基于数字孪生机房的三维可视化监控系统的设计与实现

针对当前机房的监控管理方式单一、实时性差、透明度低等问题,构建了一种基于数字孪生机房的三维可视化监控系统。以数字孪生的五维模型为指导,构建机房虚拟场景,实现机房三维可视化。论文采用Three.js三维引擎搭建机房三维场景,使用JavaScript语言实现各模块间的功能交互,运用深度学习算法完成机房故障诊断的功能。实验证明:基于数字孪生的机房三维可视化监控系统可以实时监测系统状态,动态展示设备信息,提高了管理效率。     

航空发动机教学实验系统的虚拟装配技术研究

航空发动机虚拟教学实验系统的建设是将VR(Virtual Reality)技术与实验相结合的一次综合性的实验探索与尝试.该系统是将虚拟装配及拆卸、模化实验、模型流场的动态显示及发动机试车等综合仿真实验系统,重点论述了教学实验系统开发中的虚拟装配技术,在对虚拟装配的研究现状分析和总结的基础上,对航空发动机虚拟装配的关键技术和虚拟装配系统的实现方法进行了分析和研究,包括基于数据手套的虚拟手操作、实时碰撞检测、装配路径和装配顺序规划等问题.最后还展示了利用航空发动机三维可视化虚拟装配系统完成虚拟装配操作的实例,并分析了虚拟装配系统与传统装配相比较的优势和特点.     

三维虚拟动态测量系统构建方法研究

针对传统二维测量系统存在测量精度较低、稳定性差的不足,提出一种基于数据交互的三维虚拟动态测量方法;该方法采用三维构型与总线技术同步耦合的工作方式,对三维测量系统中模型驱动的关键问题进行了研究,探讨了三维测量系统中数据交互解决方法的可行性,并将该方法应用于煤矿排水系统,完成了三维虚拟动态测量系统的开发;试验结果表明由该方法实现的三维虚拟动态测量系统具有运行稳定、操作简单、直观性强、可靠性高的优点,应用前景广阔。     

汽车装配线的可视化仿真研究

由于装配系统仿真对象复杂以及传统仿真方法难以建立装配系统的仿真模型,因此该文提出运用面向对象的理论建立汽车装配线的可视化虚拟仿真系统.文中详细论述了实现该仿真系统的关键技术和流程,接着根据离散事件系统的特点介绍了装配仿真系统的仿真策略,最后以某汽车总装车间为例建立了装配线的可视化虚拟仿真系统.通过可视化仿真实现了车间的布局设计和生产过程的动态仿真,并依据仿真结果确定生产线的技术参数以决策生产.     

基于客户定制的产品配置

为了给客户提供一个直观和可视化的产品配置工具,研究了基于客户定制的产品配置模型,包括产品族功能模型、产品族装配模型以及产品配置知识的表达模型.利用该模型构建了一种面向客户基于Web的虚拟产品定制和展示环境,使得用户在该环境下可以提交需求目标,系统根据用户的需求进行配置,生成的产品三维实体模型可在浏览器中动态地观察和操作.     

基于虚拟现实的潜艇虚拟装配系统

该系统是基于虚拟现实技术的潜艇虚拟装配系统。系统使用Creator／Vega虚拟现实软件平台实现,建立非常真实的虚拟装配环境,使用户有身临装配现场的感觉。用户在三维鼠标、位置跟踪器的帮助下可以随意地平移和旋转模型,完成装配操作。同时,该系统运用了Vega容体碰撞检测技术,较好地解决了虚拟装配中的瓶颈--实时碰撞检测。此系统大大缩短了设计周期,节省了设计制造的费用。     

基于开源场景图形的三维可视化与信息管理系统设计

对于产品虚拟装配的三维呈现过程中难以实现零件信息管理问题,结合电动车模型的拆装,提出三维可视化与信息管理技术融为一体的设计方案。首先,建立三维模型库,并根据电动车模型的拓扑结构和辅助信息,如零件的材质、型号等,建立信息库;其次,读取信息库中零件与子装配体间的父子关系信息建立目录树,根据子装配体与场景树均为“多叉树”组成结构的原理进行子装配体的三维呈现,再对子装配体的各个节点设置动画完成拆装呈现;最后,采用多线程方法将电动车配件信息管理与可视化有机结合,实现支持三维的拾取交互查询和检索定位查询等功能。系统以世纪鸟电动车进行验证,实现了三维可视化技术与信息系统相融合,能快速有效地为电动车的三维呈现和虚拟装配提供技术支持。实例验证表明,所设计系统可以有效地将零件的信息管理融入到虚拟装配的三维可视化中。     

VRML 虚拟现实网络互动仿真装配平台的研究

在计算机上实现了虚拟装配的流程以及运用VRML 创建可视化的三维虚 拟场景,提出了一种基于VRML 和Java 的虚拟现实构建方法,以增强VRML 虚拟场景与外 界的交互性,并通过实例提出了创建网络虚拟装配交互仿真的具体方案。该方法不仅可用于 演示网络环境下的可视化装配,也适用于基于VRML 的其它领域科学可视化。     

基于VB和VRML的虚拟仿真实验系统

结合现有的工作描述了虚拟仿真实验系统（VSLS）,阐述了该系统的功能特点和结构模式,对实现该系统的关键技术进行了分析和总结,包括三维场景建模方法、VRML访问实时数据库以及交互式虚拟场景的开发,提出了利用可视化编程语言VB开发一个实现复杂交互动作功能的平台,完成静态VRML文件到动态交互式虚拟文件的转换,重点解决了三维场景模型建立及几何变换、数据库设计及性能优化、三维虚拟实验场景动态组合、虚拟实验场景访问数据库和虚拟实验场景交互性实现等关键技术。     

基于DXF的露天矿二维与三维数据处理及应用

分析基于DXF文件的露天矿地形图数据信息,提取矿区地形图二维与三维数据,利用Open Inventor库函数,进行DXF文件图元的重绘制。完成露天矿DXF文件数据接口设计,实现对矿山生产全方位、多视角、实时动态观察与分析。在AutoCAD软件与露天矿卡车计算机调度系统之间建立数据通道。通过矿区DXF文件中三维数据的提取和预处理,应用Open Inventor三维图形显示系统完成露天矿三维模型渲染和显示。该方法已成功应用于露天矿生产动态可视化监控系统中。     

基于VRML-JAVA的虚拟现实及其协同环境的开发

虚拟现实技术对于制造业信息化有着重要意义。为建立开放技术标准之上的可视化装配系统,该文对基于VRML-JAVA的虚拟现实技术在工程设计领域的应用进行了研究,提出一种新型的Web环境下3D交互仿真结构,复杂的运算和仿真在服务器上进行,从而实现服务器端装配模型和客户端显示模型的分离。并在此基础之上提出协同环境开发的系统结构。该模型不仅可用于网络环境下的可视化装配,也适合于其他领域基于Web的科学可视化。     

Performance analysis of assembly systems with highlift stations: a practical approach

One common problem associated with automatic assembly systems is that some assembly operations may have relatively long cycle times. As a consequence, the productivity, as determined by the operations with the longest cycle time, can be significantly reduced. Therefore, a special form of parallel workstation known as a highlift station was developed to improve the performance of an automatic assembly system. In this paper, we present a simple analytical model that can help engineers to estimate the performance of highlift stations. This model is particularly useful at the design stage, as only approximate results are necessary for selecting the configuration.     

Direct 3D Manipulation Techniques for Interactive Constraint-based Solid Modelling

This paper presents a novel constraint-based 3D manipulation approach to interactive constraint-based solid modelling. This approach employs a constraint recognition process to automatically recognise assembly relationships and geometric constraints between entities from 3D manipulation. A technique referred to as allowable motion is used to achieve accurate 3D positioning of a solid model by automatically constraining its 3D manipulation without menu interaction. A set of virtual design tools, which can be used to construct constraint-based solid models within a virtual environment, are also supported. These tools have been implemented as functional 3D objects associated with several pre-defined modelling functions to simulate physical tools such as a drilling tool and T-square. They can be directly manipulated by the user, and precisely positioned relative to other solid models through the constraint-based 3D manipulation approach. Their modelling functions can be automatically triggered, depending upon their associated constraints and the user's manipulation manner. A prototype system has been implemented to demonstrate the feasibility of these techniques for model construction and assembly operations.     

三维虚拟物体表面重建的研究

在激光扫描共焦显微三维成像，CT成像，MRI成像，以及在图象处理和识别中，三维物体的显示是必不可少的，目前，最流行的显示方式是虚拟物体的三维重建，通常虚拟物体三维重中以采用体素级重建，可也以采用切片极重建，由于切片级重建仍需要解决物体轮廓对应，分叉曲面，轮廓拼接等关键性问题，为此，提出了一些新的方法，在这些方法中，轮廓的对应采用OR运算和AND运算来确定，如果两个轮廓的OR和ND运算结果满足预先设置的准则，则这两个轮廓相对应；分叉曲面采用数字形态学方法来分解，其由形态学方法生成的边界就是分叉曲面的分割线，轮廓拼拦则是将对应轮廓经多边形简化后，由三角形接拼法来构成表面，且三角形是根据最小轮廓跨接边准则来构建的，通过对这些方法进行的实验结果表明，理论与实际完全相符，这些方法的优点是编程简单，运算速度快。     

Assembly simulations in virtual environments with optimized haptic path and sequence

Virtual assembly and disassembly simulations can be accomplished in intuitive and effective ways using haptic information in virtual environments (VEs). Potential problems in a given assembly scheme can be predicted by a user who may be able to suggest an alternative scheme in the VE. This paper describes an intelligent virtual assembly system in which an optimal assembly algorithm is used to allow haptic interactions during virtual assembly operations. This algorithm provides optimal paths for haptic guidance as well as an assembly sequence of the parts to be assembled. The performance of the given assembly schemes was simulated using a virtual assembly system. Experimental results showed that the haptic-path sequence-guidance (HSG) mode gave the best performance improvement in terms of accumulated assembly time (28.33%) and travel distance (15.05%) compared to the unguided mode, while the sequence-guidance (SG) mode alone increased performance by 15.33% for assembly time and 11.36% for travel distance. The experimental results were analyzed by the sub-tasks of gripper selection, inter-part movement, and part assembly. For the HSG mode, the greatest contributor to the time and distance reductions was the optimized haptic path, while for the SG mode, the reduced numbers of gripper exchanges and orientation change made the greatest contributions to reducing the assembly time and the travel distance. As a result, the optimized haptic path, as well as sequence guidance, enhanced the working performance of virtual assembly tasks.     

结合三维视景的自定义位图动画实现

作为激光传输系统的关键环节,激光传输的建模和仿真具有重要意义.提出了一种利用三维视景的自定义位图动画实现激光传输仿真的新方法,该方法首先通过调用动态链接库将三维虚拟仿真与传统的二维数值模拟相结合,然后利用鼠标或键盘对虚拟场景中观测点位置或三维模型进行平移或旋转操作实现模型拾取,科技人员可以在看得见,摸得着的情况下修改模型的各个参数,并可以实时或离线显示计算仿真结果.该方法为科技人员提供了良好的人机交互界面,仿真结果也表明了该方法可操作性和有效性.     

Towards the development of a virtual environment-based training system for mechanical assembly operations

In this paper, we discuss the development of Virtual Training Studio (VTS), a virtual environment-based training system that allows training supervisors to create training instructions and allows trainees to learn assembly operations in a virtual environment. Our system is mainly focused on the cognitive side of training so that trainees can learn to recognize parts, remember assembly sequences, and correctly orient the parts during assembly operations. Our system enables users to train using the following three training modes: (1) Interactive Simulation, (2) 3D Animation, and (3) Video. Implementing these training modes required us to develop several new system features. This paper presents an overview of the VTS system and describes a few main features of the system. We also report user test results that show how people train using our system. The user test results indicate that the system is able to support a wide variety of training preferences and works well to support training for assembly operations.

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A desktop virtual reality-based interactive modular fixture configuration design system

Modular fixture configuration design is a complicated task requiring strong professional background and practical experience. However, automated or semi-automated computer aided modular fixture systems based on CAD packages still are not well accepted by the manufacturing industry due to the lack of intuitive interaction and immediate feedback compared with traditional models such as paper and physical models. In this paper, a novel Virtual Reality-based system for interactive modular fixture configuration design is presented. We use a multi-view based modular fixture assembly model to assist information representation and management. In addition, the suggested strategy is compatible with the principles of virtual environment and it is easy to reutilize the element model. Based on geometric constraints, we propose a precise 3D manipulation approach to improve intuitive interaction and accurate 3D positioning of fixture components in virtual space. Thus, the modular fixture configuration design task can precisely be performed in virtual space.