Information requirements analysis for holonic manufacturing systems in a virtual environment

The design and development of holonic manufacturing systems requires careful, and sometimes risky, decision making to ensure that they will successfully satisfy the demands of an ever-changing market. In this paper, the authors propose a methodology for a holonic manufacturing systems requirement analysis that is based on a virtual reality approach and aimed at assisting designers of such systems along the entire systems design and development process. Exploiting virtual reality helps the user collect valid information quickly and in a correct form by putting the user and the information support elements in direct relation with the operation of the system in a more realistic environment. A prototype software system tool is designed to realise the features outlined in each phase of the methodology. A virtual manufacturing environment for matching the physical and the information model domains is utilised to delineate the information system requirements of holonic manufacturing systems implementation. A set of rules and a knowledge base is appended to the virtual environment to remove any inconsistency that could arise between the material and the information flows during the requirement analysis.     

Developing a manufacturing technology for the components made of a multiphase perfect material

A component made up of a perfect combination of different materials (most often including homogeneous materials and three different types of heterogeneous materials, i.e., composite materials, functionally graded materials, and heterogeneous materials with a periodic microstructure) in its different portions for a specific application is considered to be a component made of a multiphase perfect material. To design and represent such components, a corresponding computer-aided design method and a CAD modeling method have been developed. Although, there is no existing manufacturing method and facility for such components. Their fabrication entails four steps described in this paper: analysis of the requirements of their manufacture; review of the currently available layered manufacturing, micro-fabrications, and hybrid manufacturing technologies; presentation of a new hybrid layered manufacturing technology (including its manufacturing process and the principle scheme of its corresponding manufacturing facilities); and implementation of the manufacturing simulation by means of virtual manufacturing technology.     

A CAD-based visual simulator for designing flexible automated material handling and transportation systems

A software system is presented for simulating the behaviour of an automated material handling and transportation system typically used in flexible manufacturing. The program is written in the UPL language on top of a commercially available CAD system. It makes use of a discrete event simulation model written in ECSL to generate a schedule of events defining an animation scenario. The program relies on a graphical library of modular component elements that enable structured automated material handling and transportation system elements to be created. The motion patterns are generic and are implemented as procedures that can be associated with any entity as required. Motion employs the concept of entity associativity within the CAD environment in order to apply the same motion patterns to groups of entities. The latter retain, however, their individual motion specification. Advantages of the program include inherent integration with CAM, availability of a host of parent CAD facilities and thus ability to visualise facility performance and to appraise design in detail.     

WEB-BASED VIRTUAL CNC MACHINE MODELING AND OPERATION

A CNC simulation system based on internet for operation training of manufacturing facility and manufacturing process simulation is proposed. Firstly, the system framework and a rapid modeling method of CNC machine tool are studied under the virtual environment based on PolyTrans and CAD software. Then, a new method is proposed to enhance and expand the interactive ability of virtual reality modeling language(VRML) by attaining communication among VRML, JavaApplet, JavaScript and Html so as to realize the virtual operation for CNC machine tool. Moreover, the algorithm of material removed simulation based on VRML Z-map is presented. The advantages of this algorithm include less memory requirement and much higher computation. Lastly, the CNC milling machine is taken as an illustrative example for the prototype development in order to validate the feasibility of the proposed approach.     

Material bead deposition with 2 + 2 ½ multi-axis machining process planning strategies with virtual verification for extruded geometry

Process planning for hybrid manufacturing, where additive operations can be interlaced with machining operations, is in its infancy. New plastic- and metal-based hybrid manufacturing systems are being developed that integrate both additive manufacturing (AM) and subtractive (machining) operations. This introduces new process planning challenges. The focus of this research is to explore process planning solution approaches when using a hybrid manufacturing approach. Concepts such as localized AM build ups, adding stock to a CAD model or section for subsequent removal, and machining an AM stock model are investigated and illustrated using virtual simulations. A case study using a hybrid laser cladding process is used to demonstrate the opportunities associated with a hybrid solution. However, unlike machining, the process characteristics from system to system vary greatly. These are portrayed via a high power, high material deposition feed rate laser cladding system. There are unique challenges associated with AM processes and hybrid manufacturing. New tools and design rules need to be developed for this manufacturing solution to reach its potential.     

A STEP AP224 agent-based early manufacturability assessment environment using XML

Early design assessment activities have a significant impact on reducing the cost of manufacture. The efficient utilisation of the product development time and the level of coordination of the early design activities between the major stakeholders are becoming key factors for success in manufacturing today. The paper reports on a new distributed early design manufacturability assessment methodology using collaborative autonomous agents. A product data model compliant with STEP AP224 and corresponding process and facility data models are proposed to support the decision-making process. XML was used as a medium for exchange of requests and information between design, manufacturing, and facility planning agents. A prototype Web-enabled system for rapid product manufacturability assessment in the extended enterprise has been developed using distributed multi-agent CORBA objects. The reported research is a step towards the development of a generic prototype tool for collaborative design evaluation and rapid assessment of the manufacturing feasibility and resource availability at different stages of the product development process.     

分布式虚拟环境下的产品协同设计与制造

虚拟技术和计算机支持的协同工作（CSCW）技术已经渗透在设计与制造的活动中,并推动制造信息集成和网络协同设计与制造技术的发展。文中分析和讨论了分布式虚拟环境中的协同设计与制造系统的特点及其本要求,以五层结构形式给出了一处系统实现的框架模型。     

Autonomous Behaviour in Automated Manufacturing Systems

In this paper, a decision-theoretic approach is provided to model the autonomous behaviour among intelligent agents, e.g. machines, in automated manufacturing systems (AMS). The automated manufacturing systems make available agile manu-facturing systems with the characteristic of quick response to the customers’ needs. An autonomous agent can use the decision method to model multi-agent situations and behave rationally based on this decision-theoretic approach. The AMS is constructed in a matrix framework for rule-based controller design. The controller is comprised of inner and outer loops, where the inner loops are decision-free with no shared-resource problems. The outer loops involve shared-resources, parts dispatching, and route selection, and so require a conflict resolution command input, uc. The decision-making input uc is selected based on an agent-oriented paradigm. This paradigm views the production process in an automated manufacturing facility as distributed among autonomous manufacturing agents. The payoff matrix representation and operations research techniques are used to facilitate the agents’ decision making. This paper shows how the matrices depicting the decision-making situations of manufacturing agents can be arrived at. An example with a reentrant flow system characteristic for semiconductor manufacturing plants is provided.     

Development of a generative CAPP system for axisymmetric components for a job shop environment

Process planning is a function in a manufacturing organization that selects the manufacturing processes and parameters to be used to transform a part from its initial state to the final form according to the design specifications. It is a bridge between product design and product manufacturing. The activities of process planning include understanding the part specifications or product design data, selection of job material and tool, setup planning, sequencing the operations within a setup, determination of process parameters for each operation, and generation of process sheets. This paper outlines a method to develop a generative computer-aided process planning system for axisymmetric components for a job shop environment. A decision support system is used to perform semi-structured tasks such as setup planning and establishing precedence relationship among various operations.     

分散网络化制造——香港制造业再发展的模式

提出了一个电子化的生产模式——“分散网络化生产系统”,即充分利用分散于香港和内地之间的中小型企业,合作设计和开发新产品、共享制造资源以及充分利用香港的市场优势。介绍了生产网络的组织结构、管理结构及信息结构的设计和建模。在设计和实施这些模型过程中所积累的经验将为大规模推广分散网络化生产系统的动作提供良好的基础。     

简介虚拟制造中的网络虚拟现实技术

介绍了网络虚拟现实建模语言（VRML），VRML具有动态对象描述和超链接、通用性、扩展性、易实现性等特点。VRML浏览器和生成VRML文件的工具广泛使用于多种平台的计算机，是虚拟制造VM与虚拟设计中的网络虚拟现实技术的基础。     

制造自动化中物流系统设计策略研究

在制造自动化系统（FMS、CIMS等）中,物流系统的设计必须满足整个制造系统的要求,设计策略直接影响物流系统,以至于整个制造系统的效果。本文从制造自动化对物流系统要求出发,提出了物流系统总体设计及各组成部分设计的策略,并分析了相关因素对物流系统设计的影响。     

A web-based advisory system for process and material selection in concurrent product design for a manufacturing environment

This paper reports the work of selecting suitable manufacturing processes and materials in concurrent design for manufacturing environment. In the paper, a fuzzy knowledge-based decision support method is proposed for multi-criteria decision-making in evaluating and selecting possible manufacturing process/material combinations in terms of the total production cost. Based on the proposed method, a prototype Web-based knowledge-intensive manufacturing consulting service system (WebMCSS) with the client-knowledge server architecture is developed to help designers/users find good processes and materials while still at the conceptual level of design. The system, as one of the important parts of an advanced design for manufacturing tool, is a concept level process and material selection tool that can be used as both a standalone application and a Java applet freely available via the Web. Interlinked with Web pages of tutorials, and reference pages explaining the facets, fabrication processes and material choices, the system performs reasoning and calculations using the process capability and material property data from the remote Web-based database and knowledge base that can be maintained and updated via the Internet. The use of the system is illustrated with an example.     

面向全球制造环境的先进制造使能技术

动态联盟企业的组织模式,联盟企业间的动态伙伴关系,动态联盟的群体决策支持系统,动态联盟的组织运行和经营管理技术是敏捷企业的主要研究内容,并行设计技术主要同向球制造网的产品并行设计技术,异地设计与制造技术主要研究异地设计环境下产吕数字化建模及数字化定义,分布式数字化装配技术,工装数字化设计及工装数字化装配技术,虚拟制造与制造过程仿真技术,支持异地设计与制造的计算机协同支持环境（CSCW）等,GM环境下的产品信息集成技术主要研究基于Internet技术的STEP信息集成,分布式产品数据管理技术,基于分布式对象体系的信息集成和全球制造环境网络支持平台,GM环境下的产品开发过程研究的主要研究对象包括产品开发过程建模及分析,仿真工具,产品开发过程管理等。     

Development of an automated progressive design system with multiple processes (piercing, bending, and deep drawing) for manufacturing products

This paper describes the research work involved in developing an automated progressive design system with multiple processes such as piercing, bending, and deep drawing for manufacturing products. This approach to make a progressive, flexible working system is based on knowledge-based rules. The knowledge required for this system is formulated from plasticity theories, experimental results, and the empirical knowledge of field experts. The system consists of three main modules: shape treatment, strip layout, and die layout modules. The system is founded on knowledge-based rules and is designed in consideration of several factors, such as the material and thickness of a product, the piercing, bending and deep drawing sequence, and the complexities of blank geometry and punch profiles. The system then generates the strip layout drawing for an automobile product. The die layout module carries out the die design for each process from the results of the strip layout module. The results obtained using the modules enable the designers of manufacturing products with multiple processes to be more efficient in this field.     

Application of virtual manufacturing in generation of gears

The manufacturing process of gears is fairly complicated due to the presence of various simultaneous motions of the cutter and the job. In this paper, an attempt is made to generate meaningful design data for spur and helical gears and the corresponding rack form cutter necessary for the manufacturing. Using this information, solid models for the cutter and blank are developed and finally gear-manufacturing processes are simulated in a virtual manufacturing environment. The user has the option to choose between design and manufacture mode at will. The integrated process may also help to develop an optimized product. For better understanding of the operational principle, an animation facility in the form of a movie is included in the package.     

面向虚拟雕刻设计的五轴快速加工设备研制

介绍了一套自行研制的面向虚拟雕刻设计的五轴加工设备.论述了设备机械结构的设计方法、数控装置的开发思想和功能,以及与虚拟雕刻设计平台的接口.试验显示该设备能与虚拟雕刻设计平台结合实现产品外形的五自由度立体雕刻.     

Real-time quality monitoring and control system using an integrated cost effective support vector machine

The quality monitoring and control (QMC) has been an essential process in the manufacturing industries. With the advancements in data analytics, machine-learning based QMC has become popular in various manufacturing industries. At the same time, the cost effectiveness (CE) of the QMC is perceived as a main decision criterion that explicitly accounts for inspection efforts and has a direct relationship with the QMC capability. In this paper, the cost-effective support vector machine (CESVM)-based automated QMC system (QMCS) is proposed. Unlike existing models, the proposed CESVM explicitly incorporates inspection-related expenses and error types in the SVM algorithm. The proposed automated QMCS is verified and validated using an automotive door-trim manufacturing process. Next, we perform a design of experiment to assess the sensitivity analysis of the proposed framework. The proposed model is found to be effective and could be viewed as an alternative or complementary tool for the traditional quality inspection system.

     

交互式虚拟设计与同步制造技术算法与图形系统研究

产品的创意外形设计与快速试制对于更好地满足产品多品种、短开发周期、优美外形、提高市场竞争力等需求具有重要意义,而现有的CAD/CAM和快速原型制造技术在这一方面仍然存在一些不足,这里提出的交互式虚拟设计与同步试制系统利用虚拟现实技术和计算机数字雕刻技术,在交互设计、创意设计、快速试制、材料多样性等方面都有所突破。文章阐述了在设计过程中工作描述、刀具轨迹包络计算、图形布尔运算、以及高速逼真图形显示等关键技术。实际工作设计与制造实验证明所开发的系统技术可行,已经可以进行基本的产品外形设计与同步制造。     

Cost model development using virtual manufacturing and data mining: part I—methodology development

This paper reports on research, the aim of which has been to investigate the use of virtual manufacturing and data mining techniques to automate the identification of manufacturing process time estimating relationships that form the basis of product and process cost models. Such models provide information that is critical to all stages of the product development process and to ensuring that development of cost-effective product design and production methods. Use of virtual manufacturing models and data mining techniques enables the majority of the activities involved in the cost model development process to be automated. Hence, reducing the time and effort required, reducing the current high level of reliance on expert judgment and enabling higher levels of cost detail to be estimated. The research reported, therefore, focuses on the use of virtual manufacturing to generate datasets which are then analysed using data mining to identify suitable cost models for manufacturing processes. Part I, of this two-part paper, describes the development of a model development methodology that makes use of virtual manufacturing models and data mining techniques and uses case study data to validate this methodology. Part II will then examine in detail the effectiveness of alternative data mining algorithms in terms of their ability to develop relationships that are (1) representative of the real causal relationships that exist and (2) provide a high level of estimating accuracy.