A tool for the conceptual design of production and operations systems

This paper proposes a conceptual design tool, based upon inferential design theory. It has been specifically developed for the design of production and operations systems, but its use can be extended to other engineering areas, such as mechanical and structural systems. Inferential design theory and its foundation in the inferential theory of learning are briefly outlined. Both theories are based on the idea of using specialised knowledge operators in learning and design, termed knowledge transmutations and design knowledge transmutations respectively. The 24 transmutations existing in the two theories are outlined, and a further 12 design-specific transmutations are proposed. These have been developed as a result of our research. A conceptual design process is proposed, in which design knowledge transmutations are used. A software tool for design, CREDO, is also described and an example of its use in the generation of design concepts for an after-sales service facility is presented. The conclusions discuss the initial methodological experience of using CREDO to generate design concepts. They are based on the introductory use of CREDO at Technion in Israel for teaching purposes. Directions for further research are also provided.     

Computer tools for integrated conceptual design

This paper outlines the conceptual design process with reference to the integrated computer-aided design tool known as Schemebuilder, and the related work of the Lancaster University Engineering Design Centre. The aim of the Lancaster EDC is to provide highly integrated support for the rapid creation and evaluation of a wide range of outline design schemes. Particular attention is paid to the design of mechatronic systems and devices.     

A scheme for functional reasoning in conceptual design

An ideal functional reasoning environment should support designs of any nature, routine or innovative, at any level of detail, as well as through varying levels of detail. In this paper, three existing functional reasoning models are reviewed in this perspective. It has been found that none of these models support all of these requirements. It has been shown that a functional reasoning approach cannot guarantee the generation of solution concepts, which are combinations of known solutions, unless guided by the knowledge of existing solutions. A new model which can support design both across a level of detail and down through levels of detail has been proposed, which, using a divide and rule approach and using recursive problem redefinition while incorporating existing solutions, could support conceptual design. It is also shown that, although the generation of completely new solutions is not supported by the model, the model, when aided by a framework allowing a sustained progress of its knowledge base by transfer of knowledge from existing designs in the form of basic structures and rules of combination, could support generation of designs which otherwise would be considered unsupportable in a systematic way (innovative).     

The potential for mechanical design compilation

Significant potential exists for engineering design research to produce viable approaches to automatic compilation of mechanical systems.     

A multi-agent-based approach for conceptual design synthesis of multi-disciplinary systems

It is encouraged that designers should explore in wide multi-disciplinary solution spaces for finding novel and promising principle solutions to desired functions during conceptual design. However, due to lack of sufficient multi-disciplinary knowledge, it is often difficult for human designers to explore in wide multi-disciplinary solution spaces. Therefore, this paper proposes a multi-agent-based approach for assisting designers in achieving multi-disciplinary conceptual design synthesis. The roles of different kinds of designing agents are identified, and the collaborative mechanisms among these agents are also elaborated. The conceptual design test case of a solar toy demonstrates that the proposed multi-agent-based design synthesis approach, compared with our previous approach, can achieve higher efficiency and better robustness through collaborative conceptual design synthesis.     

A semi-analytic approach to robust design in the conceptual design phase

One of the most important contributions to quality engineering over the last decades is the concept of robust design and its accomplishment through the use of various experimental methods. However, the prerequisite for successful parameter design in terms of a robust solution principle is seldom discussed. Methods that explicitly aid robust design in the conceptual design phase exist but are few. This article forwards the suggestion to use the principles behind the error transmission formula as a semi-analytic method for evaluation of robustness of concept solutions, prior to entering Taguchi's parameter design stage.     

A heuristic-based approach to conceptual design

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.     

An approach to functional synthesis of solutions in mechanical conceptual design. Part III: Spatial configuration

These three papers describe an approach to the synthesis of solutions to a class of mechanical design problems; these involve transmission and transformation of mechanical forces and motion, and can be described by a set of inputs and outputs. The approach involves(1) identifying a set of primary functional elements and rules of combining them, and(2) developing appropriate representations and reasoning procedures for synthesizing solution concepts using these elements and their combination rules; these synthesis procedures can produce an exhaustive set of solution concepts, in terms of their topological as well as spatial configurations, to a given design problem.This paper (Part III) describes a constraint propagation procedure which, using a knowledge base of spatial information about a set of primary functional elements, can produce possible spatial configurations of solution concepts generated in Part II.     

机构特征挖掘与创新概念设计方法

传统机构设计方法过度仰赖设计者本身专业素养与创意构思,缺乏有系统地利用现有信息,基础回避设计层级中往往无法有效掌握技术的创意概念,导致陷入低阶设计修改的窠臼之中。若能运用专利分析挖掘出机构设计概念,从大量know-how的分析中获得功能设计的know-why,则能于专利中获取相关机构之设计精神。设计方法则导入系统化机构概念设计,提高设计层次,以挖掘出的大量信息为设计基础,汇整出机构设计规范,并将设计规范导入概念设计方法,获得可行机构设计。如此能充分运用现有机构获得创新机构设计,能更有效率且更能掌握机构设计内涵,对于设计者能有效地获得可行设计、避免设计产生雷同而浪费资源,并可缩短研发时程。     

Supporting conceptual design with multiple VR based interfaces

Conventional computer aided design (CAD) systems have not provided enough support for conceptual design partly due to the lack of natural and intuitive human-computer interaction. Currently emerging virtual reality (VR) based techniques offer new ways to overcome these obstacles. In this paper, new CAD user interfaces including two-handed operation, haptic interaction, stereoscopic display and auditory feedback are investigated. The contribution of this work is to develop a new direct, natural and intuitive interaction paradigm required to support conceptual design. This paradigm enables designers to take fuller advantage of their visual, auditory and tactile sensorial channels to create, view, touch, hold, manipulate and listen to computer-generated virtual models. This is done more easily and freely in a more realistic three-dimensional (3D) environment through convenient interface device operation. A new conceptual design system called the LUCID system that fully integrates and implements these VR-based innovative interfaces into one design application is presented. As an approach to the next generation of human-computer interfaces for use in the design activity, the LUCID system has shown particular human computer interface benefits to designers during conceptual design based on the outcome from the user evaluation test.     

The methodological basis for information systems design

The development of computer-based information systems has always been a complex task demanding high-level skills on the part of the designers. And yet there is still confusion about the meaning of design, and its associated skills, in this area. This paper addresses the ways in which methodological guidelines have been proposed over recent years, and attempts to evaluate their benefits and disadvantages. It draws conclusions about the future directions of design strategies for producing information systems.     

Behavioural representation and simulation of design concepts for systematic conceptual design of mechatronic systems using Petri Nets

The systematic representation of design concepts is an important requirement for computational support during the conceptual design stage within the process of product development. Behavioural simulation of design concepts is used as a systematic representation framework, and behavioural representation is based on modelling and simulating the behaviour of a design artefact at the conceptual level to perform an overall function, leading to behaviour-based conceptual design. The behaviour-based conceptual design approach is critical for mechatronic systems since they require synergistic integration starting from the initial conceptual design phase. The present study is focused on behavioural representation and simulation of design concepts via discrete event system specification formalism and Petri Nets so as to contribute to systematic conceptual design in mechatronic systems. The paper introduces a representation framework for the behaviour-based conceptual design of mechatronic systems and its implementation on five selected case studies, among laboratory-level educational robots. In addition to Petri Net modelling and computer simulations, the implementation also includes physical simulations of the intended operational behaviours for educational robots on a distributed physical structure called the ‘desktop design model’. In this paper, implementation on one of these case studies, namely the ‘frog robot’, is presented in detail.     

Supporting conceptual design with multiple VR based interfaces

Conventional computer aided design (CAD) systems have not provided enough support for conceptual design partly due to the lack of natural and intuitive human–computer interaction. Currently emerging virtual reality (VR) based techniques offer new ways to overcome these obstacles. In this paper, new CAD user interfaces including two-handed operation, haptic interaction, stereoscopic display and auditory feedback are investigated. The contribution of this work is to develop a new direct, natural and intuitive interaction paradigm required to support conceptual design. This paradigm enables designers to take fuller advantage of their visual, auditory and tactile sensorial channels to create, view, touch, hold, manipulate and listen to computer-generated virtual models. This is done more easily and freely in a more realistic three-dimensional (3D) environment through convenient interface device operation. A new conceptual design system called the LUCID system that fully integrates and implements these VR-based innovative interfaces into one design application is presented. As an approach to the next generation of human–computer interfaces for use in the design activity, the LUCID system has shown particular human computer interface benefits to designers during conceptual design based on the outcome from the user evaluation test.     

The cognitive basis of emergence: implications for design support

Emergent shapes play a significant role in the creative design process. Designers frequently visualize emergent shapes and structure their understanding of the design and their reasoning about it in terms of emergent entities and relations. In design research, effort has concentrated on developing computational models capable of representing emergent shapes. Much less attention has been paid to the cognitive processes that give rise to emergence. In cognitive science, however, emergence has been the subject of empirical study. It is suggested that both the study of perception and that of mental imagery can contribute to understanding the cognitive psychological basis of emergence and the nature of emergent shapes that arise. Relevant cognitive science research findings are reviewed in this paper. Based on these findings two main classes of emergence processes are developed. Their implications for the development of user-interactive computational models of emergent shapes are then discussed.     

Representation of function-form relationship for the conceptual design of stamped metal parts

Design representation of parts during conceptual design stage has been a challenging task because of the incompleteness of the information available. Traditional geometric design requires too much information on the geometric attributes, and does not consider the functionality of the part any more than that provided by individual features. Functional design in the form of verb, noun representation does not have adequate correlation with the geometric design. In this article, we propose a new form of the design representation of parts during conceptual design. The representation is calledsketching abstraction. In this representation, the discretionary geometry of the part that has functional relevance is captured using functional features, while the non-discretionary geometry is represented using a linkage mechanism. The functional features are related to the part function using data structures calledfunction-form matrices. The sketching abstraction is annotated with a set of primitives, and a grammar has been developed that parses the sketch to extract a set of canonical relationships between the functional features. These relationships can be used to extract part designs that are functionally similar but geometrically dissimilar. The sketching abstraction has a relationship with the solid model of the part as well. Thus we attempt to bridge the gap between function and form representations and provide the designer with a tool that can be used for generating design alternatives. We illustrate the theory developed in the domain of stamped metal parts.     

Expertise in engineering design

Most studies of designer behavior are limited to studies of novice or average-ability designers. We have studied two outstanding, expert designers, and are able to draw some parallels between their design strategies. We note that they both take a systemic view of the design situation, choose to frame their view of the problem in a challenging way, and draw upon first principles to guide both their overall concept and detailed design. Studying expert designers should enable us to identify the seeds of best practice. This should be useful in design practice and in education, for guiding the development of better-than-average designers.     

A cross-disciplinary technology transfer for search-based evolutionary computing: from engineering design to software engineering design

Although object-oriented conceptual software design is difficult to learn and perform, computational tool support for the conceptual software designer is limited. In conceptual engineering design, however, computational tools exploiting interactive evolutionary computation (EC) have shown significant utility. This article investigates the cross-disciplinary technology transfer of search-based EC from engineering design to software engineering design in an attempt to provide support for the conceptual software designer. Firstly, genetic operators inspired by genetic algorithms (GAs) and evolutionary programming are evaluated for their effectiveness against a conceptual software design representation using structural cohesion as an objective fitness function. Building on this evaluation, a multi-objective GA inspired by a non-dominated Pareto sorting approach is investigated for an industrial-scale conceptual design problem. Results obtained reveal a mass of interesting and useful conceptual software design solution variants of equivalent optimality—a typical characteristic of successful multi-objective evolutionary search techniques employed in conceptual engineering design. The mass of software design solution variants produced suggests that transferring search-based technology across disciplines has significant potential to provide computationally intelligent tool support for the conceptual software designer.     

Shear wall layout optimization for conceptual design of tall buildings

Efficient methods for incorporating engineering experience into the intelligent generation and optimization of shear wall structures are lacking, hindering intelligent design performance assessment and enhancement. This study introduces an assessment method used in the intelligent design and optimization of shear wall structures that effectively combines mechanical analysis and formulaic encoding of empirical rules. First, the critical information about the structure was extracted through data structuring. Second, an empirical rule assessment method was developed based on the engineer's experience and design standards to complete a preliminary assessment and screening of the structure. Subsequently, an assessment method based on mechanical performance and material consumption was used to compare different structural schemes comprehensively. Finally, the assessment effectiveness was demonstrated using a typical case. Compared to traditional assessment methods, the proposed method is more comprehensive and significantly more efficient, promoting the intelligent transformation of structural design.