Development of a prototype customer-oriented virtual factory system

Current Computer integrated manufacturing/Enterprise Resource Planning (CIM/ERP) systems require harmony and communication between humans and facilities. A user’s preferences should also be considered in CIM/ERP systems. Virtual factory (VF), also known as virtual manufacturing (VM), systems can fulfill the requirements of current CIM/ERP systems. A VF system simulates virtual production in a virtual factory environment on the computer system which allows optimization prior to going into production. In this paper, we defined a VF system as a pre-analyzing system for designing, engineering and manufacturing a product in the enterprise system of the real world. The objective of this paper is to design a VF system and to develop a prototype system that the customer can participate in and be satisfied with. We selected a telephone as a sample product for the VF system. The VF system consists of four subsystems: virtual product ordering, design, manufacturing, and CIM/ERP interface. The prototype system aims to develop a virtual product ordering and design system.     

Production engineering-oriented virtual factory: a planning cell-based approach to manufacturing systems design

In the traditional process of designing a manufacturing system, a sequential approach treats each of the design steps individually, without considering the requirements of concurrent design activities. The lack of systematic and concurrent consideration of the interactive impact of design decisions leads to repeated and excessive changes in the design and process. To resolve this problem, this research develops a production engineering-oriented virtual factory – a planning cell-based manufacturing systems design approach. The manufacturing systems design process based on a planning cell is reengineered according to the concept of concurrent engineering. The process modeling of a production engineering-oriented virtual factory is proposed at generic and particular levels. An illustrative example of an engine assembly plant demonstrates the effectiveness of the new approach.     

基于虚拟样机技术的无级变速器设计与研究

无级变速器(CVT)能够在一定范围内连续实现速度改变,适用范围宽,应用前景广。利用虚拟样机技术实现无级变速器的设计与研发,具有研发周期短,成本低,并且能够实现产品全生命周期管理。通过在多体系统优化仿真软件RecurDyn中建立CVT虚拟样机模型进行运动学和动力学分析和仿真,全面了解CVT各方面性能,并将仿真结果与理论计算结果对比,从而证明虚拟样机技术的可行性和先进性,并具有很大的推广价值。     

基于虚拟样机技术的变幅机构液压系统的仿真研究

论述了虚拟样机技术的概念及虚拟样机软件ADAMS的主要特点,给出了在ADAMS环境下进行虚拟样机设计工作过程,并建立了某起重设备变幅机构的虚拟样机模型,并对其液压系统进行了仿真分析。     

自装卸系统虚拟样机设计与仿真分析

根据装卸作业原理,利用SolidWorks软件建立了自装卸系统的三维实体模型,通过其插件COSMOSMotion导入到ADAMS中,实现了自装卸系统虚拟样机的设计;对作业过程进行了仿真和分析.     

Development of Web-based CAM system

In this paper, we present the methods to develop a Web-based CAM system that is capable to dynamically simulate machining processes in solid graphics form through the Internet. Methods include the virtual reality modeling language (VRML) structure to represent the machined workpieces progressively on Web, the definition and storage of workpiece information upon the request of users, the CORBA-based interpretation of NC part programs, and algorithms for efficient machining simulation. Based on these methods, an Internet-based CAM system is implemented at http://isd.korea.ac.kr. Using the Web-based CAM system, public users can simulate machining processes by for their own NC part programs.     

综述基于ADAMS的液压仿真虚拟样机技术

当前液压驱动在整个机械工业领域得已广泛应用．现代市场竞争对其提出了更高更多更快更省的要求．虚拟样机技术作为此阶段应运而生的应用技术在液压控制分析中显得尤为重要。文章综述基于ADAMS的液压虚拟样机技术在机械系统仿真方面的优势和具体操作;并阐述其功能拓展．利用其提供的与其他分析软件的接口来进行互作、协调、统一．最终实现对整个机-电-液系统虚拟实现仿真分析。     

空间转镜扫描机构的虚拟样机模型建立及动平衡仿真实验

从常用的空间转镜扫描机构出发,利用虚拟样机技术建立此扫描机构在步进扫描、连续高速扫描工况下的虚拟样机模型,并且在虚拟样机模型中进行了动平衡优化设计的虚拟仿真实验,得出该机构在不同工况下轴承的受力情况,最后针对仿真结果进行了验证.     

测试仪器的发展方向--以TCP/IP作为通讯方式的虚拟仪器测试系统

该文对于目前虚拟仪器系统中硬件与计算机的串并口、PC总线、GPIB总线、PXI、VXI和各种现场总线连接方式的基本情况和主要缺点，及其对测试系统的整体性能的影响做了分析，介绍了以TC/IP作为通讯方式的虚拟仪器系统的结构特点、在性价比、拓扑自由度、开放性和互操作性、系统稳健性等方面的优势以及发展展望。     

面向企业异地协同设计与制造的MVPN的研究

从企业对异地协同设计与制造的具体要求出发，结合VPN技术、产品生命周期管理(PLM)技术和制造业信息化技术各自的特点和优势，创造性地提出了面向企业异地协同设计与制造的制造虚拟专用网(Manufacturing Virtual Private Network，MVPN)理论，有效解决了资源共享、数据转换、数据同步以及数据传输安全等瓶颈问题。最后，通过上海大学MVPN(SHU—MVPN)的试运行，验证了该理论的可行性，为制造企业适应激烈的市场竞争和进行产品创新做了一些有益的探索。     

A knowledge-based system for operations management in a small to medium sized enterprise

In recent years, there has been an increasing interest in the mechanisms and structure of scheduling in a computer-integrated manufacturing (CIM) environment. This has led to the development of new scheduling models, such as Petri nets, time-augmented Petri nets, fuzzy scheduling models and neural net scheduling models. A fundamental objective of any scheduling system is event synchronisation and optimisation of command, communication and control C³ between each active node of the overall CIM structure. CIM scheduling can be regarded as a nonlinear dynamic control process, whereby, the feed forward or feedback elements are the scheduling priorities that enable the manufacturing organisation to remain within a steady-state profit margin. However, in each different hierarchy level of the organisation, randomness phenomena in the C³ environment can be observed, i.e. events in a particular department or organisational level cause a perturbation elsewhere in the manufacturing organisation. Furthermore, these changes are constrained by the framework of rules pre-set by the organisational structure and business corporate strategy. To a first approximation, these cause-and-effect phenomena can be viewed as deterministic changes which may result in deterministic chaos. In this paper, a self-organising compensating information system (SOCIS) is presented. This system is designed utilising knowledge control modelling (KCM) topology with its architecture based on the principles of client-server and a second-order proportional-integral-differential knowledge-based management system (PID-KBMS).     

The application of virtual reality to tasks in manufacturing and assembly engineering

Virtual Reality is a developing technology for which a range of applications are heing explored by different international research groups. This paper describes recent research in the application of Virtual Reality to two important manufacturing and assembly tasks which have a direct influence on the speed of introduction of new products. The tasks are the production of planning documentation for assembled products and the design and planning of the cable harnesses which form part of all electro-mechanical assemblies. The research completed so far demonstrates the potential of Virtual Reality, even at its current stage of technological development, to make a significant contribution in both these cases.     

Geometric and radiometric characteristics of a prototype surveillance system

This paper reports the research findings regarding the quality of the captured video of a prototype Near-Infrared imaging system which was developed for night-time surveillance. The prototype required the incorporation of a 3D optical stereo adapter and a set of external near-infrared filters onto the optics of a conventional video camera. The study found that the video captured by the prototype was approximately 85% of the original video camera resolution and the radial lens distortion increased from one to approximately two pixels. The distortion was easily reduced to sub-pixel value using suitable image processing techniques. The standard deviation of the 3D measurement between any two facial anthropometric marks was better than 2 mm for all the tested models. The image radiometric quality was sufficient to provide accurate facial landmark identification for three test subjects. The results confirmed that the prototype was suitable for 3D spatial data capture and feature interpretation of crime suspects in court.     

基于虚拟仪器技术的酵母发酵监控系统的设计

本文介绍了虚拟仪器的概念和组成结构，深入研究了运用虚拟仪器开发平台Lab Windows／CVI设计酵母发酵监控系统的方法，并讨论了该系统的硬件结构．软件结构及其功能实现。     

A prototype system of three-dimensional non-contact measurement

A prototype 3D measurement system is proposed in this paper which consists of a 1D laser displacement sensor, a 2D image system and a servo controlX,Y-table. The laser sensor and CCD camera are installed on theZ-axis perpendicular to theX,Y-table. The image-processing system employs the adaptive resonant theory (ART) neural networks to classify the outer shape of the measured object. The edge values of the object are then obtained by using the image processing procedures of sliding, stretching, edge enhancement and binary disposal. The 2D dimensions of the object are searched by employing the Hough theory based upon the edge values. The 3D dimensions of the object are measured and assembled by combining theX,Y-coordinates of the table and the scanning results of the 1D laser for the height of theZ-axis. A 3D plaster model is chosen as the specimen for non-contact measurement to verify the feasibility of this approach. The limitations and resolution of the 3D measurement of this system are discussed.     

基于虚拟仪器的车辆综合传动装置测试系统设计

为提高测试数据采集与处理的自动化和智能化程度,融合虚拟仪器、稳态与动态数据采集技术与办公自动化技术,在Visual Basic平台上自主开发了多参数车辆动力传动测试与故障诊断系统.该系统将多路传统仪器功能模块显示在同一窗口,采用数据库对测试项目、传感器与仪表的配置及标定、设备型号的选择等以适应各类不同功能与规模的测试项目.实现了多参量数据的自动采集,可进行各类数据处理及分析与定制格式试验报告的自动生成.实际应用表明,该系统工作可靠、操作便利.     

基于虚拟主机技术的微机配料系统设计及实现

详细论述了利用虚拟技术构成分散控制的微机配料系统的原理、总体构成及实现方法，并给出应用实例。这种技术在不增加硬件成本的前提下，使系统可靠性大大提高，具有广阔的应用前景。     

基于CIM的励磁系统建模

IEC 61970-301标准定义了能量管理系统(EMS)的应用程序接口(API).公共信息模型(CIM)是这个标准中的重要部分之一,它规定了这类API的语义.但CIM并没有对与同步机紧密相关的励磁系统建模.为了实现励磁系统与能量管理系统的标准化集成,实现"即插即用"式的励磁系统应用,有必要在公共信息模型中建立励磁系统的模型.在对励磁系统进行详细分析的基础上,抽象出励磁系统的模型,通过继承和关联的方式将励磁系统模型与CIM中现有的模型相结合,充分利用CIM中已有的信息,完成了基于CIM的励磁系统详细建模.     

A grid-based scheduling system of manufacturing resources for a virtual enterprise

In this paper, a scheduling system of manufacturing resources for a virtual enterprise is built up based on grid technology. The scheduling system is composed of an exterior grid and an interior grid in the architecture, while the scheduling procedure of manufacturing resources in a virtual enterprise consists of two stages – distributed scheduling and local scheduling. The exterior grid is utilized to implement the distributed scheduling and the interior grid is used to accomplish the local scheduling. This paper illustrates the manufacturing system of a virtual enterprise based on an exterior grid and the manufacturing subsystem of a member enterprise based on an interior grid. Subsequently, the scheduling procedure of manufacturing resources within the virtual enterprise is described for a particular example. Finally, a case of collaborative production of a customized artificial joint (CAJ) in a virtual enterprise is applied to demonstrate the implementation of the scheduling system of manufacturing resources for the virtual enterprise. With grid technology, the efficiency of manufacturing resource scheduling in the virtual enterprise has been improved greatly.     

敏捷虚拟企业环境下伙伴企业产品过程再设计

在敏捷虚拟企业环境下,怎样根据联盟的需要对伙伴企业的产品过程进行重新设计是关系到敏捷虚拟企业实施成败的关键。本文建立了敏捷虚拟企业产品过程设计的基本框架,给出了进行过程再设计的核心过程确定方法,并提出了一些进行过程结构优化的方法。