基于SketchUp和VRML的虚拟漫游系统开发

虚拟现实应用越来越广泛。VRML是用于描述交互式三维空间的虚拟现实建模语言。该文提出了一种基于SketchUp和VRML技术虚拟漫游系统的开发方法,即用SketchUp构建三维模型,用VRML语言实现场景漫游的交互控制,从而设计与实现一个三维虚拟漫游系统。     

基于Quest3D的虚拟中药药材展示系统研究与实现

随着计算机软硬件和虚拟现实技术的发展,运用虚拟现实技术辅助规划设计和展示已成为该领域的研究热点.本文介绍了一种基于虚拟现实软件实现的虚拟药材展示系统的设计方法,即利用三维建模软件3ds max进行三维实体及场景建模,采用虚拟交互平台Quest3D为场景驱动.本文以应用该方案实现的虚拟药材展示系统为例,重点介绍了系统架构和实现的技术流程,并对实现过程中的场景建模技术、交互设计中的图形化设计方法以及增强场景真实感方法做了深入的阐述.     

基于虚拟现实的汽车平顺性仿真试验系统设计

本文将虚拟现实技术应用于汽车平顺性仿真试验技术中。对汽车平顺性虚拟试验场景进行了层次化虚拟场景结构设计和汽车平顺性虚拟试验系统对象类设计。研究了汽车平顺性虚拟试验环境建模和交互、双目立体视觉实现等问题。开发了面向视景仿真的汽车平顺性虚拟试验的桌面VR原型系统,划分了系统层次结构,介绍了系统的软硬件基本配置,设计了系统用户操作界面,实现了汽车平顺性虚拟试验要求。     

露天矿生态重建VR仿真系统研究

介绍了用虚拟现实技术开发露天矿生态重建视景仿真系统的几项关键技术。针对露天矿生态重建应用特点,采用层次型与面向对象相结合的三维数据结构,构造露天矿生态重建视景仿真模型;用LOD技术为露天矿虚拟环境中的地形和建筑物构造多层次、多分辨率的细节模型,提出了基于视点的连续LOD算法,对三维地形模型按数据块进行简化,以适应不同硬件平台和视觉特性的分辨率需求;采用Vega软件实现露天矿三维动态全景图显示与实时驱动的基本方法;用实物标图技术在虚拟场景中进行生态重建规划方案的设计方法;提出一种新的用鼠标获取三维虚拟场景中实体模型信息的算法,实现三维动态查询和与外部数据库的链接。     

探究立体显示系统在虚拟现实中的运用

论述主、被动立体显示的基本原理,提出虚拟现实中的交互式立体显示系统的架构设计和运用方法.重点阐述基于PC机与专业双屏显卡阵列的大场景立体显示系统的构成要素及原理,并指出与之对应的虚拟场景生成方法,为交互式仿真系统中实现立体显示特别是沙盘立体显示系统给出了解决方案,最后分析比较大场景主、被动立体显示方式优劣及未来发展趋势.     

基于虚拟现实技术的油田仿真培训系统的设计

油田作业培训的安全问题一直备受关注,为了保证油田作业培训的安全性,将虚拟现实技术应用于油田仿真培训工作,建立油田仿真培训系统.该系统基于虚拟现实技术,设计了油田仿真培训系统的总体结构,提出了演示、操作演练和考评三种培训模式,阐述了交互式菜单和对三维实体的交互式操作两种人机交互方式,引入了虚拟人和虚拟手的模型及控制技术.该系统虚拟场景逼真,培训功能齐全,用户可以进行多视点、多场景的浏览,让用户有身临其境的感觉,目前已经应用到实际培训中,效果良好.     

基于虚拟现实的煤矿大型设备培训系统研究

针对煤矿设备操作培训中存在的不足,设计并实现了一种基于虚拟现实技术的煤矿大型设备虚拟培训系统,利用三维建模软件Maya对井下主要设备采煤机、液压支架、刮板输送机等生产机械设备进行三维模型的创建,结合虚拟现实制作软件Unity3D进行虚拟场景整合与交互设计,利用C#编程语言实现对煤矿大型设备运动仿真控制.通过接口电路实现用户与虚拟场景设备的真实交互.经测试表明,系统不仅实现了煤矿大型设备操作培训的功能,而且增加了系统的交互性,弥补了传统培训方式的不足,节约了培训成本,缩短了培训周期.     

虚拟现实建立动态场景的研究

随着虚拟现实技术的发展,对虚拟现实场景不仅要求有逼真的效果,同时还要求有生动的交互功能,而VRML(Vitual Reality Modeling Language)与Java的结合是目前常用的交互式虚拟现实技术。文章系统介绍了虚拟现实建模语言VRML,采用JAVA做为脚本建立动态场景的原因并具体介绍了VRML与Java结合建立动态交互场景的两种方式,以及JSAI和EAI的区别。     

虚拟现实建立动态场景的研究

随着虚拟现实技术的发展，对虚拟现实场景不仅要求有逼真的效果，同时还要求有生动的交互功能，而VRML（Vitual Reality Modeling Language）与Java的结合是目前常用的交互式虚拟现实技术。文章系统介绍了虚拟现实建模语言VRML，采用JAVA做为脚本建立动态场景的原因并具体介绍了VRML与Java结合建立动态交互场景的两种方式，以及JSAI和EAI的区别。     

基于Arduino的虚拟现实交互系统实验案例设计

综合运用嵌入式、三维建模、虚拟现实等技术,提出一个软硬件结合的虚拟现实交互系统典型案例,实现虚拟场景与现实环境的实时交互控制。通过3DMAX和Unity3D软件设计虚拟现实交互场景,采用Arduino核心板搭建场景的控制模块,运用光敏电阻和湿度传感器实时获取环境信息并注入虚拟场景中,实现虚拟现实交互系统。     

Quality assessment for virtual reality technology based on real scene

Virtual reality technology is a new display technology, which provides users with real viewing experience. As known, most of the virtual reality display through stereoscopic images. However, image quality will be influenced by the collection, storage and transmission process. If the stereoscopic image quality in the virtual reality technology is seriously damaged, the user will feel uncomfortable, and this can even cause healthy problems. In this paper, we establish a set of accurate and effective evaluations for the virtual reality. In the preprocessing, we segment the original reference and distorted image into binocular regions and monocular regions. Then, the Information-weighted SSIM (IW-SSIM) or Information-weighted PSNR (IW-PSNR) values over the monocular regions are applied to obtain the IW-score. At the same time, the Stereo-weighted-SSIM (SW-SSIM) or Stereo-weighted-PSNR (SW-PSNR) can be used to calculate the SW-score. Finally, we pool the stereoscopic images score by combing the IW-score and SW-score. Experiments show that our method is very consistent with human subjective judgment standard in the evaluation of virtual reality technology.

     

Reduced mental load in learning a motor visual task with virtual 3D method

Distance learning is expanding rapidly, fueled by the novel technologies for shared recorded teaching sessions on the Web. Here, we ask whether 3D stereoscopic (3DS) virtual learning environment teaching sessions are more compelling than typical two‐dimensional (2D) video sessions and whether this type of teaching results in superior learning. The research goal was to compare learning in 2 virtual learning scenarios—on 2D displays and with an identical 3DS scenario. Participants watched a 2D or 3DS video of an instructor demonstrating a box origami paper‐folding task. We compared participants' folding test scores and self‐assessment questionnaires of the teaching scenarios and calculated their cognitive load index (CLI) based on electroencephalogram measurements during the observation periods. Results showed a highly significant difference between participants' folding test scores, CLI, and self‐assessment questionnaire results in 2D compared to 3DS sessions. Our findings indicate that employing stereoscopic 3D technology over 2D displays in the design of emerging virtual and augmented reality applications in distance learning has advantages.     

基于OGRE的双目立体显示研究与实现

双目立体显示是计算机图形学中的一项前沿技术,在虚拟现实领域发挥着重要作用.分析了双目立体显示的原理,根据平行双目投影模型,提出一种基于OGRE(面向对象图形渲染引擎)的双目立体显示方案.该方案充分利用OGRE中的虚拟摄像机和视口合成技术,并在底层结合CG脚本,保证了渲染的效率.结果表明,对于正负两种视差,该方案均有明显的立体效果,并能灵活漫游及更换不同的场景,非常适合实际应用.     

虚拟现实场景中立体视差生成算法的研究

近几年来,虚拟现实技术的广泛应用前景引起了国内外越来越多学者的兴趣和重视,而且国外的一些机构在这方面的研究也已经取得了一些很重要的成果。立体显示技术是虚拟现实的关键技术之一,而对视差的研究又是立体显示技术一个很重要的方面。该文首先论述了双眼的生理结构和双眼视差的形成以及计算机上实现立体视觉的原理,然后对虚拟现实中生成双眼视差得到立体图对的多种方法进行了研究,并在虚拟现实设备上实现,通过比较和分析各种显示效果给出了研究结论。     

Virtual view synthesis of people from multiple view video sequences

This paper addresses the synthesis of novel views of people from multiple view video. We consider the target area of the multiple camera 3D Virtual Studio for broadcast production with the requirement for free-viewpoint video synthesis for a virtual camera with the same quality as captured video. A framework is introduced for view-dependent optimisation of reconstructed surface shape to align multiple captured images with sub-pixel accuracy for rendering novel views. View-dependent shape optimisation combines multiple view stereo and silhouette constraints to robustly estimate correspondence between images in the presence of visual ambiguities such as uniform surface regions, self-occlusion, and camera calibration error. Free-viewpoint rendering of video sequences of people achieves a visual quality comparable to the captured video images. Experimental evaluation demonstrates that this approach overcomes limitations of previous stereo- and silhouette-based approaches to rendering novel views of moving people.     

Binocular mobile augmented reality based on stereo camera tracking

Mobile augmented reality (AR) applications have become feasible with the evolution of mobile hardware. For example, the advent of the smartphone allowed implementing real-time mobile AR, which triggered the release of various applications. Recently, rapid development of display technology, especially for stereoscopic displays, has encouraged researches to implement more immersive and realistic AR. In this paper, we present a framework of binocular augmented reality based on stereo camera tracking. Our framework was implemented on a smartphone and supports autostereoscopic display and video see-through display in which a smartphone can be docked. We modified edge-based 3-D object tracking in order to estimate poses of left and right cameras jointly; this guarantees consistent registration across left and right views. Then, virtual contents were overlaid onto camera images using estimated poses, and the augmented stereo images were distorted to be shown through a video see-through display. The feasibility of the proposed framework is shown by experiments and demonstrations.     

Free-viewpoint video relighting from multi-view sequence under general illumination

We proposed an approach to create plausible free-viewpoint relighting video using multi-view cameras array under general illumination. Given the multi-view video dataset recorded using a set of industrial cameras under general uncontrolled and unknown illumination, we first reconstruct 3D model of the captured target using existing multi-view stereo approach. Using the coarse geometry reconstruction, we estimate the spatially varying surface reflectance in the spherical harmonics domain considering the spatial and temporal coherence. With the estimated geometry and reflectance, the 3D target is relit to the novel illumination with the environment map of the target environment. Relit performance is enhanced using a flow- and quotient-based transfer strategy to achieve detailed and plausible performance relighting. Finally, the free-viewpoint video is generated using a view-dependent rendering strategy. Experimental results on various dataset show that our approach enables plausible free-view relighting, and opens up a path towards relightable free-viewpoint video using less complex acquisition setups.     

基于虚拟现实的塑料注塑成型系统场景可视化

虚拟现实,作为一门新型技术,已成功地应用于工程、设计和制造业领域.该文针对塑料注塑成型复杂的设计、制造、加工过程,将虚拟现实技术应用到塑料注塑成型过程中,并利用Delaunay三角剖分技术结合立体显示技术,开发了一种实用的虚拟场景.在此场景中可实现注射系统的全部设计和制造过程,并结合面向对象的编程技术和OpenGL图形库,实现注射成型系统在虚拟现实场景中的动态可视化,从而能够预先感知注射系统在设计、制造过程中可能出现的问题,并加以解决,实践证明了其可行性.     

Applications of the Responsive Workbench

Many interface devices for virtual reality provide full immersion inside the virtual environment. This is appropriate for numerous applications that emphasize navigating through a virtual space. However, a large class of problems exists for which navigation is not the critical issue. Rather, these applications demand a fine-granularity visualization and interaction with virtual objects and scenes. This applies to a host of other applications typically performed on a desktop, table or workbench. Responsive Workbench technology offers a new way to develop virtual environments for this rather sizable class of applications. The Responsive Workbench operates by projecting a computer-generated, stereoscopic image off a mirror and through a table surface. Using stereoscopic shuttered glasses, users observe a 3D image displayed above the tabletop. By tracking the group leader's head and hand movements, the Responsive Workbench permits changing the view angle and interacting with the 3D scene. Other group members observe the scene as the group leader manipulates it, facilitating communication among observers. Typical methods for interacting with virtual objects on the workbench include speech recognition, gesture recognition and a simulated laser pointer (stylus). This article features Responsive Workbench applications from four institutions that have pioneered this technology. The four applications are: visualization, situational awareness, collaborative production modeling and planning, and a virtual windtunnel     

The Nintendo Wii as a tool for neurocognitive rehabilitation,training and health promotion

Health professionals have used virtual reality as an aid for several types of treatment. Given that virtual reality systems are expensive and not always available, a more accessible type of virtual reality technology is video games. The Nintendo Wii™ (NW) is a video game system that uses virtual reality technology, as defined by Deutsch, Borbely, Filler, Huhn, and Guarrera-Bowlby (2008), which may be used for health promotion. The Nintendo Wii™ also provides an opportunity for social interaction; thus, it is a promising tool with great potential for the treatment of specific disorders.The aim of this article is to evaluate the ways in which the Nintendo Wii has been used to treat specific disorders or to promote cognitive or physical improvements through a review of the literature. The results have shown that the NW is a potentially useful tool in some therapeutic treatments that can be used with people of diverse social statuses and tastes. Despite the positive initial results, further studies are required to provide a better evaluation of video game usage in therapeutic programs.