Abstract: Decisions are an important part of Concurrent Engineering and engineering design in general. Accordingly, more attention should be paid to the means and methods for making these decisions. In this article, a utility-based decision support method for the selection of an engineering design is presented. The utility-based selection decision support problem (u-sDSP) is a synthesized construct that facilitates selection decisions involving trade-offs among multiple, conflicting attributes and mitigation of risk associated with uncertain performance with respect to the attributes considered. The negative impact of unnecessary iterations on the product development cycle is reduced via the assurance of preference-consistent outcomes. Specifically, utility theory provides a mathematically rigorous means of clarifying and capturing designer preferences as well as identifying a preferred alternative in the context of stochastic uncertainty, while the selection decision support problem (DSP) - the construct within which utility theory is employed - facilitates the effective use of engineering judgment for (1) formulating and bounding decisions and (2) establishing a proper context. Application of the u-sDSP is illustrated with an example from rapid prototyping (RP), in which the goal is to select the appropriate technology and material combinations for testing the snap-fit design of a light switch cover plate assembly.

Abstract: In this article, an argument for validation of design-decision methods is presented. In the process of justifying the need for validation, several criteria for a valid design-decision method are introduced. These criteria represent a starting point from which the research community can continue to debate and ponder the validation issue. Under these criteria, a critical empirical investigation of two popular decision support methods, the House of Quality and Suh’s Axiomatic Design, is presented via a simple design problem and both are shown to violate some portion of the proposed definition of validity. The goal of this article is to raise awareness of potential flaws in popular design-decision aids and to promote debate on design validation within the concurrent engineering research community.

Abstract: As functional (total care) products emerge in the jet engine industry, the need for product life-cycle models capable of definition and evaluation of life cycle properties increases, since functional products (FP) includes both hardware and service. Recent life-cycle models are intended for hardware products and mostly handle design and manufacturing knowledge. The aim of this article is to present a design approach that extends the evaluation capabilities beyond classical hardware design and manufacturing evaluation. The focus has been to introduce evaluation of manufacturing and post-manufacturing activities in evaluation of conceptual designs. For this purpose, a model has been proposed to handle the information flow between teams when developing structural jet engine components. A case study, in which the proposed model was used in cooperation with a jet engine component manufacturer, is presented. Aspects concerning design, manufacturing, performance, and maintenance of jet engine flanges were included in the example by means of a knowledge based engineering (KBE)-system coupled to databases and spreadsheets. The model is more suitable than recent work for the development of hardware parts of functional products (HFP), since knowledge from more product development disciplines is included. As the engineer changes the design and directly assesses the life-cycle cost (LCC) and how the changes impact the interface to other jet engine components, more knowledge on the impact of design decisions is available at hand for the engineering designer than without the model.

Abstract: Concurrent engineering employs a set of functional disciplines to simultaneously perform the tasks that lead to a product satisfying a list of customer needs. Quality function deployment (QFD) is a methodology that has been broadly used to listen to the voice of the customer. This article intends to improve the use of QFD in concurrent engineering by adoption of axiomatic design (AD) principles, namely the independence of functional requirements and the hierarchical decomposition following a zigzag path. The conclusion is that the inclusion of these AD concepts avoids multilevel iterations in the QFD approach, which can significantly reduce the lead time and costs.

Abstract: The article presents cost modeling results from the application of the Genetic-Causal cost modeling principle. Industrial results from redesign are also presented to verify the opportunity for early concept cost optimization by using Genetic-Causal cost drivers to guide the conceptual design process for structural assemblies. The acquisition cost is considered through the modeling of the recurring unit cost and non-recurring design cost. The operational cost is modeled relative to acquisition cost and fuel burn for predominately metal or composites designs. The main contribution of this study is the application of the Genetic-Causal principle to the modeling of cost, helping to understand how conceptual design parameters impact on cost, and linking that to customer requirements and life cycle cost.

Abstract: The early phase of design intrinsically contains multiple sources of uncertainties in describing the design, and nevertheless the decision-making process at this phase exerts a critical effect upon drawing a successful design. Recently, set-based concurrent engineering (SBCE) has been attracting public attention as an emerging CE paradigm. Representing and communicating set-valued information are useful in handling engineering uncertainties and efficient for the collaboration between designers in the CE environment. Even if we can readily know that SBCE is efficient and powerful enough for large-scale design and management, the existing literature does not give the details of methods to achieve SBCE principles. We have developed a computer-based framework, called ‘preference set-based design’ (PSD), for implementing SBCE principles, which consists of set representation, propagation, modification, narrowing, and aggregation methods. This article focuses on the set representation and aggregation methods tha...

Abstract: The diversity in software used to support collaborative design and concurrent engineering requires the implementation of newtechnologies in order to ensure the integration between the various activities of the product development process. Most of the time, companiescan not afford to spend the time and the funds required to enhance their IT and software resources. This is often the case of small and mediumcompanies. Nowadays, in mechanical design, the needs for product data sharing between Computer Aided Design (CAD) and finite elementanalysis (FEA) activities have been fairly increased even for small companies. This article aims at presenting Teamproject software,an asynchronous Web Computer Supported Cooperative Work (CSCW) oriented toward the sharing and viewing of 3D data (CAD and FEA)based on Virtual Reality Modeling Language (VRML). Regarding the collaborative design and concurrent engineering approaches, thissoftware increases the information access and its availability to expert and non-expert users in a remote mode.The article deals with the benefits proposed by the use of Web technologies in mechanical design and structural analysis fields. It detailsthe software architecture of Teamproject. One of the added values offered by the new version of the Web CSCW is the translation of CADand FEA data into VRML format. It extends the 3D product data review to all the team members involved in a project. Indeed, the readingof the Java3D can be ensured by the most used web navigator (like Internet Explorer and Netscape) with the aid of a free plug-in. Tosummarize, the proposed Web CSCW provides a simple and efficient access to mechanical design and structural analysis data in a realcollaborative engineering approach.Key Words: collaborative design, CSCW, Web, FEA, CAD.

Abstract: The maintainability aspect of some complex products has a significant role during the life cycle; it is the design attribute determining the performance of various maintenance activities such as: inspection, diagnosis, repair, and replacement. If a product has poor maintainability, the maintenance activities which have to be performed on it during its life cycle are difficult, increasing the costs, and also the time required to accomplish the maintenance tasks. An early evaluation of maintainability during the design process may help the designers to make educated design choices, also from the maintenance point of view. In this article, we present a maintainability evaluation approach based on fuzzy logic; fuzzy linguistic variables are employed in order to represent and handle the design data available early in the design process. The main reason for employing fuzzy logic principles for maintainability evaluation is the imprecision and uncertainty generally characterizing the design data available at the beginning of the design process, when design specifications and requirements are subject to change and the description of the design is incomplete. The measure of the product maintainability or maintainability index might be expressed by a fuzzy numerical value computed as the weighted mean of the criteria values used for the evaluation.

Abstract: Computer-aided engineering (CAE) has been successfully used in mechanical industries such as automotive industries. CAE enables us to quantitatively evaluate the mechanical performances of products and to propose an effective way to improve their performances using optimization techniques without building physical prototypes. However, CAE tools are usually utilized not at the conceptual design phase, but at the evaluation phase following the detailed design phase. This is because current CAE tools require detailed design data that does not yet exist at the conceptual design phase, and such tools also inhibit the provision of useful design suggestions that, ideally, match the way of thinking and insight of design engineers. Thus, at present, no CAE tools exist that can assist the conceptual design decision making process of design engineers. On the other hand, conceptual design processes are of great significance when seeking to create innovative and high-performance products and to shorten their developme...

Abstract: Many companies report that they can attain a competitive product development advantage from strategic relationships with key suppliers, but even the successful relationships are not without their challenges. Industry has expressed a need for robust concurrent product development (CPD) practices to include supplier issues. Unfortunately, most of the practices currently available provide little to quantitatively analyze the product development process and to identify risk as a direct result of supplier interactions. This study develops metrics that characterize product development project risk that results from supplier interactions by using the concepts of degree of design customization (DoDC) and coupling ratio (CR). A correlation analysis based on HP LaserJet development projects demonstrates that the proposed metrics for DoDC and CR are good indicators of the likelihood of product development efficiency. Furthermore, there was enough evidence to use the interaction term, the CR multiplied by the DoDC, as a risk index. An important implication of using the coupling assessment as part of the project risk assessment is that the same process can address both project and product risks.

Abstract: Product development projects have evolved from the traditional sequential process into Concurrent Engineering (CE), which is known for its ability to reduce product development time and cost, while increasing quality. CE achieves this by overlapping the activities and executing them in parallel, which in return significantly increases iterations. The number of iterations largely depends on uncertainties in the process and learning occurs during the subsequent iterations. In this article, the effect of learning on CE projects is presented. First, the modeling of the activity structure, activity overlapping, and iterations are explained in a CE environment. Then a simulation model, which is developed by using the Arena Simulation package, is presented to test the effect of the learning process in CE projects. The simulation model developed is used to test five well-known learning theories through an extensive amount of data gathered from an industry-based project. The results suggest that all the learning m...

Abstract: Collaboration is becoming a new current paradigm for product manufacturing, as computer networks facilitate collaboration with partners located in widely distributed locations. Computer network technologies allow a large number of candidate partners to be examined for possible collaboration, so that the most suitable partner, or partners, can be selected from a broader, more diverse group than previously possible. In order to take best advantage of the collaboration paradigm, the precise method for selecting collaborative product development partners is an important technological point. Failed multicompany collaboration projects can do serious harm to the member companies on a number of fronts, in terms of financial cost, loss of prestige, loss of market share, and so on. The optimal collaboration partners should be selected from a group of candidates, so that production of new products can be achieved at a minimum cost, both financial and in terms of effort and expended resources. This paper proposes a decision supporting method for selecting an optimum collaborative product development partner from a group of potential partners. First, the effectiveness of collaborative product development and the need for a partner selection method is clarified. Next, a method for selecting the most suitable product development partner is constructed. Here, technologies that are required for developing the new product are classified into two groups: (1) technologies that have already been developed, and (2) technologies that must be newly developed. The proposed method first excludes unsuitable candidate partners, based on their achievement level concerning existing required technologies, and then selects the most suitable partner from the standpoint of technologies that must be newly developed. Finally, a case study is given to demonstrate the utility of the proposed method.

Abstract: Requirement engineering (RE) process is becoming a key factor for the success of complex one-of-a-kind products. The RE process is commonly viewed as an early system engineering phase with a major bearing on response time, quality, and cost. This study reports on the knowledge acquisition and sharing for requirement engineering (KARE), approach for requirement specification of one-of-a-kind complex systems. The approach provides a generic view of key RE processes clustered into three groups of activities - requirements elicitation, analysis, and negotiation. The process is supported by a set of knowledge functions aimed at facilitating the requirement engineers in matching customer requirements to product characteristics. At the analysis stage, the customer requirements are transformed into product requirements, which can be compared to existing company knowledge, for example, previous products, technology platforms, and production capabilities. The specified product requirements are then interactively ev...

Abstract: In this article, the dynamic Taguchi methodology is applied to the design of a barcode scanner. The concurrent engineering process involves a team of design and manufacturing engineers engaged in both hardware and software aspects of the product. The purpose of this experimental study is to determine the correlation between the outcomes of the conventional design and Taguchi optimization. The main contribution of this work in the design of scanners include: (a) application of the Taguchi methodology to yield an optimum design for scanning and comparing it to the analytical design, and (b) proving the existing opto-mechanical design to be optimum, within the signal processing capabilities. Experimental design using orthogonal arrays is established, and experiments of scanning on different barcode designs are conducted. The ideal function of the dynamic methodology is identified and the control and noise factors are chosen for the experimental design. The signal-to-noise (S/N) ratios and sensitivity are cal...

Abstract: Due to the complexity and uncertainties, the distributed design process requires dynamic collaborations among the heterogeneous systems and human interactions. In order to coordinate different system applications and humans, an event notification model is required. In this article, we propose a service event notification model based on grid service. The model takes advantage of the grid infrastructure and reduces the need for ad hoc development of middleware for supporting process coordination. In this model, an event notification server composed of a group of grid services can capture events from other grid services and generate process events. When an event occurs, event notification server decides to whom it should send the event according to an awareness model that keeps the states of the underlying coordination policies and business rules. The awareness model and the methodology for building an event notification system, together with the infrastructure of the notification server are presented in the article. An example in applying the model to a vehicle design project coordination scenario is presented to illustrate the potential application of the event notification model.

Abstract: Innovation has become a factor of competition. In order to increase the production of new knowledge, Concurrent Engineering (CE) could be applied to research activities by improving efficiency and reliability in the communication between the researchers. In the same way, research activities could also profit from approaches such as quality management and knowledge management. To this end, in this article, within a CE integrated team, research activities are analyzed in depth using a sociological study. Approaches harnessing the bibliographical work done by researchers are proposed - ANITA (ANnotation tool for Industrial TeAms) and MICA-Graph. Their associated communication tools are developed and undergo experimentation. The intention is to facilitate research activities by supporting information artifacts (textual and graphical such as sketches). These new and ergonomic groupware prototypes working on PC networks tend to be used to control two kinds of artifact: (1) Semi Structured Information (e.g., rep...

Abstract: Innovation has become a factor of competition. In order to increase the production of new knowledge, Concurrent Engineering (CE) could be applied to research activities by improving efficiency and reliability in the communication between the researchers. In the same way, research activities could also profit from approaches such as quality management and knowledge management. To this end, in this article, within a CE integrated team, research activities are analyzed in depth using a sociological study. Approaches harnessing the bibliographical work done by researchers are proposed - ANITA (ANnotation tool for Industrial TeAms) and MICA-Graph. Their associated communication tools are developed and undergo experimentation. The intention is to facilitate research activities by supporting information artifacts (textual and graphical such as sketches). These new and ergonomic groupware prototypes working on PC networks tend to be used to control two kinds of artifact: (1) Semi Structured Information (e.g., reports, etc.) thanks to the ANITA functions, that are based on the attribution of points of view and annotations on artifacts, and (2) Non Structured Information (such as mail, dialogues, etc.), thanks to the MICA-Graph approach, which is intended to support the exchange of messages that concern common resolution of research problems within CE-integrated teams and to capitalize relevant knowledge. It also provides facilities to structure and archive knowledge learned during this process owing to new methods of design sketch retrieval. For both approaches, the main feedback utilized involves manufacturing knowledge in the EADS industrial environment.

Abstract: A customer-oriented product designer must rely on many types of information, including customer-product requirements and design developments in the related fields. Concurrent engineering applications in product design problems will help designers to systematically consider relevant design information and make the most effective use of the time they devoted to the design process. Even though many new principles and approaches have been introduced to help designers to identify the relationship between customer requirements and design characteristics and solve complex design problems, they seldom focus on the generation of feasible design alternatives. This drawback greatly affects customer-oriented product design development.This research introduces a matrix approach that can efficiently generate feasible design alternatives for a specific set of customer requirements. The procedures developed for this matrix approach is based on a congruent matrix multiplication operator, component design strategy, and rel...

Abstract: Engineering design is a complex activity, and is heavily reliant on the know-how of engineering designers. Hence, capturing, storing, and reusing design information, design intent, and underlining design knowledge to support design activities is a key issue in engineering knowledge management. To meet the demand for engineering designers regarding functional feature and engineering specification-based knowledge resources, this study proposes a novel scheme for functional feature and engineering specification-based reference design retrieval using an integrated clustering approach for providing engineering designers with easy access to relevant reference design and associated knowledge. The research objectives can be achieved by performing the following five tasks: (i) designing a functional feature and engineering specification- based reference design retrieval process, (ii) developing a functional feature and engineering specification representation, (iii) investigating and integrating ART1 (adaptive resonance theory 1) neural network, GA (genetic algorithm), and fuzzy ART (fuzzy adaptive resonance theory) clustering techniques, and (iv) implementing a functional feature and engineering specification-based reference design retrieval mechanism and experimenting with an example. The retrieval process involves three steps: functional feature and engineering specification-based query, similar design case search and retrieval, and similar design case ranking. The techniques involved include: (i) a binary code-based representation for functional feature and an EXPRESS language-based representation for engineering specification, (ii) ART1 neural network and genetic algorithm for functional feature-based similar design case clustering, (iii) fuzzy ART for engineering specification-based similar design case clustering, (iv) similarity calculation for ranking similar design cases, and (v) a case-based representation for designed entities.

Abstract: Research for reduced lead time and cost in concurrent process development (CPD) becomes crucial in new work organizations. Today, the concurrent processes involve more and more activities and work groups which must be efficiently coordinated. In this article, the authors propose a framework for structuring concurrent activities in order to improve the global performance (lead time, workload, risks, etc.). Many research works aim at proposing methods for management and control of concurrent development activities, but these methods are often ‘isolated' and specific to an activity. There is no global solution that covers the entire development process and the set of related management and organizational activities. In this article, the authors used the SEI's (Software Engineering Institute) CMM (Capability Maturity Model) as a guideline to define an approach for the management and the control of a set of concurrent development activities. According to the CMM levels, the proposed approach is decomposed into four improvement steps that direct the organization's focus to manage its organizational development process. The first step applies basic project management methods to decompose and to schedule a process into several work groups. The second step addresses activities such as controlling the size of the obtained work groups, and characterizing each actor in a group. In the third step, a model based on the work transformation matrix (WTM) is proposed for the performance estimation of an organization. The last level aims at continually optimizing the organizational processes. For this purpose, models for sequential and parallel execution of processes are proposed and compared.

Abstract: The problem of object retrieval for design automation based on semi-semantic representation of objects of interest in images is addressed in this article. The concept of an ordered set of salient feature vectors (SFVs) is introduced to concisely describe multi-source image data in different application areas. A system architecture is presented which combines statistical learning modules with multi-scale morphological modeling and analysis of image contents. In the presented approach, the object retrieval is based on establishing correspondence between two ordered sets of SFVs: a query reference image (or concise description of the object) and a database image. On a higher level, new rules of association are established between the design objects, based on the extracted SFVs and their spatial relations in images. Experiments with different types of images confirmed the utility of the proposed content modeling and proved the adequacy of the extraction accuracy of the SFVs.

Abstract: Representation of the product/project information throughout the design life cycle is a critical aspect in engineering activities. The article begins with a discussion of the background research wherein the existing methodologies, which deal with product information representation, are reviewed. The article then proceeds to propose a new methodology for product management by presenting all the details of the system architecture. Product node (PN), which is introduced in this article, has a database-centric system at its core and an application built around it to support the various functions necessary to efficiently manage a distributed project environment. To aid the design life cycle, the system also enables distributed collaboration among people from different teams to support concurrent design activities. Effective management of product data using user-based control is also discussed. The detailed logic behind the system architecture and the practical implementation of the system are shown.

Abstract: In order to accurately cost the new product manufacture, and to assess a ‘what if ’ scenario in a rapid manner, requires an information system which can integrate the process design data for part manufacture and assembly with the organization’s business data. This article describes the development of such an information system, with a focus on the data model and the user interface design underpinning its operation, the benefits it has provided to the industry, and its usefulness as a teaching aid in the universities.

Abstract: This article presents an integrated approach to optimize cost while respecting the customer perception of a product using a modified Quality Function Deployment (QFD) method. This QFD method helps a design team to determine the effect of various design strategies for customer satisfaction. The new QFD method uses a two-phased approach for finding an optimum design strategy. During the first phase, the design team sets goals for customer perception for each customer attribute and relates them to those of its competitors (benchmarking); then, in the second phase, a goal-based model with a separated, mixed integer structure is used to minimize cost while respecting customer desires. The model defines fixed cost as a major improvement in design solutions such as changing parts, materials, or operational mechanisms. It also defines variable cost as a minor improvement in the current design solution. An illustrative example is given to demonstrate the use of the method, and a sensitivity analysis for budget lim...

Abstract: Taking into account the supplier involvement in the new product development (NPD), this article focuses on the synthesis evaluation, and selection of the part design scheme in part deployment process. The concepts of performance indicator (PI) and integrated performance indicators (IPI) are introduced to measure the performance of the part design scheme and product design scheme respectively. A two-layer fuzzy synthesis evaluation method is applied to assess the part design scheme in a supplier-involved new product development process. Combining the information of House of Quality (HoQ) and evaluation results of the part design scheme and taking into account the design budget, a 0–1 integer programming model is developed for selection of the parts combinatorial scheme in supplier-involved part deployment processes. A case study with a type of liquid crystal display (LCD) design in an Electronic Appliance Manufacturing Enterprise is also illustrated in the article.

Abstract: Engineering design is a knowledge-intensive process, including conceptual design, detailed design, engineering analysis, assembly design, process design, and performance evaluation. Each of these tasks involves various aspects of knowledge and experience. They are the most valuable sources for capitalizing enterprise knowledge and know-how on building enterprise memory, which may become part of enterprise assets. Therefore, capturing and representing product design information, design intents, and underlining design knowledge for later reuse is the basis of and one of the key tasks in engineering knowledge management.This study develops an approach for engineering knowledge refinement to facilitate engineering knowledge management. This approach is basically a refinement process that includes the steps of knowledge capture, knowledge representation and storage, and knowledge compilation. This study involves the development of a semantic graph for describing product-related information, design intent and k...

Abstract: Complex products or projects with long development times always involve multiple disciplines and a great deal of effort. Especially in concurrent engineering, the design needs to simultaneously consider various downstream activities throughout the entire product life cycle. To accomplish this, tasks in the concurrent engineering environment generally involve multifunctional teams in which team members from different functional departments interact in every phase of development tasks. However, as products become more complex, so do the design process and the project teams. This will inevitably degrade team performance when the team size becomes too large to handle. Moreover, to ensure a successful multifunctional team, it is also important to understand the characteristics of team members that affect team performance. Thus, an efficient multifunctional team can be established with all the right team members being assigned. The objective of this research is to develop an integrated methodological framework ...