Theory construction in design research: criteria: approaches, and methods

Design involves solving problems, creating something new, or transforming less desirable situations to preferred situations. To do this, designers must know how things work and why. Understanding how things work and why requires us to analyze and explain. This is the purpose of theory. The article outlines a framework for theory construction in design. This framework will clarify the meaning of theory and theorizing. It will explain the nature and uses of theory as a general concept. It will propose necessary and sufficient conditions for theory construction in design. Finally, it will outline potential areas for future inquiry in design theory.     

基于概念设计的三维包装创意设计系统的技术和实现

本文介绍了一种基于概念设计的三维包装创意设计系统 .该系统具有常规包装创意设计系统的各项功能 ,同时支持概念设计中的在无特征无数字约束的状态下用鼠标拖动定性建模修改 ,能够更好地协助设计师进行创意构思     

Unexpected discoveries and S-invention of design requirements: important vehicles for a design process

Designers, during a conceptual design process, do not just synthesize solutions that satisfy initially given requirements, but also invent design issues or requirements that capture important aspects of the given problem. How do they do this? What becomes the impetus for the invention of important issues or requirements? So-called ‘unexpected discoveries', the acts of attending to visuo-spatial features in sketches which were not intended when they were drawn, are believed to contribute to it. The purpose of the present research is to verify this hypothesis. Analysing the cognitive processes of a practising architect in a design session, we found that in about a half of his entire design process there were bi-directional relations between unexpected discoveries and the invention of issues or requirements. Not only did unexpected discoveries become the driving force for the invention of issues or requirements, but also the occurrence of invention, in turn, tended to cause new unexpected discoveries. This has provided empirical evidence for two anecdotal views of designing. First, designing is a situated act; designers invent design issues or requirements in a way situated in the environment in which they design. We call inventions of this sort situated-invention (S-invention). Secondly, a design process progresses in such a way that the problem-space and the solution-space co-evolve. Further, this has brought a pedagogical implication as well as an insight about an important aspect of learning by experience in design.     

基于系统工程过程的维修性设计要求生成过程研究

维修性设计要求的生成是维修性工作的一个重要组成部分,然而目前还没有有效的方法和过程支持该项工作的开展.借鉴系统工程过程的基本步骤,结合产品的一般研制程序,提出维修性设计要求的一体化生成过程,该生成过程包括维修方案的生成、维修性指标的确定与分配、维修性设计要求的生成三个主要工作,并对各项工作过程进行了详细的阐述.     

TOC构造过程模型驱动产品创新设计

简要分析了产品冲突问题的约束理论(theory of constraints,TOC)思维流程,介绍了发明问题解决理论(theory of inventive problem solving,TRIZ)创新设计过程。描述了TOC中5个逻辑图表及其相互之间的关系。提出一种将TRIZ与TOC相结合的产品冲突问题解决过程构造模型的设计方法,利用所构造的产品当前实现树、逻辑图表和TRIZ的矛盾冲突解决矩阵来解决产品冲突问题。实例证明TRIZ与TOC相结合的方法用于驱动产品创新设计是切实可行的。     

Manufacturing process selection in engineering design. Part 1: the role of process selection

Whilst material selection methods are becoming mature, the selection of processes has been neglected — particularly after the preliminary design stages. This paper presents a view of current approaches to selection issues in engineering design with particular reference to process selection techniques. The need is highlighted for more focused selection techniques once a manufacturing task has been identified. A new methodology to aid the creation of task-based process selection procedures is outlined in Part 2 (A.M. Lovatt, H.R. Shercliff, J. Mater. Des., 19 (1998) 217–230).     

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.     

A model of composite laminated Reddy plate of the global-local theory based on new modified couple-stress theory

In this article, based on the global-local theory, a model for a composite laminated Reddy plate of new modified couple-stress theory is developed for the first time. This model satisfies free surface conditions and the geometric and stresses continuity conditions at interfaces. Differing from existing modified couple-stress theory, an anisotropic constitutive relation is suggested. There is only one micro material characteristic length constant in each layer of the composite laminated plate. Principle of virtual work is employed to derive the equilibrium equations and the corresponding boundary conditions. With the example of a cross-ply simple-supported Reddy plate subjected to the bending load q₀ = sin?(πx/L)sin?(πy/L), the transverse shear stresses at interfaces are addressed. Additionally, the numerical results show that the present plate model can capture the scale effect, especially the scale effect of the transverse shear stresses at interfaces of the composite laminated plate.     

QFD与D-S结合的维修性设计评估方法研究

 分析了维修性设计评估方法的不足,提出了基于需求分析的质量功能配置（quality function deployment, QFD）与证据理论（D-S theory）相结合的评估方法.该方法能够紧密反映军方需求,综合利用了QFD对需求分析和D-S对不确定性处理的优势.以图表的形式反映整个评估过程,具有一定的工程实用特性．     

Feature-based metal stamping part and process design. Part II: stamping process planning

In metal stamping development, stamping process planning plays quite an important role for the related die design. As mentioned in Part-I [Feature-based metal stamping part and process design. Part 1: stampability evaluation, 2007, 45, 2673–2695], the feature can encapsulate comprehensive engineering information; this paper proposes to realize stamping process planning based on feature mapping. A feature mapping system, between a stamping design feature space and a stamping process feature space, has been presented. The inherent mechanism of such feature mapping has been investigated with formal representations. The substance of feature mapping is the processing of related knowledge and information. Mapping rules are established to generate the stamping operation and stamping direction. Four mapping manners (direct mapping, conjugate mapping, syncretic mapping, and sequential mapping) are presented for generating the form of process feature, through geometrical information transformation from design features. Meanwhile, considering a stamping process plan as an ordered tree, this paper has introduced how to build a stamping process plan through organizing the stamping operations mapped from design features, and an illustrative example is demonstrated.     

Feature-based metal stamping part and process design. Part I: stampability evaluation

It is essential to devise a representation scheme for the metal stamping part design which allows the designer to capture and reason the design information, and ultimately, to take various considerations into account and make evaluation decisions. In our research, the feature-based approach is used to represent the metal stamping part, and feature-based metal stamping part and process design has been studied and presented in a two-part paper. This is the first of a two-part paper focusing on stampability evaluation. In Part II a feature-based stamping process planning approach is investigated. This paper presents a feature- and knowledge-based stampability evaluation system. Tasks of this research include identification of the aims, criteria, and procedure of stampability evaluation, as well as the formalization of the stampability evaluation knowledge. Stampability evaluation is classified into stampability verification and stampability measurement. Stampability verification is used to determine whether a part design is stampable or not. Stampability measurement can be employed to select a best design from stampable candidate designs. Based on the stamping design feature definition, a stampability-coding scheme with incorporated knowledge has been developed to enable comprehensive stampability evaluation. Finally, a case study demonstrates the feasibility of such stampability evaluation system.     

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.