Innovative integration techniques between Virtual Reality systems and CAx tools

The efficacy of virtual reality (VR) as a design support technique is widely recognised by industries. However, the efficiency of the routine employment of VR into the product development process (PDP) still finds an obstacle in the poor integration of the tools employed. The use of VR still needs long and quite hard procedures to work effectively; the models have to be converted into a format that is compatible with VR systems and each task requires an effort to prepare the virtual environment or to post-process the results that depend on the complexity of the task. This work analyses some VR applications into the PDP and describes some ideas to effectively support the operator that prepares the virtual environment. These ideas have been tested by developing four software interfaces, able to create an easy data exchange link between VR and other design tools like CAD, CAE and computer aided control engineering (CACE).     

VIRTUAL DESIGN OF A NEW TYPE OF HYDRAULIC SUPPORT

Using virtual reality to design a new type of hydraulic support is discussed. That is how to make use of the virtual design to develop coal mining machine in practice. The advantages of virtual design are studied and the simple virtual reality system is built. The 3D parts and elements of hydraulic support are modeled with parametric design in CAD software, then exported to VR environment, in which the virtual hydraulic support is assembled, operated and tested. With the method, the errors and faults of design can be fined easily, many improvements are made and the new hydraulic support is developed successfully.     

面向大型复杂产品的虚拟装配技术研究

针对大型复杂产品在装配生产组织形式、人的参与程度、装配工艺流程的优化、装配人员培训和示教等方面的特点,分别进行了虚拟装配关键技术的研究。重点探讨了考虑人体活动的新型虚拟环境技术、CAD系统和虚拟装配系统的数据集成技术、装配工艺的生成及其优化技术、工艺文件生成和现场示教技术等4个方面。最后给出了开发的虚拟装配原型系统在某型号复杂产品中的应用实例。     

基于虚拟现实技术的原型设计机理研究

把虚拟现实技术与ＣＡＤ设计环境结合起来,通过将人引入概念设计回路,提出了基于约束的面向对象建模方法,形成了基于虚拟现实技术的原型设计系统ＶＲＰＳ,并探讨了系统的组成和实施机理。比较真实地反映了人在产品设计行为中的思维过程,从而克服了传统ＣＡＤ系统的多种缺陷。     

基于虚拟现实技术CAD系统的研究

在CAD系统中引入虚拟现实技术进行设计是当前CAD系统的发展趋势之一，可以为设计人员提供自然、逼真、多感知的设计环境，从而大大提高设计的效率和质量。在介绍传统CAD系统的基础上，分析了其存在的局限，重点介绍了虚拟现实技术的有关概念，基于虚拟现实技术CAD系统的提出、特点以及目前的研究应用现状。     

虚拟环境下基于舒适性的客车内饰设计

虚拟现实环境下基于舒适性的客车内饰设计,是客车全新内饰设计方法,虚拟现实提供沉浸、真实的设计环境,拓宽了设计人员的视野和想象空间;舒适性工程则强调“以人为本”的设计理念,本文结合目前两种最前rgo人体模型的基础上定制符合中国人的人体模型,进行客车的内饰设计,整个设计环境在虚拟环境中进行,“人”沉浸在虚拟的样客车中,设计并和虚拟客车交互,研究驾驶员的可及性、视野以及乘坐舒适性等,使用户可以感受到虚拟原型的演变和舒适性的演变,大大提高了设计的成功率。     

A solution to integrate computer-aided design (CAD) and virtual reality (VR) databases in design and manufacturing processes

The use of virtual reality (VR) techniques in industry is subject to very high expectations, as VR has emerged as a popular technology for computer-human interfaces in order to master the shortcomings of CAD systems. 3D CAD models provide a natural way of sharing design information among participants in the production process. VRML is a tool specifically designed for creating 3D virtual worlds on the Web, where these synthetic worlds can give us the ability to visualise objects and navigate the virtual world. This paper describes a system for VRML model visualisation that enables changes in the configuration file, which is written in XML, and that automatically reviews the model including the functional behaviour. From the evaluated VRML model, the connection to a PDM system is provided with a list of elements and their material properties.     

基于Internet的虚拟资源动态集成技术研究

分布式虚拟制造系统必然会遇到应用环境不确定，工具集不确定的问题，为了完成各种虚拟制造任务，需要动态集成分布在在Internet上的各种工具集，为此，提出了虚拟资源动态集成的概念，并将其作为分布式虚拟制造系统的实现模式。通过建立虚拟资源动态集成环境，形成“虚拟资源集市”，支持各种虚拟制造的工具集注册、动态响应、即时组合及协调运地。研究了虚拟资源的信息获取与操作，基于多代理系统的动态集成环境的协调与控制，基于STEP的模型数据转换等关键技术，给出了系统框架及实现模型，它可实现分布在Internet上的各处产品设计，分析，与仿真工具的远程协同，为分布式虚拟制造系统提供支持，满足了广大中小企业对虚拟制造的需求。     

基于虚拟现实的自动加工过程实验仿真系统的平台设计

迅速发展的互联网和虚拟现实技术使虚拟实验的实现成为可能。在集虚拟现实最新相关信息的基础上，这里提出基于虚拟现实的自动加工过程实验仿真系统的平台设计方案。以自动生产线为对象，文中主要阐述定制仿真实验体系构架的策略，包括：Java语言和VRML为宿主语言的选择；VRML编程与UG软件相结合的虚拟设备场景建摸方法；增强Web服务器动态交互功能的ASP、HTML、Java Applet混合应用;确保管理模块实现系统动态数据库访问和数据显示的Web服务器与数据库管理系统的组合。研制的原型系统表明，该方案所确定的策略是可行的，并能达到预期的效果。     

面向虚拟装配的装配信息自动提取技术的研究与实现

针对商品化CAD系统与虚拟装配系统之间装配信息的转换问题,根据CAD系统中装配信息的表达形式,提出了一种获取装配信息的算法,实现了Pro/E中装配信息的自动提取,并依据Pro/E中装配信息的数据结构和虚拟装配系统的功能要求,设计了一种适用于虚拟装配系统的装配数据结构,较好解决了Pro/E与虚拟装配系统之间的装配信息集成问题,提高了虚拟装配的效率。     

基于并行工程的汽车部件CAD系统

主要研究了并行设计在汽车部件ＣＡＤ系统开发方面的应用。将所要设计的汽车部件在计算机上模拟为一个三维的完全数字化的实体模型,使设计、分析计算、装车检验、工业造型作为一个并行的工程来研究;利用人机工程、动态仿真、虚拟装配等关键技术,克服了传统的设计方法设计周期长、成本高、产品质量低等方面的弊端,使汽车部件的设计符合现代化设计的潮流。     

A new type haptics-based virtual environment system for assembly training of complex products

Virtual reality (VR)-based assembly training has been an interesting topic for the last decades. Generally, there are two shortcomings for nowadays virtual assembly training systems. One is that the operators cannot move around the virtual environment in a natural way as people activity in the real world: they are constrained in a fixed position or can only move in a limited space. The other is that most of the virtual assembly training systems are based on geometry constraint modeling only, which lacks haptics feedback. A new type haptics-based virtual environment system for assembly training of complex products is described in this paper. A new low-cost motion simulator is designed and integrated with the virtual environment to realize free walking by human. An automatic data integration interface is developed to transfer geometry, topology, assembly, and physics information from a computer-aided design system to a VR application, and a hierarchical constraint-based data model is rebuilt to construct the virtual assembly environment. Physics-based modeling and haptics feedback are undertaken to simulate the realistic assembly operations. The application examples and evaluation experiments demonstrate that both motion simulator and haptics have great value for training of assembly processes.     

基于SolidWorks-VRML实现工业机器人在虚拟环境中建模

虚拟设计是CAD研究的重要内容.本文介绍了虚拟现实技术(VR)和虚拟现实建模语言(VRML),并结合工业机器人虚拟现实模型开发的实际,探讨了基于SolidWorks-VRML 建立三维产品虚拟模型的建模方法和原理,最后给出了虚拟工业机器人模型实例.     

基于变量化设计的仪表参数化零件图库的开发及应用

利用以变量化设计为指导思想的软件I DEAS作为开发平台 ,对仪表产品造型零部件图库的设计技术进行了研究 ,建立了基于变量化的尺寸关联驱动的仪表参数化图库 ,为快速实现仪表产品造型虚拟原型逼真设计、系列产品的开发提供了快捷可行的方法。     

基于Pro/E的虚拟设计与制造环境的研究与开发

虚拟制造技术是多个学科领域知识的综合集成与应用，计算机仿真，建模和优化技术是虚拟制造的核心与关键技术。依据虚拟制造的思想，结合成熟的CAD/CAM产品和虚拟现实技术，构建了一个集成的虚拟设计与制造环境，讨论了各模块的功能以及系统开发的关键技术和开发环境。创建了原型系统，对虚拟制造技术的应用进行了初步探索。     

Virtual plastic injection molding based on virtual reality technique

Virtual reality (VR), as a new technology, is integrated with software systems for engineering, design, and manufacturing. The integration has given a new impetus to the field of computer-aided engineering. This paper presents a research effort aimed at creating a virtual plastic injection molding (VPIM) environment, which is designed and implemented based on techniques such as VR, multidiscipline simulation, and scientific visualization. The VPIM system includes two parts: designing in VPIM and evaluation in VPIM. It is the first system to scrutinize virtual prototype mock-ups of new products, machines and production processes in interactive graphic simulation. During the evaluating phase, coupled to appropriate computer-based reasoning and decision-support tools and driven by data from the real manufacturing environment, a realistic impression of the process of plastic injection molding and manufacture can be achieved and can be changed interactively, and it is possible to thoroughly examine the planned system and eventually detect and remove any defects and inadequacies. The construction approach and key techniques (FEA, virtual assembly, stereoscopic display, a triangulated boundary-representation of an approximating polyhedron, collision detection, etc.) of the system are described in detail. The overall system is a powerful new approach for highly relevant industrial application of VPIM which focuses on the construction and assessment of alternate manufacturing sequences and mold design in an early design stage. Improvement of the design and manufacturing process will lead to better design and reduced development time and cost.     

Development of an authoring framework for the simplified customization of PDM systems

Given that the amount of product data in firms is explosively increasing, a PDM system for effective data management is considered indispensable for product development. However, considerable time and specialized human resources are needed to customize a generic PDM system for satisfying the specific requirements of individual firms. To overcome this problem, we propose the use of UML object models in a PDM authoring framework. A PDM authoring framework, which provides authoring functions for the effective customization of PDM systems, will reduce the need for the intervention of PDM specialists in the design of the object models of the PDM system. We describe how a PDM authoring framework may be designed by using UML object models, and show how model-oriented application development (MOAD), in conjunction with the PDM authoring framework, can be used to build object models into a PDM system. Furthermore, we confirm the value of the framework by evaluating its performance under several conditions. This paper was recommended for publication in revised form by Associate Editor Dae-Eun Kim Inho Song is a postdoctoral associate in the Department of Mechanical Engineering, Carnegie Mellon University, USA. He received the Ph.D. degree in Mechanical Engineering from Hanyang University, Seoul, Korea in 2007. From 2002 to 2007, he served as a CAx team leader of the INOPS Company (CIES R&D Center), Seoul, Korea. He has developed the sketch-based CAD system for an automotive company. His research interests include collaborative design, sketch-based CAD, geometry translation, geometry compression, product data exchange, PDM/PLM, digital manufacturing, and virtual reality. Jeongsam Yang is an assistant professor in the Department of Industrial & Information Systems Engineering and is leading the CAD laboratory() at Ajou University. He worked at Clausthal University of Technology (Germany) as a visiting researcher and the University of Wisconsin-Madison (USA) as a postdoctoral associate. He obtained his Ph.D. in mechanical engineering in 2004 at KAIST. His current research interests are product data quality (PDQ), VR application in product design, product data management (PDM), knowledge-based design system, and STEP. Peom Park is a professor in the Department of Industrial & Information Systems Engineering and is leading the Human Technology Research Center and Human Factors/HCI laboratory () at Ajou University. He worked on HCI and Telecommunication system at ETRI as a senior researcher. He obtained his Ph.D. in Industrial and Manufacturing Systems Engineering at Iowa State University on 1992. His current research interests are uT applications, u-Healthcare/Telemedicine, Telematics and Ergonomic/Safety Design.     

甘蔗收获机械可视化虚拟设计的集成框架研究

介绍了甘蔗收获机械可视化虚拟设计集成框架建立的基本思路，详细分析了甘蔗收获机械可视化虚拟集成设计开发的流程及可视化虚拟集成智能设计开发环境建立的方法，为甘蔗收获机械集成化、系列化的设计开发提供可靠的基础和依据。     

三维CAD/CAE一体化的参数化动态有限元建模

提出了一种基于CAD参数化技术与CAD／CAE一体化技术的参数化动态有限元建模方法，该方法解决了三维实体有限元建模中几何模型的描述与驱动、参数联动、模型自动更新等一系列问题，为先进的参数化有限元分析与优化设计提供了关键技术基础；阐述了三维参数化动态有限元建模方法中的若干关键技术，包括具有典型意义的基于AutoCAD／MDT二次开发环境ObjectARX的CAD／CAE集成方法、复杂三维组合曲面网格全自动生成算法、复杂三维实体的四面体网格全自动生成算法、面向对象的有限元模型描述方法，以及有限元模型的参数驱动方法等；建立了一个三维参数化形状优化设计应用原型系统。     

A web-based 3D virtual technologies for developing product information framework

Information technologies and the web are challenging, and changing theway industry works. It is believed that web-based 3D interface can be applied to strengthen the interactive visualization and manipulation of products. In this research, a web-based 3D virtual technologies for developing product information framework is applied in automotive electric system. It is very convenient to share with different partners (e.g., co-designers, manufacturers, customers, etc.) via the web for viewing the aesthetic functions, and verifying its related design functions. The overall procedures are listed: First, build CAD models of automotive electric system (including assemble parts and their components) through CAD system, then store them in a relational database. Second, transforming the CAD models users click into virtual reality modeling language (VRML) objects, it can be visualized graphically and animated interactively using a web browser with a VRML plug-in. Finally, operate the VRML objects by Java Language for the different purposes. Due to the technologies that are applied, many interactive modes are generated in cyberspace. Displaying the exploding process of 3D assemble part on the browser, assigning any component of assemble part through the mouse chick directly to display design details, e.g., dimensions, tolerances, datum planes, material, other references, etc. by retrieving the corresponding data from database, and building 2D projected views automatically follow the 3D viewpoint that users assign.