以更快的速度获取更好的产品：怎样实现整体开发方案？

对产品开发和制造作整体考虑,提出了在创造价值链中进行思考的要求。除了产品开发之外,三维ＣＡＤ建模方式的普遍使用使得生产准备和制造的水平有了较大提高。在已改进的快速原型成型技术、材料和后续过程的基础上,产品开发有加强转向快速制造的趋势。     

Incorporation of high recyclability material selection in computer aided design

Manufacturing are now under increasing pressure of tighten environmental legislation to preserve natural resources. Product design, as a part of manufacturing activities, has to be more concern to deliver product specification with reduced environmental impact. Design for Recycling (DFR) is one of the promising approaches in prolonging material utilization of a product in the early stage of design. DFR focus on harmonizing product design with the recycling practices in order to minimize the loss of valuable materials and preventing unnecessary waste streams at the end of product’s life. In turn, it limits the usage of natural resources.To implement DFR, designers are faced with the challenge of compromising different design objectives such as cost, functional or technical requirements and product’s recyclability performance. This paper attempts to propose an intelligent approach that could facilitate designers to make an easy and quick recyclability assessment as well as selecting recyclable materials integrated with computer aided design. In this paper, the use of fuzzy inference system and genetic algorithm is proposed to optimize the multi-objective problem in the selection of recyclable materials. Case study on the actual conceptual design using computer aided design environment is demonstrated and showing that the proposed method successfully can be applied concurrently during product design. Comparison of proposed method with Sustainability Express Solid Work is also presented. The proposed method can assist product designers to design a high recyclability product without ignoring technical perspectives.     

网络环境下快速原型信息岛的构建

简要介绍了基于信息岛的设计管理模式,并提出了快速原型信息岛的概念,同时阐述了构建基于网络环境的快速原型信息岛的必要性.作者主要建立了网络环境下快速原型信息岛的结构框架,分析了其Browser/Server的信息管理模式、主要功能模块、运作流程及开发环境.最后还阐述了该信息岛的应用前景及理论意义.     

适于快速成型制造工艺的短纤维增强复合材料研究

对短切玻璃纤维增强ABS 复合材料进行了一系列的改性研究。短切玻纤的加入, 能提高纯ABS 的强度、硬度且显著降低ABS 的收缩率, 减小制品的形变, 但同时使材料变脆。本实验通过适量加入增韧剂和增容剂, 较大提高了挤出的复合材料丝的韧性及力学性能, 从而使制备出的短切玻璃纤维增强复合材料适用于熔融沉积制造(FDM ) 工艺。并用改性了的短切玻璃纤维增强ABS 作为原料, 在快速成型机上制备试样, 测定其力学性能, 从宏观及微观上对改性效果进行了分析与评定。     

The Design Guidelines (DGLs), a knowledge-based system for industrial design developed accordingly to ISO-GPS (Geometrical Product Specifications) concepts

Product design and optimisation today involves so many fields of expertise, many of which are in rapid evolution, that it can be very difficult for the designer to manage them. This paper describes the development of the DGLs (Design Guidelines), a knowledge-based tool that could be of great help to designers and engineers in modifying their products to get compatibility with different manufacturing and verification technologies. The current release of the DGLs, heavily influenced by the adoption of some ISO-GPS (Geometrical Product Specification) concepts, has been validated using the Rapid Prototyping technique called FDM (Fluid Deposition Modelling) and the CMM (Coordinate Measuring Machine) verification technique.     

Laser sintering of polyamides and other polymers

With the evolution of additive techniques from prototyping tools (Rapid Prototyping; RP) to the production of actual end-use parts (Additive Manufacturing; AM), there is a growing need to develop and be able to process a much greater variety of materials than is currently possible. The handful of current polymeric materials that exist for processing by additive techniques does not meet the requirements of the majority of commercial products. There is therefore considerable interest from industrial and academic organisations, who realise the capabilities this technology has in the design and implementation of products, to increase material choice and to have a comprehensive understanding of the fundamental material properties. This review paper looks at the factors that need to be considered when selecting and processing polymers and the research that has been carried out to date, focussing on laser sintering, which is one of the most established and widely used Additive Manufacturing approaches. It also examines the limitations of current laser sintering systems in relation to the processing of polymer materials. The effect this has on the development of new and improved materials for laser sintering is evaluated, in addition to the difficulties experienced in maintaining consistency with current laser sintering polymers.     

快速成形技术中材料成形性的研究进展

简要介绍了几种典型的快速成形技术的基本原理 ,分析了快速成形技术中材料的研究和应用现状 ,讨论了快速成形技术中材料的快速成形性问题 ,并指出研究和开发快速成形材料和对新材料的快速成形性的研究是材料与制造工程科学的一个重要发展方向     

Identified research directions for using manufacturing knowledge earlier in the product life cycle

Design for manufacturing (DFM), especially the use of manufacturing knowledge to support design decisions, has received attention in the academic domain. However, industry practice has not been studied enough to provide solutions that are mature for industry. The current state of the art for DFM is often rule-based functionality within computer-aided design (CAD) systems that enforce specific design requirements. That rule-based functionality may or may not dynamically affect geometry definition. And, if rule-based functionality exists in the CAD system, it is typically a customisation on a case-by-case basis. Manufacturing knowledge is a phrase with vast meanings, which may include knowledge on the effects of material properties decisions, machine and process capabilities or understanding the unintended consequences of design decisions on manufacturing. One of the DFM questions to answer is: How can manufacturing knowledge, depending on its definition, be used earlier in the product life cycle to enable a more collaborative development environment? This paper will discuss the results of a workshop on manufacturing knowledge that highlights several research questions needing more study. This paper proposes recommendations for investigating the relationship of manufacturing knowledge with shape, behaviour and context characteristics of a product to produce a better understanding of what knowledge is most important. In addition, the proposal includes recommendations for investigating the system-level barriers to reusing manufacturing knowledge and how model-based manufacturing may ease the burden of knowledge sharing. Lastly, the proposal addresses the direction of future research for holistic solutions of using manufacturing knowledge earlier in the product life cycle.     

The integration of manufacturing and cost information into the engineering design process

In manufacturing systems engaged in the batch manufacture of discrete products, critical decisions on materials and processes are made during the design phase, decisions having significant impact on costs of production. A new computer aided design tool has been developed to enable product designers in small to medium size companies to incorporate manufacturability and cost criteria into their decision making. The paper describes the rationale of the system and its mode of operation. Experiments to validate its practicality and usefulness have yielded encouraging results.     

A CAD/CAM system for process planning and optimization in LOM (Laminated Object Manufacturing)

Rapid Prototyping (RP) technologies have emerged as a powerful set of manufacturing technologies in recent years. While these technologies invariably provide tremendous time savings over traditional methods for the manufacture of design prototypes, most are still quite inefficient. This paper proposes two ideas: (i), that these processes can be significantly optimized by using better process planning; and (ii), that several of these technologies use similar core planning technologies for optimization. The first hypothesis is verified in this paper by presenting an improved process planning system for one RP technology, Laminated Object Manufacturing (LOM). The second observation led us to develop an open architecture planning system for a host of RP technologies. A testbed software system using these ideas has been developed and is presented in this paper. While the methodologies developed can work with the current industry standard STL format for storing object CAD data, the software is planned purely to work using exact solid models and direct slicing methods.     

The designer as ‘gatekeeper’ in manufacturing industry

For the past three years the Design Innovation Group at the Open University in collaboration with Vivien Walsh at UMIST has been examining the processes, practices and management of product design, development and innovation in several sectors of manufacturing industry.This paper presents some of the findings, in particular from the survey of the plastics products sector, but with additional evidence from a preliminary analysis of data in the office furniture, domestic heating equipment and electronic business equipment industries.The focus of the paper is on the employment and activities of product designers and their role as ‘gatekeepers’, who, in the commercially successful, ‘design-conscious’ firms, manage to integrate the contributions of marketing, design and production in new product development.The paper also includes some evidence on the relationship between ‘good design’ and business performance.     

设计是人类未来不被毁灭的“第三种智慧”

设计从一开始就是为了解决“小生产方式”不适应“大生产方式”而被催生出来的一种生产关系,它将被证实为人类未来不被毁灭的,除科学和艺术之外的第三种智慧和能力。在经济全球化、技术潜能扩延、需求地域化、消费个性化的当今,设计本来应有的职责被严重地歪曲了,人类未来生存方式的变革正在酝酿。设计拉动型制造业将成为我国制造业发展的方向,从而促进我国从制造大国变为制造强国和设计强国。     

Using business critical design rules to frame new architecture introduction in multi-architecture portfolios

When introducing new architectures to an industrial portfolio, counting multiple existing product and manufacturing solutions, time-to-market and investments in manufacturing equipment can be significantly reduced if new concepts are aligned with the existing portfolio. This can be done through component sharing, or sharing critical design principles. This alignment is not trivial, as extensive design knowledge is needed to overview a portfolio with many, often highly different products and manufacturing lines. In this paper, we suggest establishing a frame of reference for new-product introduction based on several ‘game rules’, or Business Critical Design Rules (BCDRs), which denote the most critical features of the product and manufacturing architectures, and should be considered an obligatory reference for design when introducing new architectures. BCDRs are derived from the portfolio, architecture and module levels, including modelling of the most critical links between the product and manufacturing domains. The suggested modelling principle has been tested as a frame for new-architecture introduction, capturing critical modularisation principles in a large and global OEM. Application of the suggested method revealed a potential for reducing time-to-market and potentially cutting 35% off investments in new manufacturing equipment when introducing new products in the portfolio.     

A hybrid case-based reasoning CAD system for injection mould design

Injection mould design generally lies on the critical path of a new product development. The design efficiency will have significant impact on the overall lead time of a new product. This paper presents a prototype injection mould-design system using a hybrid case-based reasoning (HCBR) approach. Case-based reasoning (CBR) is a solving paradigm that uses previous episodes on solving problems similar to the problem at hand (the new problem) as the basis for solving the new problem. In this hybrid system, CBR is incorporated with generalized design knowledge, and provides a flexible and comprehensive model of design. The knowledge base of the system would be accessed by mould designers through interactive programs so that their own intelligence and experience could also be incorporated with the total mould design. The approach provides a workable model of mould design system with CBR and knowledge-based expert system intelligent support, which could suggest good and proven design solutions to new design problems quickly, avoiding the time necessary to create those designs from scratch, for the plastic products manufacturing industry.     

Optimal design for additive manufacturing of heterogeneous objects using ultrasonic consolidation

Rapid prototyping (RP) technologies, such as Laser Engineering Net Shaping (LENS®) and Ultrasonic Consolidation (UC), can be used to fabricate heterogeneous objects composed of more than one material, wherein spatially varied microscopic structural details produce continuously or discretely changing mechanical or thermal properties on a macroscopic scale. These objects are engineered to achieve a potentially enhanced functional performance. Past research on the design of such objects has focused on representation, modeling, and desired functional performance. However, the inherent constraints in RP processes, such as system capability, size and shape of raw materials, and processing time, lead to fabricated objects that may not meet the designer's original intent. To overcome this situation, the research presented in this paper focuses on developing an approach— Design for Additive Manufacturing (DfAM)—to implement identified manufacturing constraints into the design process. Previous work has applied DfAM to the design of heterogeneous objects fabricated using the LENS® process. Two manufacturing constraints for this process, namely the achievable volume fractions and the processing time, were identified and incorporated into the DfAM. In this paper, the DfAM approach is extended to the design and manufacture of heterogeneous objects for the UC process. Constraints on the possible volume fraction values and on the gradient material direction are two identified manufacturing limitations, which are incorporated into the design process. An element-based finite element (FE) representation is extended to model layered heterogeneous objects. Each element is composed of metal foils of different materials according to specific design parameters. An evolutionary-based optimizer is used for its ability to handle the type of multi-modal problems encountered in the design of heterogeneous objects. The multi-criteria design problem, consisting of finding the optimal material composition along the build direction, that satisfies the functions of minimum weight and structural deformation, is implemented and solved. A three-dimensional I-beam made of two materials—aluminum for lightweight and steel for better strength characteristics—is used to illustrate the DfAM approach and its implementation for the design of heterogeneous objects using the UC process.     

Value creation through design for scalability of reconfigurable manufacturing systems

Rapid and cost-effective scalability of the throughput of manufacturing systems is an invaluable feature for the management of manufacturing enterprises. System design for scalability allows the enterprise to build a manufacturing system to supply the current demand, and upgrade its throughput in the future, in a cost-effective manner, to meet possible higher market demand in a timely manner. To possess this capability, the manufacturing system must be designed at the outset for future expansions in its throughput to enable growths in supply exactly when needed by the market. A mathematical method that maximises the system throughput after reconfiguration is proposed, and an industrial case is presented to validate the method. The paper offers a set of principles for system design for scalability to guide designers of modern manufacturing systems.     

Integrated product development

Manufacturing and design are very closely related. The manufacturing capabilities available impact the scope of design, while design for manufacturing ensures the economic success of the products. Furthermore, the major goals of firms in the nineties are to significantly reduce product costs and time to market (TTM). To meet these goals, quality product designs that meet customers’ needs have to be developed. Design methods such as Quality Function Deployment and Pugh’s concept selection technique have been used to significantly improve engineering design processes. Developed as separate tools, however, they are difficult to integrate and coordinate in the total design process, since the relationship of the two methods is often unclear. This paper demonstrates, through a case study, that these methods are in fact results of a similar underlying concept. Design problems and solutions are unified by the concept of engineering models. An engineering model is a set of equations that relates the design variables to the performance metrics used to quantify performance of a product. Together with the engineering models, Quality Function Deployment and Pugh’s concept selection technique have been used in the design and development of a hematology machine from concept to prototype.     

Development of an AI-based Rapid Manufacturing Advice System

The purpose of this paper is to assess the possibility of using Rapid Manufacturing (RM) as a final manufacturing route through a comparison of RM capabilities vs. conventional manufacturing routes. This is done by means of a computer-aided system intended to guide the designer in the selection of optimum production parameters according to general product requirements proper of the first design stages. The proposed system makes use of a number of artificial intelligence (AI) tools, namely: fuzzy inference, relational databases and rule-based decision making to reach an optimum solution. A pilot application developed in Matlab® is presented to illustrate the system application on a real mechanical part used as a case study. In the article it is shown how the proposed model may be useful for presenting feasible RM alternatives for parts and products not originally intended for additive manufacture. It also indicates when no RM alternatives are suitable for the given tasks, thus indicating those areas of knowledge which are necessary to expand in order to have at disposal comprehensive and reliable info on RM to compete with conventional processes.     

Materials analysis of stereolithography resins for use in Rapid Manufacturing

The use of Rapid Prototyping (RP) techniques for the production of end-use parts is increasing to a stage where Rapid Manufacturing is being undertaken. This paper documents significant initial investigations into the properties of Accura SI40 and SL7560 resins which represent two state of the art stereolithography resins that are aimed at end-use part manufacture. This information has previously been unavailable and is vital for their consideration in end-use part manufacture. The impact of various levels of post curing (ultraviolet and thermal) on the tensile, flexural and impact properties are investigated and correlated with differential scanning calorimetry (DSC) analysis. The isotropy/anisotropy nature of the two materials and also the effect of the notch creation method on the impact resistance were also studied.