基于XML的CAD系统和虚拟装配系统之间的数据转换

针对计算机辅助设计系统和虚拟装配系统之间的模型转换问题,提出了基于特征的统一的产品层次信息模型,采用XML中性文档和三角面片模型文件,通过信息分解的方法,分别将在产品建模系统中建立的产品层次信息模型中的装配信息和几何拓扑信息与三角面片信息通过数据转换接口转换到虚拟装配系统中,并在虚拟装配系统中通过映射关系进行模型重构,较好地解决了计算机辅助设计系统和虚拟装配系统之间信息共享的问题,通过实例验证了研究成果的可行性。     

从CAD系统到集成虚拟装配环境的数据转换研究

为了完成产品模型从计算机辅助设计系统到集成虚拟装配环境的数据转换,提出了信息提取模型转换法,将计算机辅助设计系统中的模型数据转换分解为信息提取和模型转换两部分,通过计算机辅助设计系统的二次开发和模型转换,得到集成虚拟装配环境所需的模型数据信息。以圆锥破碎机的进料机构为虚拟装配对象,在集成虚拟装配环境中对数据转换结果进行了验证,结果表明,用信息提取模型转换法获得的转换数据完整准确,转换效果良好。     

CAD系统与虚拟装配系统间的信息集成技术研究

针对商品化计算机辅助设计系统与虚拟装配系统间的数据转换问题,提出了一种虚拟装配环境下的零件信息层次表达结构模型,该模型由面片层、几何层、特征层和零件层组成;给出了虚拟装配环境下零件信息模型的重构方法,通过对计算机辅助设计系统中零件信息的提取和虚拟装配环境中零件信息的重构,较好地解决了商品化计算机辅助设计系统与虚拟装配系统之间的数据集成问题;建立了虚拟装配原型系统,验证了研究结果的可行性。     

虚拟装配设计系统的研究

着重描述了在虚拟装配的过程中,所涉及到的装配建模、模拟信息的预处理、装配“预计划”、虚拟装配设计和虚拟装配过程评价等关键技术。     

基于WEB的虚拟装配信息管理系统的设计与实现

利用当今最流行的.NET技术开发了虚拟装配信息集成管理系统.此系统是面向Web的集成服务器应用系统,采用B/S三层网络体系结构,用户只需要IE浏览器就可以登陆本系统,通过运行服务器上的应用程序来对零部件信息数据库进行查询或利用其信息进行在线装配.也可对零部件库进行综合管理,实现信息集成与共享.     

传动系统CAD平台中数据处理方法研究

在传动系统CAD平台的设计中，涉及大量的设计数据和标准规范，从设计计算到图形输出都是以数据处理为中心来组织的。这里结合机械传动CAD系统设计过程的具体要求及其数据特点，采用了程序化和数据文件的方式来管理数据。重点论述了交互式输入、程序化处理和一维数表、二维数表的数据文件管理方法，并基于AutoLISP语言实现了整个CAD系统的数据管理。达到了数据利用率高、程序结构性好、模块性强的目的,减少了开发过程的复杂性。     

虚拟装配工艺设计技术研究与应用

阐述虚拟装配工艺设计技术内涵及其体系结构,深入分析其所涉及的CAD系统与虚拟现实系统间的数据转换、碰撞检测技术、装配规划与仿真以及装配运动导航与准确定位等关键技术,并应用该技术,以商品化CAD系统Pro/E为建模工具,在VC与WTK平台及ORACLE数据库的支持下开发了一个虚拟装配工艺设计原型系统HIT-VAPD,实现了虚拟现实环境下的产品装配工艺规划与设计.实际应用表明,该系统可显著提高装配工艺设计效率,减少设计缺陷.     

虚拟装配技术在自动扶梯设计中的应用

虚拟制造是一种新兴的先进制造概念和理论,虚拟装配是虚拟制造研究领域重要的研究分支.利用三维建模软件Solid Works对自动扶梯进行参数化建模,完成了虚拟装配.实现了试制样品前的干涉检查、运动配合检查及物理模拟.     

虚拟式振动测试系统的研发和应用

介绍应用虚拟仪器技术根据教学与实验研究的实际需要,自定义功能研究开发的"虚拟式振动测试系统".该系统只需投入少量的硬件成本,即可集成测试系统,实现强大的分析功能,现已成功应用于教学与实验研究中.     

CAD与CAPP之间信息共享的实现方法

实现CAPP与CAD之间的信息共享、无缝连接，一直是CAPP系统开发过程中的一个难点。这里对该问题进行了研究与探索，并介绍了一种关于怎样获取CAD图纸界面上零件总体信息及将CAPP系统处理后的数据库信息写到CAD图纸界面上的方法。     

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.     

CAD与CAPP集成中数据文件实时修改的一种新方法

基于特征拼装CAD／CAPP集成系统,提出了一种实时修改CAD数据文件的新方法。文中采用实时修改技术,通过数据文件和数据字典文件,将数据读入二维数组中。在修改零件信息时,可直接实时修改数据表单中的零件信息,其修改简捷、方便。该方法巳成功地运用于港机轴类零件集成之中。其基本设计思想对正在从事研究基于特征的CAD／CAPP集成系统有一定的参考价值。     

A novel optimal assembly algorithm for haptic interface applications of a virtual maintenance system

A virtual maintenance system in a virtual environment can be used to simulate a real-world maintenance system. The efficiency of the simulation depends mainly on the assembly/disassembly task sequence. During simulation, path planning of mechanical parts becomes an important factor since it affects the overall efficiency of the maintenance system in terms of saving energy and time. Therefore, planners must consider the path-planning factors under constraints such as obstacles and the initial/final positions of the parts, as well as the assembly sequence such as number of gripper exchanges and direction changes. We propose a novel optimal assembly algorithm that considers the assembly sequence of mechanical parts and the path-planning factors for a virtual maintenance simulation system. The genetic algorithm is used to determine the optimal sequence of parts to minimize the numbers of gripper exchanges and direction changes, as well as find a repulsive force radius by using the potential field method to generate the shortest optimal distance for transferring each part during the assembly operation. By applying the proposed algorithm to a virtual maintenance system, users can be haptically guided to the optimized assembly solution during mechanical parts assembly operations. This paper was recommended for publication in revised form by Associate Editor Jong Hyeon Park Christiand received a B.Eng. degree in Mechanical Engineering from University of Indonesia in 2006. He then went on to receive his M.Eng. from Gyeongsang National University in 2008. He is currently a member of engineering staff at Electronics and Telecommunication Research Institute (ETRI) in Daejeon, Korea. Jungwon Yoon received the B.S. degree in precision mechanical engineering in 1998 from the Chonbuk National Univ., Korea, and the M. S. degree in the Department of Mechatronics in 2000 from Gwangju Institute of Science and Technology (GIST), Kwangju, Korea, where he received the Ph.D. in 2005. He had worked as a senior researcher in Electronics Telecommunication Research Institute (ETRI), Daejeon, Korea, and a visiting researcher at Virtual Reality Lab, the Rutgers University, U.S.A, from 2001 to 2002. In 2005, he joined the School of Mechanical & Aerospace Engineering, Gyeongsang National University, Jinju, Korea, where he is currently an assistant professor. His research interests include virtual reality haptic devices & locomotion interfaces, and rehabilitation robots.     

某型航空发动机装配过程虚拟仿真应用

在复杂工业产品制造的工艺准备阶段,借助于数字化三维虚拟仿真技术进行工艺设计和优化是十分必要的.针对中国首次研发的某商用航空发动机,基于中国自主开发的VR-Layout虚拟工厂建模与仿真平台,开展发动机本体装配、转子平衡和外部装配3个工艺过程的三维虚拟仿真建模和分析评估工作,实现了工艺文件的可视化展示和验证、工装干涉检查、工位器具的补充设计.该项工作不仅为后期工艺文件的持续优化初步建立了软件平台,也为其他制造产品的三维虚拟仿真设计提供了技术参考和流程经验.     

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.     

Research on method of constraint conversion in feature-based data exchange between heterogeneous CAD systems

Data exchange between heterogeneous CAD systems is the key problem in the field of CAD, and the popular solution to this problem is a feature-based method. Aiming at keeping the consistency of design intent in data exchange between heterogeneous CAD systems, this research focuses on the method of constraint conversion. First, two kinds of basic feature transformation ways are summarized, and this is the foundation of constraint conversion. Second, a novel identification of geometric elements based on the improved geometric certificate is proposed, and the identifier of geometric element is used to recognize the acting object of constraint. Third, the principles of constraint conversion are put forward, and the method of constraint conversion for a single feature is proposed according to the principles. Fourth, an algorithm of constraint conversion for the whole process of CAD data exchange is designed. Finally, the contrast experiment of CAD data exchange is completed, and the result of the experiment shows that the approach mentioned above is effective. This paper was recommended for publication in revised form by Associate Editor Dae-Eun Kim Sun Wei is a professor and the deputy dean of school of mechanical engineering at Dalian University of Technology. His research interests include knowledge-based product digital design, computer supported collaborative design, analysis and optimization of product. He received a BS, a MS and a Ph.D in mechanical manufacturing and automation from Dalian University of Technology, P. R. China. Ma Tie-Qiang is a Ph.D. candidate in school of mechanical engineering at the Dalian University of Technology. He received a BS and a MS from Dalian JiaoTong University P. R. China. His research interests include computer graphics & computer aided design, product data management, computer supported collaborative design. Huang Yu-Jun is a graduate in School of mechanical engineering at the Dalian University of Technology. He received a BS from Wuhan University of Science and Technology P.R. China. His research interests include product data exchange and computer graphics     

虚拟装配中几何精度可视化及其实现技术

针对公差设计过程中产品几何精度信息的表达缺乏直观性和可感知性的问题,在分析几何偏差、公差域及公差等级等精度信息的基础上,提出基于标注模式和颜色感知的几何精度可视化表达方法。通过解析装配系统中的几何模型、精度模型及三维标注模型,建立几何精度的可视化模型以及精度信息与颜色值的映射关系,解决了可视化模型与几何模型、三维标注模型等的关联问题。在此基础上,借助虚拟环境相关渲染技术,实现了几何偏差或误差相对于上下偏差限的几何精度相对可视化,以及反映公差等级的几何精度绝对可视化,提高了几何精度信息在虚拟装配系统中的可感知和可交互性。相关模型和算法已在原型系统中得到实现,并通过实例进行了验证。     

基于XML的CAD产品信息集成技术研究和实现

异构数据源的交换和共享是虚拟产品开发中信息集成的核心.采取基于XML的方式进行CAD产品信息集成,具有结构清晰和互操作性强的优点.该文针对汽车模具产品开发的应用背景,实现了基于XML的CAD产品信息数据共享,为汽车模具虚拟产品开发系统中的其他分系统提供了快速有效的产品信息访问.     

面向虚拟装配的信息获取与应用

介绍了面向虚拟装配的信息获取和重用方法,该方法可以实现虚拟装配环境快速构建和对虚拟装配系统的数据支持。首先建立虚拟装配系统的信息模型,实现了信息源与虚拟装配系统之间的联系。根据信息源的不同,将信息源分成基于计算机辅助设计系统、基于用户输入和基于装配规划模块三种方式进行获取,并将获取的各种信息应用到虚拟装配系统的装配规划和装配验证等功能模块中。通过实例,对虚拟装配信息获取和应用流程进行了说明。     

基于虚拟装配技术的胶球清洗系统收球网的设计

把虚拟装配技术用于胶球清洗系统收球网的设计过程中,实现了收球网的虚拟装配,完成了收球网的动态模拟。