Object-oriented modelling of manufacturing information system for collaborative design

Object-oriented technology has been widely acclaimed as offering a revolution in computing that is resolving a myriad of problems inherent in developing and managing organisational information processing capabilities. Although its foundations arose in computer programming languages, object-oriented technology has implications for a wide range of business computing activities including: programming, analysis and design, information management, and information sharing. The problematic issues in the development of manufacturing software systems are related to the various characteristics of manufacturing systems, which are wide, dynamic and complex. Design for manufacturing (DFM) is the integrated practice of designing components while considering their manufacturability, and its benefits are widely acknowledged in the industry. A model has been developed using object oriented technology, after analysing the fundamental elements necessary for modelling manufacturing and process planning framework used in collaborative design and manufacturing in machine tool manufacturing. The main components of this model are: process planning model (PPM), manufacturing activity model (MAM), manufacturing resource model (MRM) and manufacturing cost and time model. We are using ontologies in conjunction with specific conceptual models, which can contribute to improve the interoperability between these models. The performance of this model is shown by means of one real world case. The developed manufacturing information based design tool integrated with an intelligence design system can be used for collaborative design and manufacturing, which will support machine tool designers’ to achieve cost effective and timely design.     

CAQFD概念设计专家系统模式的研究

质量功能配置(QFD）对满足用户需求的产品概念设计提供了一种切实可行的方法。探讨了计算机辅助QFD概念设计专家系统的设计模型和计算机实现的关键技术。对用户需求信息的获取方法进行了研究,构建了用户需求知识表达的拓扑结构。从知识工程的角度,提出了基于数据库的知识表达模式和推理方式,设计了专家系统的知识推理过程。最后以高速专用磨床的主轴前支承轴承的概念设计为例,进行了系统的应用验证,取得了满意的效果。     

Normalisation models for prioritising design requirements for quality function deployment processes

The prioritisation of design requirements is critical for determining resource allocation in the new product design stage through the quality function deployment (QFD) planning processes. To prioritise design requirements, normalisation models are usually used to perform aggregation and normalisation functions. Recognising the weakness of the Wasserman normalisation model from both theoretical and practical viewpoints, this paper proposes an improved normalisation model for the aggregation and normalisation functions. It is verified that the proposed model satisfies Lyman’s normalisation requirement and avoids the problem of Wasserman’s normalisation model. In addition, a normalisation model that takes into account the correlation among customer requirements is also developed to complete a generalised normalisation model for QFD planning processes. A product design case is presented to demonstrate the advantages of the proposed normalisation models.     

Classes of design — classes of methods — classes of tools

It is unrealistic to expect one computer-aided design tool to sufficiently support any one given design process. Yet it is necessary to define new CAD programs that give semantic support in design. To this end, the paper first differentiates classes of design and then attempts to establish relations between the defined classes and appropriate methods and computer-aided design tools. In three main sections it describes routine, innovative and creative design; top-down, bottom-up and case-based methods; and a set of corresponding design tools. The purpose of the paper is to make a contribution to the definition of domain specific aspects of CAD and to propose a mapping between processes, methods, and tools.     

An industrial workstation characterization and selection using quality function deployment

In flexible manufacturing, the need to evaluate various process design concepts that can survive and deliver better performance through many families and generations of products becomes more urgent. It is important to derive characteristics of the assembly station that are measurable and controllable. These characteristics should satisfy process and products needs. In this paper, we report on the findings of a cross-functional team, representing Product Development and Manufacturing Engineering, that was assigned the design of the advanced assembly station required to load magnetic heads suspended by actuator arms in between a stack of media disks in the assembly of direct access storage devices (DASD) also known as hard disk drives (HDD). The core of our work was based on a Quality Function Deployment (QFD) approach that included the construction of a house of quality (John Hauser and Don Clausing, ‘The house of quality’ Technical Report, Operations Department, Harvard Business School, Boston, MA 02163; Bob King, ‘Better Designs in Half the Time, Implementing Quality Function Deployment in America, 3rd edn, Goal/QPC Publishing, MA, 1989) which treated this process step as a system. We present results of the team efforts and describe the progressive stages that took place from the gathering of the station customers’ wants and needs to the selection of a station design. © 1997 John Wiley & Sons Ltd.     

Optimal new product design using quality function deployment with empirical value functions

The house of quality (HOQ) has been widely proposed as a method for capturing the voice of the customer (VOC) when developing requirements for new products. The methodology has lacked a formal mechanism for trading off customer preferences with technical feasibility and economic reality. We propose a non‐linear mathematical program for determining the optimal engineering specifications during new product development as a function of elicited customer value functions, engineering development and production costs and development time constraints. The model is shown to be computationally feasible for realistic‐size problems and to outperform heuristic approaches. Copyright © 1999 John Wiley & Sons, Ltd.     

A novel fuzzy linguistic model for prioritising engineering design requirements in quality function deployment under uncertainties

Quality function deployment (QFD) is a planning and problem-solving tool gaining wide acceptance for translating customer requirements (CRs) into the design requirements (DRs) of a product. Deriving the priority order of DRs from input variables is a crucial step in applying QFD. Due to the inherent vagueness or impreciseness in QFD, the use of fuzzy linguistic variables for prioritising DRs has become more and more important in QFD applications. Existing approaches make use of the associated fuzzy membership functions of linguistic labels based on the fuzzy extension principle. However, an inherent limitation of such fuzzy linguistic approaches is the information loss caused by approximation processes, which eventually implies a lack of precision in the final results. This paper proposes an alternative approach to prioritising engineering DRs in QFD based on the order-based semantics of linguistic information and fuzzy preference relations of linguistic profiles, under random interpretations of customers, design team and CRs. Ultimately, this approach enhances the fuzzy-computation-based models proposed in the previous studies by overcoming the mentioned limitations. A case study taken from the literature is used to illuminate the proposed technique and to compare with the previous techniques based on fuzzy computation.     

Economic parameter design for ultra-fast laser micro-drilling process

The basic requirement in this type of micro-drilling process is to achieve high product quality with the minimum machining cost, which can be realised through parameter design. In this paper, we propose a new economic parameter design under the framework of Bayesian modelling and optimisation. First of all, the Bayesian seemingly unrelated regression (SUR) models are utilised to develop the relationship models between input factors and output responses in the laser micro-drilling process. After that, simulated response values which reflect the real laser micro-drilling process are obtained by using the Gibbs sampling procedure. Moreover, a novel rejection cost function and a quality loss function are constructed based on the simulated responses. Finally, an optimisation scheme integrating the rejection cost (i.e. rework cost and scrap cost) function and the quality loss function is implemented by using multi-objective genetic algorithm to find feasible economic parameter settings for laser micro-drilling process.     

三维实体设计与并行工程

三维实体设计技术为企业实现基于并行工程的产品设计和改型提供了强有力的技术支持。笔者介绍了并行工程的概念,以及基于并行工程的产品设计方法的特点,分析了传统产品设计与并行设计流程的差别。在此基础上,指出了三维实体设计对实现并行、一体化设计和集成化协同工作的支持,并用实例说明了这种方法在汽车覆盖件模具设计开发中的应用。     

产品全寿命周期工程设计的实现技术

由于人类可持续发展的需要，现代制造系统必须是有利于资源节省和环境保护的绿色制造系统。在分析产品全寿命周期工程设计（LCED）功能目标的基础上，构造了产品全寿命周期工程设计的基本体系，引用质量功能配置（QFD）方法，探讨了其实现技术，从而有效地产品研究与开发中的环境资源约束，市场需求约束及企业开发能力约束之间的冲突。     

Methods and tools for decision making in engineering design

This paper describes the background to the setting up of the Cambridge Engineering Design Centre. An overview of the design research and applications programme of the Cambridge EDC is given. Four research themes are identified: functional modelling, configuration and manufacturing optimization, materials and process selection, and process interpretation and management. Application areas include aerospace systems, heavy duty vehicles and medical equipment.     

机械产品中面向绿色成本的设计

以机械产品材料利用率为基础,构造了绿色度系数,乘以原来成本,转化成为绿色成本,并代替原来成本作为对设计优劣评判标准,将绿色设计思想引入面向成本的设计中,将面向成本的设计转变为面向绿色成本的设计.     

RADS — a computer package for refrigeration analysis, design and simulation

A commercially available computer package for refrigeration analysis, design and simulation is described. Its main applications are heat load determination, multi-stage compression plant layout design, and simulation of the interactions between refrigerant plant, applications and control systems.     

建筑工程并行设计研究

介绍了并行工程的定义和特点；针对并行工程对建筑产品开发过程的要求，构建了建筑工程并行设计实施的集成框架，包括并行设计集成的内容、集成的功能及以三域划分的总体结构；论述了建筑工程并行设计实施的特点；构建了基于共享数据库的各专业设计层次的关系。     

基于维修的DFA/D系统设计

 DFX 是实现产品并行设计的重要工具，考虑到产品维修活动中的拆卸与装配问题，指出研究面向维修的DFA／D)的必要性．在借鉴传统DFA，DFD研究的基础上，阐明面向维修的DFA／D的结构设计及其关键技术，初步证明了面向维修的DFA／D作为设计工具实现维修性并行设计具有现实可行性．     

Back to the future with CAD: its impact on product design and development

This paper briefly examines the history of the management and organisation of the product development cycle. It looks at some of the key factors that have affected product development, and how information technology through CAD may have opened the door to a simultaneous product design process that has more in common with ‘older’ craft-based methods than those developed in the recent industrial era.     

三次设计的扩展介绍与探讨

三次设计是一种保证产品质量、降低成本的有效设计方法，在工业发达国家受到极大重视。本文对经典三次设计的基本思想和方法作了详细阐述，归纳总结出现代三次设计的一般模式，并就三次设计与并行工程的关系作了有益的探讨。     

Refrigeration and the environment — issues and strategies for the future

Worldwide reactions to the debates on global warming and ozone depletion have led to social responses and legislative measures which have serious implications for refrigeration and associated industries. This paper discusses the problems to be faced, and the ways in which the industry can contribute to meeting the wider global objectives. The discussion considers the choice and availability of working fluids, the increased complexity of using fluid mixtures, and the risk of losing the simplicity in design and construction which was possible with CFC single fluids. Education and training are presented as issues because of the changes in technology.