Showing papers on "Conceptual design published in 2009"

Impact of CAD tools on creative problem solving in engineering design

Abstract: This paper presents the results of a survey of CAD users that examined the ways in which their computational environment may influence their ability to design creatively. This extensive online survey builds upon the findings of an earlier observational case study of the use of computer tools by a small engineering team. The case study was conducted during the conceptual and detailed stages of the design of a first-to-world product. Four mechanisms by which CAD tools may influence the creative problem solving process were investigated: enhanced visualisation and communication, circumscribed thinking, premature design fixation and bounded ideation. The prevalence of these mechanisms was examined via a series of questions that probed the user's mode of working, attitudes, and responses to hypothetical situations. The survey showed good support for the first three mechanisms and moderate support for the fourth. The results have important implications for both the users and designers of CAD tools.

A Proposal for a Formal Definition of the Design Concept

Abstract: A clear and unambiguous definition of the design concept would be use- ful for developing a cumulative tradition for research on design In this article we suggest a formal definition of the concept design and propose a conceptual model linking concepts related to design projects The definition of design incorporates seven elements: agent, object, environment, goals, primitives, requirements and con- straints The design project conceptual model is based on the view that projects are temporal trajectories of work systems that include human agents who work to design systems for stakeholders, and use resources and tools to accomplish this task We demonstrate how these two conceptualizations can be useful by showing that 1) the definition of design can be used to classify design knowledge and 2) the conceptual model can be used to classify design approaches

Modeling design objects in CAD system for Service/Product Engineering

Abstract: This paper proposes a new type of service CAD system utilized in Service/Product Engineering (SPE), a much-needed and novel engineering discipline within the background of servicification. In this research a design-object model was defined, and a prototype named Service Explorer was implemented. The model represents critical concepts such as value, costs, functions either of products or of service activities, and entities. Through its application to business cases such as selling washing machines, providing pay-per-wash service, and cleaning washing machines, the Service Explorer was proven to support designers as they describe and operate design objects. In the future we expect that the Service Explorer can help designers with generating new ideas.

The risk in early design method

Abstract: Risk assessments are necessary to anticipate and prevent accidents from occurring or repeating. Current probabilistic risk assessment methods require mature design proposals to analyse. Since product safety and reliability are affected the most by decisions made during the early design phases, a risk assessment that can be performed with less mature data during these design phases is needed. This study focuses specifically on the relationship between function and risk in early design by presenting a mathematical mapping from product function to risk assessments that can be used in the conceptual design phase. An investigation of a spacecraft orientation subsystem is used to demonstrate the mappings. The results from the study and its spacecraft application yield a preliminary risk assessment method that can be used to identify and assess risks as early as the conceptual phase of design. The preliminary risk assessment presented in this paper is a tool that will aid designers by identifying risks as well a...

Multi-attribute utility analysis in set-based conceptual design

Abstract: During conceptual design, engineers deal with incomplete product descriptions called design concepts. Engineers must compare these concepts in order to move towards the more desirable designs. However, comparisons are difficult because a single concept associates with numerous possible final design specifications, and any meaningful comparison of concepts must consider this range of possibilities. Consequently, the performance of a concept can only be characterized imprecisely. While standard multi-attribute utility theory is an accepted framework for making preference-based decisions between precisely characterized alternatives, it does not directly accommodate the analysis of imprecisely characterized alternatives. By extending uncertainty representations to model imprecision explicitly, it is possible to apply the principles of utility theory to such problems. However, this can lead to situations of indeterminacy, meaning that the decision maker is unable to identify a single concept as the most preferred. Under a set-based perspective and approach to design, a designer can work towards a single solution systematically despite indecision arising from imprecise characterizations of design concepts. Existing work in set-based design primarily focuses on feasibility conditions and single-attribute objectives, which are insufficient for most design problems. In this article, we combine the framework of multi-attribute utility theory, the perspective of set-based design, and the explicit mathematical representation of imprecision into a single approach to conceptual design. Each of the component theories is discussed, and their combined application developed. The approach is illustrated using the conceptual design of a fixed-ratio power transmission as an example. Additionally, important directions for future research are identified, with a particular focus on the process of modeling abstract design concepts.

Thoughts on Interaction Design

Abstract: Interaction Designers-whether practicing as Usability Engineers, Visual Interface Designers, or Information Architects-attempt to understand and shape human behavior in order to design products that are at once usable, useful, and desirable. Although the value of design is now recognized as essential to product development, the field is often misunderstood by managers and other team members, who don't understand a designer's role in a team. This can cause inefficient and ineffective products.Thoughts on Interaction Design gives individuals engaged in this profession the dialogue to justify their work to other stakeholders. It provides a framework upon which to build intellectual discourse, and it substantiates the rigorous and unique nature of interaction design work. Ultimately, the text exists to provide a definition that encompasses the intellectual facets of the field, the conceptual underpinnings of interaction design as a legitimate human-centered field, and the particular methods used by practitioners in their day to day experiences. *First book to provide a solid definition and framework for the booming field of interaction design, finally giving designers the justification needed to prove their essential role on every development team*Provides designers with tools they need to operate effectively in the workplace without compromising their goals: making useable, useful, and desirable products*Outlines process, theory, practice, and challenges of interaction design - intertwined with real world stories from a variety of perspectives

Beyond design thinking: Design-as-practice and designs-in-practice

Abstract: Recent publications by scholars, practitioners and government bodies claim that design, or rather design thinking, has the power to stimulate or drive innovation and transform organizations and even societies. But the term “design thinking” is confused and the literature on which it is based is contradictory. This paper contributes to understanding design activity and its effects by reviewing literature and identifying problems with the concept drawing on theories of practice in sociology, science and technology studies and organization studies. It proposes an alternative way of conceiving of design activity, without privileging the work done by designers, by attending to the practices of others involved in constituting design outcomes. Introducing a pair of concepts ‐ design-as-practice and designs-in-practice ‐ to replace design thinking solves a number of problems facing researchers in design and management. The paper’s contribution is to make an explicit link between design and social science in order to advance understanding about designers’ work and value creation.

Application of analytical hierarchy process in the design concept selection of automotive composite bumper beam during the conceptual design stage

Abstract: Selection of design concepts is an area of design research that has been under considerable interest over the years. The level of success of product designs achieved depends significantly on the initial concept at the conceptual design stage. Inappropriate decision making during design concepts selection at the conceptual design stage can cause the product to be redesigned or remanufactured. To overcome such problem, this paper proposed a concept selection model called concurrent design concept selection and materials selection (CDCSMS) to assist designers in selecting the most appropriate design concepts and materials for automotive composite components at the conceptual design stage using analytical hierarchy process (AHP). To illustrate the proposed model, 8 design concepts of automotive composite bumper beam are considered and the most appropriate one is determined by using the analytical hierarchy process (AHP). The final decision was carried out by performing the sensitivity analysis in order to study the effect of the different factors on deciding the best decision option. Key words: Analytical hierarchy process (AHP), design concept selection, conceptual design stage, automotive bumper beam.

Efficiency and availability driven R&D issues for DEMO

Abstract: DEMO is the main step foreseen after ITER to demonstrate the technological and commercial viability of a fusion power plant. DEMO R&D requirements are usually identified on the basis of the functions expected from each individual system. An approach based on the analysis of overall plant functional requirements sheds new light on R&D needs. The analysis presented here focuses on two overall functional requirements, efficiency and availability. The results of this analysis are presented here putting emphasis on systems not sufficiently considered up to now, e.g. the heating and current drive systems, while more commonly addressed systems such as tritium breeding blankets are not discussed in detail. It is also concluded that an overall functional analysis should be adopted very early in the DEMO conceptual design studies in order to provide a fully integrated approach, which is an absolute requirement to ensure that the ambitious goals of this device will be ultimately met.

Design as integration of axiomatic design and design structure matrix

Abstract: Axiomatic design and design structure matrix (DSM) are two popular design methods at the moment, while most related researches only apply the basic ideas of axiomatic design or DSM to some use cases. This paper analyses the disadvantages of both axiomatic design and DSM. The axiomatic design method guides the designer finding suitable design parameters to meet the needs of function requirements. But axiomatic design cannot support the designer to know the interactions amongst the design parameters, including geometry, spatial layout, interfaces (e.g. logical and physical connectivity), which will decide the quality of the design. DSM has the advantages at recording and analysing the interaction relationship between existing product elements. However, at the conceptual design stage or for a new product that has never been designed before, it is difficult to make the DSM. After deep investigations, it has been found that there are strong complementarities between axiomatic design and DSM, and integration of both sides is advocated for better-quality design. The main outcome of this work is the formal interpretation of the integration logic between axiomatic design and DSM. Under such integration context, the conceptual design process can be seen as a recursive interaction of axiomatic design's design matrix (DM) and corresponding DSM. In this way, axiomatic design and DSM can benefit from each other. A computer-aided conceptual design system has been developed to realize the proposed integration model of axiomatic design and DSM.

Creative conceptual design: Extending the scope by infused design

Abstract: Many methods that support human creativity by manual or computational means have been proposed in the past. They rely on the assumption that following a certain process of reasoning might lead to generating ideas considered creative. We start by defining creativity as a capability that enables the creation of systems that are patentable. We review the state-of-the-art of creative conceptual design and organize it with a framework. Subsequently, we present a method called infused design that guarantees the generation of design solutions by transforming systems and methods from remote disciplines. In many cases, these solutions would be deemed creative. Finding these systems and their transformations is done through a process based on the underlying discrete mathematical representation. This process is partially supported by a computer tool. We describe the method of infused design and illustrate its operation through part of the results achieved until now, including designing a new active torque amplifier system. We further demonstrate its benefits through other examples. We discuss the relation of infused design with other creativity or design methods and conclude with future developments of the method. ''A well-directed imagination is the source of great deeds.'' Chinese proverb

A computerized optimization framework for the morphological matrix applied to aircraft conceptual design

Abstract: This paper presents a formal mathematical framework for the use of the morphological matrix in a computerized conceptual design framework. Within the presented framework, the matrix is quantified so that each solution principle is associated with a set of characteristics such as weight, cost, performance, etc. Selection of individual solutions is modeled with decision variables and an optimization problem is formulated. The applications are the conceptual design of subsystems for an Unmanned Aerial Vehicle and an aircraft fuel transfer system. Both the system models and the mathematical framework are implemented in MS Excel.

A Computational Product Model for Conceptual Design Using SysML

Abstract: The importance of the concept development phase in product development is contradictory to the level and amount of current computer-based support for it, especially with regards to mechanical design. Paper-based methods for conceptual design offer a far greater level of maturity and familiarity than current computational methods. Engineers usually work with software designed to address only a single stage of the concept design phase, such as requirements management tools. Integration with software covering other stages, e.g. functional modeling, is generally poor. Using the requirements for concept models outlined in the VDI 2221 guideline for systematic product development as a starting point, the authors propose an integrated product model constructed using the Systems Modeling Language (SysML) that moves beyond geometry to integrate all necessary aspects for conceptual design. These include requirements, functions and function structures, working principles and their structures as well as physical effects. In order to explore the applicability of SysML for mechanical design, a case study on the design of a passenger car’s luggage compartment cover is presented. The case study shows that many different SysML diagram types are suitable for formal modeling in mechanical concept design, though they were originally defined for software and control system development. It is then proposed that the creation and use of libraries defining generic as well as more complicated templates raises efficiency in modeling. The use of diagrams and their semantics for conceptual modeling make SysML a strong candidate for integrated product modeling of mechanical as well as mechatronic systems.Copyright © 2009 by ASME

Developing a service knowledge reuse framework for engineering design

Abstract: The manufacturing industry is shifting its emphasis from a traditional supplier of products to a supplier of increasingly integrated products and services, or product-service systems (PSSs). The new paradigm of PSS requires new design methodologies and supporting tools for the effective design and delivery of these enhanced services and integrated PSSs. A case study has been carried out to identify and classify service knowledge applied in practice, both in the service operation and in product design. This paper describes the service issues and service knowledge that has an impact on product design. An initial attempt is made to describe the role of service knowledge in design and also to describe in detail how to apply service knowledge in the conceptual design stage based on an existing requirements management framework modified for this context. This research makes an important contribution to the developing knowledge and information requirements of PSS design.

Using an engineering change methodology to support conceptual design

Abstract: Most designs are modifications from previous products and lessons learned from earlier designs can be beneficial when developing new products. This paper introduces a support tool for the conceptual design phase, which is based on connectivity models of past designs and allows designers to assess the risk of change spreading between components and facilitates a visual analysis of these change models. Based on the example of a new generation of diesel engine design, this paper shows how the ability to predict change propagation can guide designers through conceptual design allowing them to analyse design alternatives and foresee potential problems arising from the product architecture.

Management of Cross-Domain Model Consistency during the Development of Advanced Mechatronic Systems

Abstract: The development of mechatronic systems demands the close collaboration of engineers from different domains. In the course of the development, this leads to the creation of a number of separate, but interdependent models which capture the domain-specific system aspects. Without harmonizing the domain-specific development processes, inconsistencies between the domain-specific models are likely to occur. If these inconsistencies remain undetected, the system integration will fail, which is leading to increased development time and costs. As a first step to prevent these problems, we propose a cross-domain system specification in the early conceptual design phase. Furthermore, as the novel contribution of this paper, we show how model transformation techniques can be employed to, firstly, derive initial domain-specific models for the subsequent domain-specific development and, secondly, to propagate domain-spanning relevant changes that may occur between those models. We show how the domain-spanning relevance of changes may be detected automatically and we discuss where expert decisions are indispensable. We implemented the approach in our development environment.

A heuristic-based approach to conceptual design

Abstract: In the inherently large space of design, explicating all possible concept variants—to avoid leaving out potential concepts—is astronomically costly, if at all possible. A strategy that can assist designers in exploring and ascertaining design solutions within this vast space is therefore crucial. This work adapts a general best first heuristic algorithm for applications on conceptual design problems. The algorithm is tailored to operate on a model of conceptual design postulated in this paper. The propositions are established by an ordered series of formal definitions and mathematical assertions, which characterizes the complete theoretical model. Via a simple design case study, this product conceptualization approach is demonstrated to strategically guide designers in the exploration of design concepts.

A Component Taxonomy as a Framework for Computational Design Synthesis

Abstract: In this paper, we present our findings on the development of a taxonomy for electromechanical components. In building this taxonomy, we have two main objectives: First, we strive to establish a framework for future computational tools that archive, search, or reuse component knowledge during the conceptual phase of design. Second, we aim to define a standard vocabulary that derives uniformity and consistency in the representation of electromechanical component space. Through both empirically dissecting existing products and defining categories based on functional analysis, we defined 135 generic component types. The use and necessity of the resulting taxonomy by a suite of computational design tools are illustrated in two applications of conceptual design.

The Art of Design: A Design Methodology

Abstract: [ILLUSTRATION OMITTED] It is well known that when you do anything, unless you understand its actual circumstances, its nature and its relations to other things, you will not know the laws governing it, or know how to do it, or be able to do it well. --Mao Tse Tung (1) HE PURPOSE OF THIS ARTICLE is to describe a methodology for design to account for what military designers do and how they do it when they are confronted with a complex situation. This description is a snapshot of an evolving approach that encourages critical thought, innovation, and creativity, and as such should not be taken as prescriptive or limiting. Rather, the intent is to document current best practices to provide sufficient design guidelines for successful planning to occur. This narrative describes how design informs planning and action. It then introduces the prerequisite theory needed to explain the art of design and provides a brief overview of an approach for developing a comprehensive response to a complex situation. America's International Technology Education Association defines design as an iterative decision-making process that produces plans by which resources are converted into products or systems that meet human needs and wants or solve problems. According to this definition, design is iterative, meaning it does not follow a linear sequence, and it does not terminate just because a solution has been developed. Because design can be used to produce systems, not just products, and is applicable to the spectrum of human needs and wants, design is both extremely general and ubiquitous in nature. The definition implies that design is focused on solving problems, and as such requires intervention, not just understanding. Whereas scientists describe how the world is, designers suggest how it might be. (2) It follows that design is a central activity for the military profession whenever it allocates resources to solve problems, which is to say design is always a core component of operations. As a professional intellectual activity, design requires both practical experience and theoretical support. Mastery of a profession can only come through mentoring, coaching, and experiential learning as a member of a community of practice, in addition to the appropriate academic development of a leader throughout the course of a career. The School of Advanced Military Studies (SAMS) has been fostering an experiential learning environment to create a holistic approach for the art of design. Our approach to educating by design is described in a companion article, "Educating by Design," in this issue. In addition to studying military theory, history, and doctrine, SAMS students learn through large-scale exercises and interactive class activities; evaluate design theory across multiple professions; participate in critical discursive reviews; and contribute to discourse by completing a research monograph that may focus on any aspect of their education. At SAMS, we believe the art of design is a way of thinking more than it is a theory, process, or product. Even though the design of military operations is informed by design practices of other professions, it is essential to account for the unique situations encountered in the extremes of conflict environments. In no other context does the influence of the adversary feature so centrally in design. Combat operations must account for the role of chance and friction, which Clausewitz noted makes even the simplest things in war difficult. (3) A philosophy of design tailored to military operations, called systemic operational design, has been developed within a largely verbal tradition by retired Israeli Brigadier General Shimon Naveh. (4) A recent article in Military Review by retired U.S. Army Brigadier General Huba Wass de Czege explains the relevance of design to the U.S. Army. (5) Since 2005, SAMS has been closely involved with evaluating these concepts as part of its holistic approach to the art of design. …

On the Application of Uncertainty and Sensitivity Analysis with Abstract Building Performance Simulation Tools

Abstract: Building Performance Simulation (BPS) is a powerful measure to educate the building design process. However, its use in practice is too large extents limited to the detailed design stage dedicated to the code compliance analysis of worked out design proposals. BPS is not much used to support the conceptual design stage. To date BPS - tools are regarded as pure analysis tools, which do not provide design information. It is hypothesized that, when integrating uncertainty analysis techniques to existing BPS - tools, following an incremental research approach, valuable design information can be provided. The paper gives an update on the process to extend the capabilities of a tool specifically developed to support the conceptual design stage about uncertainty assessment. The resulting prototype should be capable of providing information about the variation of specific building performance metrics (simulation output) based on the propagated uncertainties of the building specification (simulation input). The results also indicate the degree of impact, sensitivity, of the building specification parameters on the variation of the performance metrics as a result of their uncertainty. This paper describes an approach to add extra-capabilities to legacy simulation tools and presents a comparison of uncertainties and sensitivities calculated with one detailed design analysis tool, IES, and one conceptual design analysis tool, LEA. The main focus was herby the representation of material properties and their impact on the performance uncertainty of the building concept.

Product Attribute Function Deployment (PAFD) for Decision-Based Conceptual Design

Abstract: The critical product planning phase, early in the product development cycle, requires a design tool to establish engineering priorities, select the preferred design concept, and set target levels of engineering performance while considering the needs of both the consumer and producer. The quality function deployment (QFD) method was developed as a design process tool to translate customer needs into engineering characteristics; however, limitations have been identified in using the QFD method for product planning. In this paper, a new design tool called product attribute function deployment (PAFD), based on the principles of decision-based design (DBD), is introduced as a decision-theoretic, enterprise-level process tool to guide the conceptual design phase. The PAFD method extends the qualitative matrix principles of QFD while utilizing the quantitative decision-making processes of DBD. The PAFD method is built upon established methods in engineering, marketing, and decision analysis to eliminate the need for the user ratings and rankings of performance, priority, and attribute coupling in the QFD method. The differences between the QFD and the PAFD processes are compared and contrasted, and the conceptual design of an automotive manifold absolute pressure sensor is used as a case study to demonstrate the features and benefits of the PAFD method.