A distributed multi-agent environment for product design and manufacturing planning

This paper describes a multi-agent approach to the integration of product design, manufacturability analysis, and process planning in a distributed manner. The objective is to develop a distributed concurrent engineering system to allow geographically dispersed entities to work cooperatively towards overall system goals. In the paper, an agent-based concurrent engineering system concerning product design and manufacturing planning, and its fundamental framework and functions are presented. The proposed model considers constraints and requirements from the different product development cycles in the early development phases and fully supports the concept of design-for-manufacturability. This methodology uses conflict resolution (CR) techniques and design-improvement suggestions to refine the initial product design. The model comprises a facilitator agent, a console agent and six service agents. Each service agent is used to model different product development phases, and the console agent acts as an interacting interface between designers and the system, while the facilitator is responsible for the decomposition and dispatch of tasks, and resolving conflicts of poor designs. A prototype system for part design, manufacturability analysis, and process planning has been implemented. The performance of the prototype system shows that it could be extended to include other service agents, such as assemblability analysis, to become a comprehensive distributed concurrent engineering system for geographically dispersed customers and suppliers.     

DFQM - an approach for improving the quality of assembled products

In this paper we introduce first the concept of quality manufacturability (QM), and second a new methodology that focuses exclusively on evaluating a design from a quality perspective. We label this new approach as Design for Quality Manufacturability (or DFQM). The QM of a design is defined as the likelihood that defects will occur during its manufacture. Some designs are more likely than others to have a lower production yield rate. The reason for this is that in any production facility there is an inherent defect occurrence process. This relationship between the defect occurrence process and the design is the basis for QM. DFQM enables product designers to evaluate and improve the QM of a design before prototype production. The key elements of DFQM are classes of defects, specific defects, influencing factors, factor variables, and error catalyst. A standard nomenclature for describing the specific defects and measuring the associated influencing factors is presented. The output of the DFQM method is the QM-Index matrix, which indicates the quality manufacturability of each part in the assembly, in terms of each class of defects. The concept of error catalysts and the derivation of the QM-Index matrix are presented. An illustrative example is included. The DFQM method is presently limited to assembly processes.     

基于案例的文化创意产品设计方法研究

针对文化产品的造型设计,将与产品造型相关的设计元素细分为功能、行为、文化、情感和构造法五个方面,结合基于案例的设计(case-based design,CBD)技术、遗传算法以及形状文法知识,建立文化创意产品设计概念原型系统并对文化创意产品进行引导设计。提出产品造型相关设计元素多目标优化模型,对用户需求进行匹配操作。提出文化产品造型设计方法模型,结合产品基因树交叉操作与形状文法知识,将现代类产品与文化器物类产品的设计元素进行交叉重组。通过对产品造型相关设计元素进行深入研究,并在文化创意产品设计概念原型系统中融入基于案例的设计技术、遗传算法和形状文法的知识,辅助设计师对文化产品进行创意设计。以小音箱为例,验证了该方法的可行性,为文化产品设计提供了一种有效方法。     

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.     

A methodology of integrating affective design with defining engineering specifications for product design

Affective design and the determination of engineering specifications are commonly conducted separately in early product design stage. Generally, designers and engineers are required to determine the settings of design attributes (for affective design) and engineering requirements (for engineering design), respectively, for new products. Some design attributes and some engineering requirements could be common. However, the settings of the design attributes and engineering requirements could be different because of the separation of the two processes. In previous studies, a methodology that considers the determination of the settings of the design attributes and engineering requirements simultaneously was not found. To bridge this gap, a methodology for considering affective design and the determination of engineering specifications of a new product simultaneously is proposed. The proposed methodology mainly involves generation of customer satisfaction models, formulation of a multi-objective optimisation model and its solving using a chaos-based NSGA-II. To illustrate and validate the proposed methodology, a case study of mobile phone design was conducted. A validation test was conducted and the test results showed that the customer satisfaction values obtained based on the proposed methodology were higher than those obtained based on the combined standalone quality function deployment and standalone affective design approach.     

A guided search genetic algorithm using mined rules for optimal affective product design

Affective design is an important aspect of new product development, especially for consumer products, to achieve a competitive edge in the marketplace. It can help companies to develop new products that can better satisfy the emotional needs of customers. However, product designers usually encounter difficulties in determining the optimal settings of the design attributes for affective design. In this article, a novel guided search genetic algorithm (GA) approach is proposed to determine the optimal design attribute settings for affective design. The optimization model formulated based on the proposed approach applied constraints and guided search operators, which were formulated based on mined rules, to guide the GA search and to achieve desirable solutions. A case study on the affective design of mobile phones was conducted to illustrate the proposed approach and validate its effectiveness. Validation tests were conducted, and the results show that the guided search GA approach outperforms the GA approach without the guided search strategy in terms of GA convergence and computational time. In addition, the guided search optimization model is capable of improving GA to generate good solutions for affective design.     

情景与FBS在产品创新设计中的应用

目的综合产品的情景设计和FBS模型优势,探索更有效的产品创新设计方法与技术。方法在分析情景组成元素的基础上,提出了情景构建的3个层次和未来情景构建过程框架,通过构建情景的FBS模型和情景类比模型,建立情景中各元素之间的关系,进而发掘设计空间。结合"柿饼成形"未来情景的构建说明该创新设计方法的有效性。结论对于传统的行业或产品,综合应用情景设计和FBS模型能帮助设计师确定产品开发方向,有效进行产品的概念设计。     

产品设计过程中非模型信息管理方法与管理系统

为了实现产品设计过程中各类非模型交互信息的有效记录与管理,提出了一种面向设计人员的非模型信息管理方法。为准确、客观和全面地记录设计信息,采用多样化信息载体工具对设计信息进行可视化描述,实现模型信息和非模型信息的集成管理与共享。将该方法无缝集成到产品设计软件平台和信息记录与管理软件中,开发出一套产品设计非模型信息管理系统,实现产品设计与信息管理的一体化。实例研究结果表明,设计人员通过该管理系统可实时查阅、描述和管理产品设计过程中产生的各类非模型信息,并能实现信息的自动分类与保存。研究表明所提出的管理方法和管理系统能够实现产品设计过程中非模型信息的有效管理,提高了其使用价值和产品的设计质量。     

CONDENSE: A concurrent design evaluation system for product design

In dealing with the issue of integrating design and manufacturing, concurrent design evaluation plays an important role. This paper presents a concurrent design evaluation system (CONDENSE) developed to help product designers in evaluating possible design solutions and design alternatives during the early stage of design. It consists of two important functions: a qualitative aspect evaluation applied during the stage of searching for combinations of solution principles to help determine the design specifications, and a quantitative aspect evaluation applied to provide information on performance, assemblability, manufacturability and costs to facilitate design selection. The framework of CONDENSE is based on a blackboard architecture that requires the classification of knowledge into appropriate knowledge sources. As design data are interrelated and may have uncertainty, a graph decomposition algorithm is used in constructing the knowledge sources, and a linguistic evaluation module is integrated with the qualitative aspect evaluation subsystem to deal with data uncertainty. The proposed system has been validated with respect to the design of golf club heads. The results, which have been validated by experienced designers, are promising and can contribute to the speed-up of design and development, improvement of design quality and facilitation of design selection.     

Iterative product design through group opinion evolution

More and more industrial products have begun to adopt iterative design modes. Opinions collected from all sides in each round of iterations are used as bases to make products that are able to capture the changes of customer demand dynamically and to respond to these changes in a timely manner. In this context, it becomes important for product designers and manufacturers to study the evolution of opinions as well as the product scheme along with design iteration to determine its regularity. This paper integrates the Hegselmann–Krause model into product improvement process, and develops a dynamic model from the view of opinion dynamics. The dynamic model simultaneously converges the evolution of customers’ opinions, professional designers’ opinions and the product scheme. The paper also analyses the interaction mechanism among different opinions as well as the mechanism between opinions and the product scheme. The experimental results determine that the product scheme, customers’ opinions and professional designers’ opinions can demonstrate differently but regular evolution patterns along with the design iteration according to the difference in confidence intervals or the difference caused by tending to adopt a more customer-driven design strategy or a more professional designer-driven design strategy. Finally, reasonable suggestions are provided to help manufacturers make product design strategies.     

An innovation funnel process for set-based conceptual design via DOE exploration,DEA selection and computer simulation

This paper presents a conceptual design approach including pattern creation from designers, alternative exploration with a DOE matrix, alternative analysis via computer simulation and alternative selection by DEA analysis. Designers possessing domain knowledge create various design patterns to meet the requirements of product performance and customer expectations. Then, based on these design patterns, the alternatives, considered as decision-making units (DMUs), are extracted from various quality level combinations by following the use of the DOE matrix. The nature of the DOE matrix ensures that distinctive representatives are constructed for all design alternatives. The total alternatives (DMUs) consist of the alternatives associated with all the patterns. Computer simulation with ANSYS software is introduced to convert the quality level combination of each alternative (DMU) into simulated outputs, which are further categorised into DEA inputs and DEA outputs for DEA frontier analysis. Four DEA methods, CCR-min input, CCR-max output, BCC-min input and BCC-max output, are used for analysing typical market representatives resulting from market uncertainty. The found efficiencies are used to rank and select the explored alternatives (DMUs) for the next stage of the detailed design. A bike-frame product is chosen as an example to demonstrate the proposed approach. The results clearly show that the proposed approach enables designers to economically select appropriate design alternatives that satisfy performance expectations during the conceptual design stage.     

用户认知视角下的产品设计方法研究

目的 为提高用户认知与产品映射关系的明确性与有效性,提升产品使用过程中用户认知的满意度。方法 从用户认知视角出发,结合信息加工模型,集成认知任务分析方法与结构方程模型,解构用户认知与产品体验的映射关系,构建用户认知视角下的产品设计方法流程。结果 以老年代步车作为设计研究对象。首先,通过认知任务分析方法明确产品“认知任务—认知路径—设计要素—产品体验”的设计分析流程;其次,引入结构方程模型以确定代步车设计要素权重,识别不同产品体验中的关键设计要素;最后,结合用户人群需求,进行设计决策和方案细化。结论 该方法可识别用户对产品的关键认知触点,减少用户认知在设计创造过程产生的“黑箱”,帮助设计师确定用户认知与产品体验之间的建构路径,为设计师在具体的实践活动中提供明确的设计依据,丰富了认知心理学在设计领域的实践研究。     

Simultaneous tolerancing for design and manufacturing

This paper presents a new tolerance design theory—simultaneous tolerancing— which works in the concurrent engineering context. After stating the need to develop a simultaneous tolerancing theory by showing the shortcomings of conventional tolerancing technique, the concept of simultaneous tolerancing is given, and its elements are briefly presented. Then we focus our attention on the development of a general mathematical model of optimal tolerancing supporting concurrent engineering. Two commonly used models, worst-case and statistical, are discussed in detail. Next, a method of ‘interim tolerances’, which help to determine an appropriate machining process without using functional tolerances, is proposed. The simultaneous tolerancing theory presented in this paper permits of determining directly optimal machining tolerances in product design, reducing the manufacturing cost and improving the quality of products. Finally, an example is given, showing that the proposed theory is feasible in practice.     

干洗机外观改型设计

以成飞洗涤设备有限责任公司的GFX-240型干洗机的外观改型设计为例,介绍了应用计算机辅助工业设计技术实现干洗机外观改型设计的设计流程及其关键技术与方法,阐述了产品内部结构设计与外形设计同步进行的并行设计思想,简要说明了在计算机虚拟环境中实现产品真实感表现的相关内容。依据产品形象设计原理及产品外观的语义感规律,完成了干洗机的形态设计和色彩设计,应用SolidWorks的建模功能与3dsmax的渲染功能实现了对干洗机的虚拟建模和真实效果渲染,从而成功地完成了干洗机的外观改型设计并取得良好的效果。     

面向创新设计的科学效应库研究

概念设计是确定功能原理解的过程,创新设计主要在这个阶段完成。行为是联系功能与结构的纽带,起着承上启下的重要作用,使用科学效应是实现功能到行为映射的有效手段。根据概念设计的过程模型, 提出了功能、行为与效应的关系模型和一个以功能为核心的功能-效应（FE）模型。建立了面向创新设计的科学效应库原型系统,系统具有效应搜索、效应显示、效应组合和生成报告等功能,为产品创新设计功能原理解提供有效支持。科学效应库是计算机辅助创新设计软件系统的一个功能模块。     

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.     

基于保质设计方法的产品开发决策研究

讨论了保质设计思想指导下的产品开发设计策略,并以产品开发设计的关键阶段——概念设计为对象,进一步研究了产品概念设计决策过程,建立了产品概念设计方案的评价指标体系和基于模糊优选理论的决策模型.     

并行产品设计人员学习与交流能力对下游活动影响的研究

设计人员的学习与交流能力是影响并行产品开发的重要因素.为了研究设计人员学习与交流能力对下游设计活动的影响,构建了学习知识量函数与返工率函数,提出了下游设计活动启动时刻与设计活动间信息交流次数的数学模型,研究了设计人员学习与交流能力对下游设计活动启动时刻及设计活动间信息交流次数的影响,得出了下游设计活动启动时刻与设计活动间信息交流次数的判断条件,并通过实例对判断条件进行了分析验证.根据判断条件以及设计人员学习与交流能力指数,计算出下游设计活动启动时刻与设计活动间信息交流次数.研究结果为缩短产品开发时间与减少产品开发成本提供了理论参考.     

基于感性意象的产品造型优化设计

针对当前消费者感性需求的提高,运用组合思想提出基于感性意象的产品造型优化设计方法.首先应用感性工学类目层次法得到产品的设计要素,再应用数量化一类理论建立感性意象和造型特征元素之间的对应关系,作为优化产品造型时的评判依据.然后应用蚁群算法对造型特征元素进行组合优化,实现了以少量的产品属性形态构建多样的产品造型方案,从而快速设计出满足消费者感性意象需求的产品.最后以电热水壶设计进行实例研究,结果表明运用该方法可有效地进行产品意象造型优化设计.     

基于可拓学的产品功能创新模型

产品功能是概念设计的出发点,创新是概念设计的灵魂.在分析现有产品功能模型功率键图的基础上,借鉴其思想,以物元形式描述功能,引入量值属性,建立创新设计的物元模型.从功能组合角度定义了功能之间的关系,以功能重组为出发点为设计者提供创新思路.