Teaching your system to share

Creating multi-user virtual worlds is a relatively new challenge for developers of virtual reality applications. It is especially challenging to build networked VR systems based on inexpensive PC-based hardware, due to limitations in system software and inefficient networking hardware. This article explains how we created a multi-person shared virtual environment using DOS-based PCs. It also covers some of the design goals in creating a collaborative design tool for creating and modifying virtual buildings. Workroom is a general purpose simulation infrastructure that allows multiple participants to interact in unpredictable ways while minimizing simulation latency     

Using virtual reality technology for aircraft visual inspection training: presence and comparison studies

The aircraft maintenance industry is a complex system consisting of several interrelated human and machine components. Recognizing this, the Federal Aviation Administration (FAA) has pursued human factors related research. In the maintenance arena the research has focused on the aircraft inspection process and the aircraft inspector. Training has been identified as the primary intervention strategy to improve the quality and reliability of aircraft inspection. If training is to be successful, it is critical that we provide aircraft inspectors with appropriate training tools and environment. In response to this need, the paper outlines the development of a virtual reality (VR) system for aircraft inspection training.

VR has generated much excitement but little formal proof that it is useful. However, since VR interfaces are difficult and expensive to build, the computer graphics community needs to be able to predict which applications will benefit from VR. To address this important issue, this research measured the degree of immersion and presence felt by subjects in a virtual environment simulator. Specifically, it conducted two controlled studies using the VR system developed for visual inspection task of an aft-cargo bay at the VR Lab of Clemson University. Beyond assembling the visual inspection virtual environment, a significant goal of this project was to explore subjective presence as it affects task performance. The results of this study indicated that the system scored high on the issues related to the degree of presence felt by the subjects. As a next logical step, this study, then, compared VR to an existing PC-based aircraft inspection simulator. The results showed that the VR system was better and preferred over the PC-based training tool.     

PC-based off-line programming in the shipbuilding industry: open architecture

In this paper, a PC-based off-line programming (OLP) method using the virtual reality modeling language is proposed. The developed OLP system consists of simulation programs, a block-arrangement algorithm, an optimal traveling-path generation algorithm, an automatic robot program generator and the TRIBON CAD interface. The strength of the developed PC-based OLP system lies in its flexibility in handling the changes in the robot's target objects. The operator can generate robot programs very easily and quickly. Possible applications of the developed OLP can be extended to port automation, container loading/unloading processes as well as painting and grinding processes in the shipbuilding industry.     

Developing microcomputer software for CAD and CAM education

Many educators find that CAD and CAM laboratories and software which are necessary for their programs are prohibitively expensive to install and maintain. With the advent of powerful yet inexpensive microcomputing equipment, educational institutions now have an excellent opportunity to instruct NC, CAD and CAM technologies using personal computers (PCs). In this paper, several PC-based software programs developed for educational use are presented.     

基于虚拟现实技术的车床仿真系统

基于开发CA6132型车床虚拟教学软件的目的,采用了虚拟仿真的方法,开发了带有虚拟现实特征的车床教学系统软件.提出了虚拟车床开发的一般流程,阐述了矫正图像的立面分割技术,开发了基于Unity3D引擎软件的虚拟车床仿真系统,解释了虚拟现实的基本原理,建立了CA6132型车床的三维模型,提出了在Unity3D下车床加工的仿真方法,开发了基于虚拟现实设备zSpace虚拟现实车床仿真系统,提出了虚拟现实的场景交互方式,降低了实际车床操作的危险.     

虚拟现实软件系统开发方法研究

虚拟现实技术是一门综合性技术,涉及计算机图形学、多媒体技术、人机交互和人工智能等多个领域,在教育、医疗、娱乐、军事等众多领域有非常广泛的应用。所有这些技术和应用最终都要靠计算机软件来实现,这就使得虚拟现实系统的软件变得十分庞大和复杂,涉及许多多媒体数据。传统软件开发方法和程序设计技术侧重于处理文本数据,显然不能满足开发虚拟现实软件的需要。试图以所在团队研发成功的PAR方法和PAR平台为基础,根据虚拟现实软件系统的特征,探寻虚拟现实软件系统开发的新方法,进一步扩充和完善PAR平台中已有多媒体处理技术、形式化建模技术和C#等高级语言程序自动生成系统。     

A Sensorized Garment Controlled Virtual Robotic Wheelchair

This paper presents the design and performance of a body-machine-interface (BoMI) system, where a user controls a robotic 3D virtual wheelchair with the signals derived from his/her shoulder and elbow movements. BoMI promotes the perspective that system users should no longer be operators of the engineering design but should be an embedded part of the functional design. This BoMI system has real-time controllability of robotic devices based on user-specific dynamic body response signatures in high-density 52-channel sensor shirt. The BoMI system not only gives access to the user’s body signals, but also translates these signals from user’s body to the virtual reality device-control space. We have explored the efficiency of this BoMI system in a semi-cylinderic 3D virtual reality system. Experimental studies are conducted to demonstrate, how this transformation of human body signals of multiple degrees of freedom, controls a robotic wheelchair navigation task in a 3D virtual reality environment. We have also presented how machine learning can enhance the interface to adapt towards the degree of freedoms of human body by correcting the errors performed by the user.     

一个基于局域网的微机虚拟漫游演示系统

介绍了一个基于局域网的微机虚拟漫游演示系统的基本组成和软件开发要点。系统采用头盔显示器和位置跟踪器作为与虚拟环境进行交互的设备,自行研制开发了场景编辑器、场景漫游器、位置跟踪等全部应用软件,使参与者能以接近自然的方式在虚拟场景中漫游。     

Computer-aided software engineering and Ada -- The technological marriage of the decade

Computer-Aided Software Engineering (CASE) tools and Ada language compilers are now available for both mainframes and Personal Computers (PCs). Although CASE methodologies have existed since the early 1970s and the use of Ada has been required by the Department of Defense since 1985, only recently have CASE and Ada become of serious interest to engineers.

This paper identifies the capabilities of PC-based CASE software, the reasons for combining CASE with Ada, and the impact of CASE and Ada on research and teaching in the areas of Industrial and Computer Engineering. Based on the authors' first-hand experience, the advantages and/or disadvantages of several CASE tools and Ada environments will be discussed. Other topics addressed include the meanings of related terminology (e.g., object-oriented programming, design methodologies) and the future ramifications of CASE and Ada on the software engineering community.     

基于PC的多通道超高速数据采集系统的设计与实现

论述了一种基于ＩＢＭ－ＰＣ机的超高速实时数字存储示波系统．采用“闪烁”Ａ／Ｄ转换器，软件虚拟面板，高速图形环境，ＰＣ仪器设计等先进技术和思想，开发出了４通道３２ＭＳａ／ｓ实时数字存储示波系统，并投入批量生产。提出了采用“闪烁”Ａｐｅ超高速数据采集和分时分片多体缓冲存储技术的设计方案，文中介绍了系统硬软件结构和主要硬件单元电路的实现，并简要说明了系统抗于扰措施。     

基于软件的无线网绿色代理系统

提出了一种基于软件架构的无线网绿色节能代理系统.针对无线网络的特点,通过在代理服务端创建网内其他终端的虚拟网卡和虚拟镜像,配合针对终端移动的代理服务器切换机制与重发机制,使得无线终端在节能时快速进入休眠状态,在响应请求时快速、有效地被唤醒.该软件系统不对原有网络拓扑或硬件系统做任何改变,所以具有普适性和可移植性强的特点.该系统被实际部署到一个包括11台有线与无线上网的计算机测试平台上通过长时间的监测,整个网络功耗节省了超过60％,充分说明了该系统在实际应用中的经济价值.     

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。     

采煤机虚拟现实装配仿真系统研究

针对煤矿装备虚拟装配应用问题,基于Visual Studio 2010、OSG、Cegui、VC++等 软件平台和相关硬件设备,搭建了功能完整、使用方便、交互性好、沉浸感强的某型号电牵引采 煤机虚拟现实装配应用系统,详细描述了系统的功能结构、技术方案与构建方法;针对构建方法 中的模型制作技术,结合UG 与3DsMax 的建模优势,提出先在UG 中建立CAD 精确模型,后 利用3DsMax 对模型进行转换、修改、优化和渲染,最终生成高质量虚拟现实模型的模型处理方 法,弥补了艺术类模型装配精度较低和工程CAD 模型很难直接生成虚拟现实模型的不足。     

基于光学映射虚物体的并行绘制

尽管当前基于全局光照模型的图形绘制方法可以渲染出高质量的图象 ,但因为其计算量巨大 ,难以适用于诸如建筑物漫游、虚拟现实等对绘制速度有严格要求的场合 .为此引入光学映射虚物体的概念 ,利用构建在联网PC机上的集群系统 ,并行创建反射和折射虚物体 ,然后利用集群中各节点的图形加速硬件 ,像处理实际三维物体一样绘制这些虚物体 ,可以快速地绘制出反射 /折射效果的图象 .实验结果证明 ,该方法利用 CU P的计算能力和图形硬件的加速特性实现了真实感图形的高性能绘制 ,特别适用于诸如建筑物漫游、计算机动画和虚拟现实等要求交互式绘制的场合     

WAVE: Sound and music in an immersive environment

This paper presents WAVE—a Virtual Audio Environment, which embraces the implementation of an immersive musical instrument model that uses three-dimensional (3D) sound techniques combined with visualisation and virtual reality technologies. This prototype environment aims to extend the idea of a musical instrument into a new musical/audio system, incorporating traditional musical concepts side by side with actual music concepts, in order to progress one step further in the music/sound composing and performing approaches.

The architecture of the system is based on low-cost hardware and open source software with affordable professional audio equipment to maintain an adequate sound quality. Also several applications of this virtual environment are discussed in the paper, including the way to satisfy at the same time composers, performers, music/audio students or even simple occasional users.     

Adapting Virtual Reality for the Participatory Design of Work Environments

This paper describes the evolution of a standard PC-based virtual reality tool which has been adapted for the participatory design of work environments. Tool features, method of control and combination with other participatory design tools are investigated in the context of a particular design situation. This research is aimed at participatory design facilitators to aid in the adaptation of similar virtual reality systems for a similar purpose. The context of this work is the Envisionment Workshop, in which a group of workers participate with design experts in using full-scale modelling, pedagogical drama, and democratic meetings to (re)design their workplace. A series of prototypes have been developed and tested during the design of a new university in the region using a case study methodology to provide high ecological validity. These were preceded by a task analysis, brainstorming and pilot study. The results suggest that such a tool can be constructed and used successfully by a small group of people using projected virtual reality. However larger groups suffer from a bottleneck at the input devices such that a virtual reality expert must take control and build what the participants wish. This revised version was published online in August 2006 with corrections to the Cover Date.     

基于VR技术的虚拟维修仿真系统设计与应用

针对产品并行研发模式下的维修性问题,将虚拟现实技术引入到产品维修仿真中,即在计算机生成的虚拟现实环境中对产品进行维修仿真分析。文中以单通道被动立体投影系统为虚拟现实环境,以DELMIA、VRCO VisTool、CDVI、Pro/E等软件为虚拟现实软件系统,构建了一个虚拟维修系统,阐述了系统中VR外设集成、环境建模与数据转换、碰撞检测、人机工效和立体显示等关键技术。最后以某型雷达天线转台维修为例,验证了虚拟维修的有效性。     

基于游戏引擎的三维虚拟漫游系统实现

三维虚拟环境漫游是虚拟现实技术应用的基本方向之一,具有重要的研究意义与应用价值。基于成熟的游戏引擎技术,提出一个具有较强通用性和可扩展性的三维虚拟漫游系统开发框架,并从3D场景快速构建、3D场景实时绘制、高级视觉特效生成和基于物理的场景模拟等四个方面详细介绍了该框架的关键技术实现。通过对系统原型的测试表明,采用该开发框架所构建的三维虚拟漫游系统可在一般的普通主流PC机上达到较好的性能和表现效果。     

Projective virtual reality as a basis for on‐line control of complex systems‐not only‐over the internet

Already in 1994 the term Projective Virtual Reality was coined and a first implementation was used to control a complex multirobot system in Germany over the Internet from California. Building on this foundation, the general aim of the development of virtual reality technology for automation applications at the Institute of Robotics Research (IRF) today is to provide the framework for Projective Virtual Reality for a broad range of applications. The general idea of Projective Virtual Reality is to allow users to “project” actions carried out in the virtual world into the real world by means of robots or other means of automation. The framework is based on a task‐oriented approach which builds on the “task deduction” capabilities of a newly developed virtual reality system and a task planning component. The advantage of this approach is that robots which work at great distances from the control station can be controlled as easily and intuitively as robots that work right next to the control station. Robot control technology now provides the user in the virtual world with a “prolonged arm” into the physical environment, thus paving the way for intuitive control of complex systems over the Internet—and in general for a new quality of user‐friendly man‐machine interfaces for automation applications. Lately, this work has been enhanced by a new structure that allows one to distribute the virtual reality application over multiple computers on a network. With this new feature, it is now possible for multiple users to share the same virtual room, although they may physically be thousands of miles apart. They only need an Internet connection to share this new experience. Lately, the network distribution techniques have been further developed to not just allow users to cooperate over networked PCs but also to be able to set up a panorama projection or a cave running of a networked cluster of PCs. This approach cuts down the costs for such a high‐end visualization environment drastically and allows for a new range of applications. © 2005 Wiley Periodicals, Inc.     

3DS模型在虚拟现实几何建模中的应用

几何建模是开发虚拟现实系统过程中最基本，最重要的工作之一，该文采用了3DS模型文件作为虚拟环境中几何模型的主要存储格式，并且从理论上、实际应用方法以及试验仿真结果几个方面分析了该方法的可行性，通用性，说明了在要求不高的条件下，采用3DS模型和相关的三维建模软件进行虚拟现实研究工作是一条现实的途径。