基于Delphi和VRML的虚拟装配平台的实现

针对目前 CAD软件只生成静态三维装配体 VRML 文件的问题 ,分析了交互式虚拟装配 VRML 文件的事件流程和虚拟产品的顺序装配的机理 ,提取其中可赋值变量 ,利用可视化编程语言 Delphi开发一个实现复杂虚拟装配的平台 ,完成静态 V RML文件到动态交互式虚拟装配文件的自动转换     

基于镜像样机的交互式实车装配平台实现

针对传统装甲车辆研发过程中样车研制周期长、问题追溯困难等不足,在虚拟样机的基础上提出镜像样机的定义,将样车总装过程纳入镜像样机框架,开发了实物在回路的交互式实车装配平台,缩短了装甲车辆总装研发周期,提高了总装质量,实现了总装相关问题的快速追溯。在虚拟样机定义的基础上,给出了镜像样机的定义;在虚拟样机体系框架的基础上,搭建了镜像样机的体系框架;基于镜像样机的体系框架,提出交互式实车装配平台的框架结构,给出了交互式实车装配平台的功能架构和运行机制;按照平台的理论模型,基于Microsoft C#.Net开发环境给出了平台原型实现,达到了预期效果。     

基于VRML-Java3D的交互式装配可视化环境构建

为了实现基于网络的可视化虚拟装配环境,笔者研究了Java3D与VRML相结合的方法。通过Loader接口将VRML造型文件导入到Java3D场景图中,借助Java语言的事件处理模型,并结合Java3D中的Interpolator内插器对象和Alpha对象,实现交互式添加、拆卸、移动和旋转等装配过程。最后以电机中的转子装配为例,给出了一个基于VRML-Java3D的交互式装配可视化环境。     

复杂产品分布式并行协同虚拟装配系统研究

为解决复杂产品异地协同设计中零部件数模验证和装配评审的困难,研究了基于网络的分布式协同虚拟装配技术,提出基于高层体系结构/运行时间框架的分布式协同虚拟装配方案,解决虚拟环境中的用户管理、操作协同和交互式装配操作等问题.以此为基础开发出了支持实时协同交互装配仿真的分布式并行协同虚拟装配系统,并以某汽车部分总成网络协同装配为例验证了该方案.结果表明,该方案可以实现复杂产品设计中的异地协同装配仿真与评审.     

基于VRML和Java的交互式虚拟装配技术研究

虚拟装配是虚拟制造领域研究的热点.阐述了机械零部件虚拟建模流程,研究了虚拟场景与外界交互的手段和方法,通过VRML编程接口 JSAI和EAI与Java的结合,实现了机械部件的交互式虚拟装配仿真,并从产品的拆卸和装配角度出发,以柴油机多缸喷油泵为模型给出了开发过程实例.     

基于XML的可重构装配模型

产品装配模型是实现网络化协同虚拟装配的核心内容。针对网络化协同虚拟装配环境对装配模型的重构与共享的需求,提出了应用XML技术表达与处理可重构装配模型的方法。论述了可重构装配模型的对象结构和XML语言描述,并说明了相应的数据重构和共享的处理方法。为网络化协同虚拟装配系统开发提供了模型方案。     

以Virtools为基的交互式产品虚拟展示技术研究

针对目前电子商务模式中产品虚拟展示现状及特点,提出基于Virtools平台下的交互式产品虚拟展示方法,并以齿轮油泵为例阐述产品虚拟展示的设计制作流程以及各个环节的实现方法,最终在网页上建立交互式的三维产品动态虚拟展示模型,有效地提高数字化产品的信息传达效果。     

基于NX及ICIDO仿真的柴油机曲柄连杆机构装配应用

柴油机曲柄连杆结构主要由曲轴、连杆、活塞等零部件构成,也是柴油机的重要运动件,其装配过程对柴油机工作起到了重要的作用,通过利用NX系统平台对曲轴、连杆、活塞进行三维模型建立,并将模型导入ICIDO可视化虚拟平台进行曲柄连杆机构三维虚拟仿真装配操作,减少产品试制阶段的多轮次实物验证,缩短产品的研发周期。此虚拟仿真装配研究利用NX提供了产品的装配顺序规划、装配路径规划,同时,利用基于ICIDO虚拟现实(virtual reality,VR)实现了对曲柄连杆机构的虚拟仿真装配及对应的干涉仿真装配,为后续整机装配工艺方案规划奠定了基础。     

基于HLA的分布式协同虚拟装配系统研究

针对复杂产品装配设计过程中协同工作的需求,开发了一个面向多用户协同设计的分布式虚拟装配系统(DCVAE).提出了分布式虚拟装配系统体系结构、对协同虚拟装配操作方法进行了研究,基于分布式仿真支撑环境DMSO HLA/RTI,利用实时视景仿真软件开发库OpenGL Performer,实现了DCVAE的原型系统.通过某车型整车协同虚拟装配评审实例,证明该系统可应用于复杂产品的虚拟装配数摸验证.     

基于VRML的机械产品虚拟装配技术研究

简要介绍了VRML语言定义、特点,阐述了机械零部件虚拟建模方法。对虚拟装配流程进行分析,并对产品装/拆运动的表示形式、虚拟装配路径规划及逻辑控制、虚拟装配过程中的碰撞检测方法等关键技术进行了研究,提出了产品装/拆运动12元组表示形式。最后,通过对机械产品交互式虚拟装配进行实例仿真,验证了该技术的可行性和合理性。     

基于EON的网络虚拟装配技术的实现

基于网络的相关虚拟装配技术,使用EON Studio软件,通过三维产品建模、虚拟装配、网络发布等一系列步骤,实现了基于网络的人机交互虚拟操作,为各种产品的虚拟装配及虚拟展示探索出了较好的思路与方法。     

Constrained behavior manipulation for interactive assembly in a virtual environment

Interactive assembly based on virtual reality offers users an opportunity to interact with a virtual prototyping rather than a physical one and to validate assembly performance of products in a realistic way. Such evaluations could be available very early in the product development process ahead of any physical prototyping. The reduction or elimination of physical prototyping needed for assembly performance validation can substantially shorten the product development cycle and reduce development cost. Although virtual reality technology provides users an intuitive and immersive 3D interactive interface, it tends to be inaccurate because humans have difficulty in performing precise positioning tasks. Therefore, it is necessary to implement effective motion manipulation for assembly operations so that users can perform precise positioning efficiently in virtual assembly systems. This paper presents a constrained behavior management approach that realizes assembly relationship recognition, constraint solution and constrained motion for interactive assembly in a virtual environment. A constrained behavior manager (CBM) has been developed and applied in virtual assembly systems. Test cases confirm that constrained behavior manipulation proposed in this paper not only increases the efficiency of assembly relationship recognition, but also facilitates assembly interaction in a virtual environment.     

Interactive assembly tool planning based on assembly semantics in virtual environment

Assembly tool planning in virtual environment remains to be a challenge because of the complexity and variety in tools configuration and manipulation. In order to solve the problem, an interactive assembly tool planning based on assembly semantic model is proposed. After detailed analysis on assembly tool planning in virtual environment, an improved assembly semantic model is represented, and a new assembly tool model is developed based on assembly semantic model. With the help of assembly semantic processing method, such as recognition, solving, navigation and so on, a series methods including assembly tool selection, orientation, manipulation are proposed for interactive assembly tool planning in virtual environment. Finally, tightening tool planning for connecting rod caps of auto engine assembly line demonstrates the feasibility and validity of presented methods.     

雷达结构交互式虚拟装配系统研究

文中针对雷达结构传统装配设计中存在的效率低、一次装配成功率不高等问题,提出了一种基于虚拟现实技术的交互式虚拟装配系统构建方案。该系统集成交互式外设在不需要任何雷达实物的情况下,完全在虚拟环境下通过用户的自然操作,实现雷达结构装配的全过程。文中介绍了系统中虚拟装配功能模型的构建方法,重点分析了虚拟手在系统中的动作实现过程,阐述了雷达结构装配仿真规划的方法,最后还介绍了原型系统的开发过程和系统功能的实现。     

A web-based virtual system for turn-milling center

This paper presents a three-dimensional, web-based, interactive simulation system for turn-milling center. To overcome the disadvantages of transferring files over the Internet and depending on expensive computer-aided design (CAD)/computer-aided manufacturing (CAM) softwares, the system is developed by virtual reality modeling language (VRML)/JavaScript interaction. The system files produced by machining simulation have small size, and could be transmitted on the web easily. Firstly, a dynamic interactive technology based on VRML and JavaScript, which is essential to a web-based simulation system, has been presented in this paper. Secondly, the geometric and kinematic model is created for representing the turn-milling center motion. Then, the key technologies for machining simulation including material removal, NC codes compiling and collision detection are studied. Finally, to validate feasibility of the proposed system, the virtual machining process for a stepped shaft in the machine tool is carried out. Since the system realizes multiple dynamic demonstrations of virtual machine tool, users can comprehensively understand the product performance. The research for the web-based virtual system of turn-milling center has important research value and application prospect.     

面向印刷机械的虚拟装配系统研究与开发

分析了虚拟装配系统的功能结构，建立了基于配合特征的集成装配模型，采用几何推理和装配知识相结合的方法进行装配序列规划，实现了三维环境下的交互式装配工艺规划与仿真。最后，给出了该系统在某输纸机构装配中的应用实例。     

基于VRML的交互式虚拟装配仿真应用

针对目前CAD软件只生成静态的三维装配体VRML文件的问题,分析了交互式虚拟装配VRML文件的事件流程。虚拟装配中的动态交互性行为使用VRML2.0结合JavaScript进行编程,将机械零部件的动态装配过程以基于VRML的虚拟现实技术来表现出来。     

Virtual human modeling for interactive assembly and disassembly operation in virtual reality environment

Real operators are the initiators in assembly and disassembly activities. They participate throughout the whole process. In this sense, as an avatar of a real operator, virtual human (VH) plays an important role in virtual assembly and maintenance simulations. After detailed analysis of interactive assembly and disassembly process, the function requirements for VH are defined. Based on the defined requirements, the following works are done. First, a real-time driving model is established with a dynamic constraint applied to support personalized human model driving. Then, a driving error model is proposed for quantitatively analysis of VH’s driving error coming from the motion capture system. After that, on the basis of constraint processing method, an interactive operation modeling method for VH is presented. This method deals with interactive operation modeling in scenarios where VH manipulates the product directly, VH manipulates tools, and VH manipulates the product using tools. Finally, an assembly simulation for automobile engine connecting rod caps is implemented and a user survey is carried out. The survey result demonstrates the feasibility and validity of the proposed model and method.