must cater for all engineering viewpoints and provide the context necessary to comprehend the information content. Traditional, enumerative classification schemes generally cater for a limited viewpoint or perspective, however faceted classification addresses this by concurrently describing multiple aspects or facets of a given document and allowing retrieval to proceed via browsing of a given facet or combination of facets. Faceted classification was first formalised within the field of library science in the early 20 century, and whilst notions of a faceted structures have been appended into primarily enumerative schemes there are few implementations of pure faceted models, arguably as within a library it is not possible to reorder physical documents according to a given facet of interest. Electronic documentation has no such physical restriction, and this has fuelled a resurgence in interest in faceted classification. Whilst the concept of faceted classification as a means of browsing is generally understood; the literature specifying how such a scheme should be created for a given domain is sparse, and distributed across different domains and eras. This paper reviews this literature and proposes a means by which the underlying theory may be more readily applied to engineering design documentation.

Improving confidence in simulation-based design through error functions

Abstract: Understanding of uncertainty in the data and models used in design simulations matures during the design process as the design progresses from vague requirements through to its full embodiment and detail. Failure to take account of uncertainty in the information that is used in and generated from simulation processes poses risks to decisions based upon these. This paper presents a classification scheme based on the extent and nature of uncertainty in the correlations between simulation predictions and the evidence for a specific performance criterion. The classification allows development of a confidence scale and associated error functions for characterizing the discrepancy between the correlations of design performance parameters and evidence, in the presence of uncertainty. Together, the confidence scale and error functions may provide a greater understanding of uncertainty and errors in simulation processes. In the context of parametric design, the approach provides a mechanism for building up greater understanding of the simulation performance across a feasible design space. A case study on the design of shrink-fits is used to illustrate the framework for handling uncertainty in a systematic and organized manner. The theoretical and practical limitations and further work will be discussed.

Observations on data relating to user browsing behaviour and usage of electronic information

Abstract: In this paper the implementation of a software test rig that facilitates the capture of computer-based “activity profiles” is discussed. A case study involving the analysis of profile data for the activities of a designer working in the engineering division of a medium sized enterprise is also presented. It is shown that the capture of data including the time and location of electronic information resources browsed or manipulated during the course of an activity can be achieved with a relatively high level of autonomy. It is proposed that the results will be used to provide for a better understanding of designers’ interactions with electronic information but also aid in the generation of beneficial applications of profile data for the support of designers’ tasks on computer.

The barriers to improving information management in engineering organizations: A study of small to medium-sized enterprises

Abstract: The use of information and the development of more effective strategies for its management is one of the most important issues facing today’s knowledge dependent engineering organisations. For these reasons, considerable work has been undertaken to understand and improve information management within larger organisations. However, where small to medium-sized organisations are considered little empirical work has been undertaken. To address this, a detailed study of the issues concerning information management across ten engineering SMEs from the Advanced Engineering sector has been completed. This paper presents an overview of the study and includes a discussion of the research method and in particular, the important tasks of data collection and data filtering. Following this, the processes of characterising the generic issues and the assessment of causality and dependency between the issues are described. Using the empirical data, a set of fundamental issues is proposed which may be considered to represent the key barriers to improving information management within engineering SMEs. These barriers and their implications are then discussed and a number of important considerations are highlighted. It is also clear that the findings of this study and the understanding gained are not only critical for improving information management but also for the development and planning of an effective information systems strategy within this class of organisation.

An approach to capture design-induced error using an ontology

Abstract: Since engineered systems, e.g. aviation control, have increasingly equipped with automated and computer-supported artifacts, human-system interaction has been an important issue. Understanding the infleunce of design on human performance requires phycological theories that explain human behaviour and cognition. One of the challenges of modelling such theories is to identify complex relations between systems and humans including different task perspectives. To address this problem, we have developed an ontology that specifies which relations are better comprehended when assisted with the theories and have used it to model human errors induced by designs. This paper presents the results of developing such ontology using a supporting tool, i.e. PCPACK.

A Web-based semantic information retrieval system to support decision-making in collaborative design

Abstract: The quality of decision making in collaborative design is highly dependent upon the designer’s ability to seek relevant information and interpret the available information within the appropriate domain to understand the design problem. It is unlikely that right decisions will be achieved based on inaccurate and incomplete information. This paper discusses a Web-based semantic information retrieval system to support decision making in collaborative design. The system has three features to facilitate designers to make better decisions: (1) the system can retrieve accurate information in the sense that it returns the right piece of information at fragment level rather than at whole document level; (2) the system returns information not only with the correct content but also an appropriate context, i.e. with rich semantics; (3) the system provides designers with a navigational graphical user interface which incorporates a concept hierarchy representing domain knowledge that allows inexperienced engineers learn from constant search feedback and to edge towards the final results. In this case, the whole information seeking process is always transparent to the users, who avoid going down blind alleys with zero returns. The system is developed using a J2EE architecture and Web services, and therefore can be hosted on any machine on a network and will allow engineers to access and retrieve information using Web browsers. Based on the experimental exploration of the system, it is concluded that the system offers to facilitate design engineers to reach better decisions in the collaborative environment through better information support.

Toward a method for profiling engineering documentation

Abstract: Recent years have seen a lot of interest in how people use, generate, save and search paper and electronic documents. We build on this and related work to develop a method for profiling engineering documentation. Profiling provides information about 1) the varieties and types of engineering documents, 2) the strengths and weakness of document manifestations; 3) the patterns of document use within different types of engineering company. The method is composed of two elements. A set of facets for describing documents, and a framework with which to contextualize documents.

Implications of inclusive design for design education

Abstract: By 2021 it has been estimated that almost half the UK population will be over 50 and have some physical impairment. Although this trend has made the need to develop a more user-oriented engineering design process more acute, it has proven difficult to reconcile qualitative user knowledge with the traditionally object-oriented design process. It is argued that including users, particularly those with impairments, and understanding their experiences could inform design and help students better understand technical concepts. A framework, from research in Human Computer Interaction (HCI), is suggested as a possible means for integrating user knowledge with engineering design education, practice and research.