Methodology for capturing and formalizing DFM Knowledge

Design for manufacturing (DFM) practices lead to more competitive products from the point of view of cost, development time and quality. However, the success of considering manufacturing issues during design process would be higher if manufacturing information was more readily available and designers needed less experience to select information relevant to DFM.     

Domain independent shell for DfM and its application to sheet metal forming and injection molding

The objective for this research is to streamline design for manufacturing (DfM) analysis across all manufacturing domains and to provide transparency for DfM measures and evaluation process used. Generic steps are identified for performing manufacturability analysis and the design of a customizable manufacturability evaluation shell is presented. The shell covers several stages of manufacturability analysis (technical, economic) and can perform analyses at different levels of abstraction (qualitative, quantitative). The shell provides feedback to the designer at each level during the design process. By separating domain-specific knowledge from domain independent knowledge and creating an open architecture, the shell can be customized and expanded by the knowledge engineer and the user. The architecture of the shell is presented and its applications to manufacturability analysis for two domains, sheet metal and injection molding, are illustrated.     

SDMSim: A manufacturing service supply–demand matching simulator under cloud environment

Nowadays, with the introduction and application of new information technologies in manufacturing, various advanced manufacturing modes and national strategies have been put forward and paid more and more attention, such as Industry 4.0, Industrial Internet, Cyber-Physical System or Cyber Manufacturing, Made in China 2025, Internet Plus Manufacturing, Cloud Manufacturing, etc. For these modes and strategies, how to realize the effective and intelligent supply–demand matching (SDM) of various manufacturing resources and capabilities (MR&C) in the form of service is one of the common issues and aims. In order to provide a uniformed research platform for related researchers both in academic and industry, the concept of manufacturing service SDM simulator (SDMSim) is proposed in this paper. A hypernetwork based architecture for the simulator is designed, as well as its seven key functions and subsystems, including manufacturing service management, manufacturing task management, manufacturing service SDM hypernetwork, manufacturing service SDM problem formulation and configuration, matching and scheduling algorithms/strategies selection and design, statistical analysis, and visualization. It illustrates that SDMSim has the potential to serve the users of manufacturing service provider, manufacturing service consumer, manufacturing service operator in the field of SoM, as well as the related researchers.     

基于维度模型的知识管理系统

依据目前知识管理发展趋势,结合知识的特点,提出一种基于维度模型的知识管理系统解决方案。通过研究知识的一般特性,给出基于知识维度的知识模型,讨论基于维度模型的知识组织方式与管理方法,设计基于维度模型的知识管理系统,并引入基于维度模型的知识管理服务和搜索引擎等知识维度及相关信息的处理模块。实验结果表明,该系统可融合维度模型,具备个性化、交互性强、用户敏感性好等特点。     

Cost-effective design for injection molding

It is commonly agreed that a large proportion of the ultimate product cost is determined at product design stage. Therefore, a cost-effective design cannot be obtained unless all cost issues are resolved at early design stage. Therefore, instead of performing cost estimation after design, research presented in this paper aims to provide on-line cost evaluation and advisory to help product designers avoid cost-ineffective design. The objective can be obtained by (1) identifying factors that might affect product cost at each product design stage, (2) developing a design for cost effectiveness methodology that accommodates the concepts of concurrent engineering, and (3) developing a computer-based design for cost effectiveness system based on the proposed methodology. In this research, we focus on injection molding product design due to the advantages of injection molding process, such as high production rates, excellent quality and accuracy of the parts, and very long mold life. This paper first reviews and characterizes the conventional molding product development process with an emphasis on the identification of cost factors. Based on the results of process characterization, a cost model is developed, which depicts the relationships between cost factors and product development activities, as well as their relationships with product geometry. According to the product life cycle activities and the cost model, a design for cost effectiveness process is proposed. The process and the cost model are then employed for the development of a computer-based product design for cost effectiveness as one of the module of an integrated design for injection molding environment.     

以集合形式对知识再定义

知识在推动社会发展、服务社会生活过程中有着重要的作用,但人们对知识没有一个一致认可的定义。分析了已有的知识定义及分类,指出了其存在的不足,给出了集合形式的知识新定义--K-Set,并对K-Set定义进行了详细分析和解释。     

面向制造基于特征的零件定义模型的研究及其应用

零件信息的描述是建立适用ＣＥ／ＤＦＭ设计系统必须解决的问题,用于ＤＦＭ的 同于常规的ＣＡＤ／ＣＡＰＰ系统的零件模型。     

语义Web中工程设计类知识表示研究

研究了如何在语义Web中,实现工程设计类知识的表示与应用。对工程设计类各种异构知识进行统一描述,在此基础上,运用RDF(S)技术,建立了语义Web环境下,工程设计类知识的Ontology。提出了基于语义Web的知识存储模型以及面向上层应用程序的接口设计,为语义Web环境下工程设计类知识管理系统的开发提供了底层平台。     

DSM as a knowledge capture tool in CODE environment

A design structure matrix (DSM) provides a simple, compact, and visual representation of a complex system/ process. This paper shows how DSM, a system engineering tool, is applied as a knowledge capture (acquisition) tool in a generic NPD process. The acquired knowledge (identified in the DSM) is provided in the form of Questionnaires, which are organized into five performance indicators of the organization namely ‘Marketing’, ‘Technical’, ‘Financial’, ‘Resource Management’, and ‘Project Management’. Industrial application is carried out for knowledge validation. It is found form the application that the acquired knowledge helps NPD teams, managers and stakeholders to benchmark their NPD endeavor and select areas to focus their improvement efforts (up to 80% valid).     

Design for agility: a scheduling perspective

Agility is the ability of a company to produce a variety of products in a short time and at a low cost. This demands that products and manufacturing systems be simple, robust, and flexible to allow for quick response to the changing market. Scheduling of manufacturing systems in a changing environment is complex. This paper attempts to simplify scheduling of manufacturing systems through appropriate design of products and manufacturing systems. An attempt has been made to generate rules that allow to design products and systems for easy scheduling. Four design for agility rules are proposed in the paper. The first rule deals with decomposition of a manufacturing system. The rule simplifies the scheduling problem and reduces the total changeover cost. The second rule is concerned with design of products with robust scheduling characteristics. Product designs with robust scheduling characteristics can improve the response of a manufacturing system to the changes in the product demand and mix and reconfigurability of the system. The third rule results in a streamlined assembly line which has the type of product flow that simplifies scheduling. The fourth rule emphasizes the reduction of the number of stations in an assembly line. Examples are provided to demonstrate the benefits from using these rules. The implementation of the four rules is also discussed.     

A glance of technology efforts for design-for-manufacturing in nano-scale CMOS processes

This paper overviews design for manufacturing （DFM） for IC design in nano-CMOS technologies. Process/device issues relevant to the manufacturability of ICs in advanced CMOS technologies will be presented first before an exploration on process/device modeling for DFM is done. The discussion also covers a brief introduction of DFM-aware of design flow and EDA efforts to better handle the design-manufacturing interface in very large scale IC design environment.     

Simulated annealing with auxiliary knowledge for process planning optimization in reconfigurable manufacturing

In this paper, three simulated annealing based algorithms that exploit auxiliary knowledge in different ways are devised and employed to handle a manufacturing process planning problem for reconfigurable manufacturing. These algorithms are configured based on a generic combination of the simulated annealing technique with; (a) heuristic knowledge, and (b) metaknowledge. Capabilities of the implemented algorithms are tested and their performances compared against a basic simulated annealing algorithm. Computational and optimization performances of the implemented algorithms are investigated and analyzed for two problem sizes. Each problem size consists of five different forms of a manufacturing process planning problem. The five forms are differentiated by five alternative objective functions. Experimental results show that the implemented simulated annealing algorithms are able to converge to good solutions in reasonable time. A computational analysis indicates that significant improvements towards a better optimal solution can be gained by implementing simulated annealing based algorithms that are supported by auxiliary knowledge.     

基于涟波下降规则的设计知识管理系统

设计过程是一个知识密集型过程.为了向企业提供有效和准确的设计知识,在分析涟波下降规则工作原理的基础上,提出了基于涟波下降规则的设计知识管理系统架构,给出了该系统的定义,进一步研究了该系统的主要功能.依据提出的架构及其主要功能,通过一个应用实例,验证了研究成果的有效性.     

A Social Media framework to support Engineering Design Communication

Engineering Design Communication (EDC) is fundamental to almost all Engineering Design activities as it provides the ability for knowledge and information to be shared between engineers. It is part of ‘what we do’. This communication contains a great deal of rationale relating to the evolution of Product Development and is essential for understanding ‘why the product is the way it is’. The need to support EDC is becoming more important due to the fact that Product Development is becoming more distributed, multi-disciplinary and involving greater re-use of past designs. With the advent of Social Media (SM), it is argued that there is the technical capability to provide more effective support for EDC within a computer-mediated environment. In order to explore this potential, this paper defines the requirements for the effective support of EDC through an extensive review of the literature. It then discusses the suitability of a SM approach and then presents the theoretical foundations of a SM framework to support EDC.     

An intelligent system for automatic layout routing in aerospace design

This paper discusses the development of an intelligent routing system for automating design of electrical wiring harnesses and pipes in aircraft. The system employs knowledge based engineering (KBE) methods and technologies for capturing and implementing rules and engineering knowledge relating to the routing process. The system reads a mesh of three dimensional structure and obstacles falling within a given search space and connects source and target terminals satisfying a knowledge base of design rules and best practices. Routed paths are output as computer aided design (CAD) readable geometry, and a finite element (FE) mesh consisting of geometry, routed paths and a knowledge layer providing detail of the rules and knowledge implemented in the process. Use of this intelligent routing system provides structure to the routing design process and has potential to deliver significant savings in time and cost.