城市蒸汽管道数字系统设计方法

本文阐述城市蒸汽管道数字系统框架。引入ISO10303国际标准,采用基于实体对象的分布式CAD系统,并说明如何利用该标准进行建模技术研究,讨论建立城市蒸汽数字管道系统的实现方法。通过产品数据管理系统实现虚拟现实技术融合在城市蒸汽数字管道系统。研究表明,所提出的模型易于反复进行计算机仿真试验,在管道工程实际应用中有重要的价值。     

虚拟现实建模技术在数字化发射场中的应用

建立数字化发射场是卫星发射信息化和应急保障的基础。本文结合某卫星发射场实时性和交互性视景仿真实现的特点,采用基于三维几何模型的建模及动态显示技术的虚拟场景创建方法,讨论了虚拟漫游系统中建模流程、方法,以及关键技术的实现,分析了通用的三维场景建模的技术路线和流程,给出了地物、天空和实体模型构建的实际解决方案、方法,讨论了基于MultiGen Creator的模型格式转换、纹理贴图、模型简化、LOD技术、DOF技术等建模关键技术。采用MultiGen Creator和Vega软件平台,开发出了一个桌面型的虚拟发射场仿真系统,实现了发射场的数字化和卫星发射的实时仿真。     

智能三维虚拟试衣模特仿真系统设计*

针对服装物理仿真通常计算量庞大、在低端硬件平台或交互式环境进行高质量模拟的挑战,将人工生命思想引入服装纹理生成,基于混合虚拟现实技术研究开发了智能三维虚拟试衣模特仿真系统。通过在三维空间中构建与真实人体类似的三维虚拟模特作为消费者的试穿替身,同时设计实现了场景屏风功能,这样不但便于根据着装场合自由切换服装纹理,而且可以让消费者通过这一虚拟平台更为直观、自由地观察着装效果为了使三维试衣系统更为智能化,还建立了服装搭配合适度智能评价系统。     

A multi-regional computation scheme in an AR-assisted in situ CNC simulation environment

Computer numerical control (CNC) simulation systems based on 3D graphics have been well researched and developed for NC tool path verification and optimization. Although widely used in the manufacturing industries, these CNC simulation systems are usually software-centric rather than machine tool-centric. The user has to adjust himself from the 3D graphic environment to the real machining environment. Augmented reality (AR) is a technology that supplements a real world with virtual information, where virtual information is augmented on to real objects. This paper builds on previous works of integrating the AR technology with a CNC machining environment using tracking and registration methodologies, with an emphasis on in situ simulation. Specifically configured for a 3-axis CNC machine, a multi-regional computation scheme is proposed to render a cutting simulation between a real cutter and a virtual workpiece, which can be conducted in situ to provide the machinist with a familiar and comprehensive environment. A hybrid tracking method and an NC code-adaptive cutter registration method are proposed and validated with experimental results. The experiments conducted show that this in situ simulation system can enhance the operator’s understanding and inspection of the machining process as the simulations are performed on real machines. The potential application of the proposed system is in training and machining simulation before performing actual machining operations.     

浅析虚拟现实技术

虚拟现实技术是一门综合性很强的高新技术,该技术被广泛应用于先进制造、军事模拟、数字城市、生物医学等众多领域.本文追溯了虚拟现实技术的起源,探讨了该技术的三大特点:沉浸感、交互性和构想性,并根据沉浸的不同程度将虚拟现实技术分为四大类型:桌面式虚拟现实、沉浸式虚拟现实、增强现实的虚拟现实以及分布式虚拟现实.     

虚拟环境建模及实时性改善方法

提出了虚拟现实软件实现方法的概念,利用交互方式的,比较,阐明了虚拟现实与仿真的区别,通过计算机三维实体造型和真实感环境泻染技术,实现了虚拟环境建模,通过融入增强现实的思想,把握虚实结合尺度,将基于图象的方法与基于建模的相结合,从而改善了眯拟环境下交互的实时性。     

数字孪生与生产线仿真技术研究

随着新一代信息技术与制造技术的深度融合,仿真技术正向着信息系统与物理系统深度融合和高效协同的方向发展,应运而生的数字孪生技术成为近年来的新兴研究热点.为探索采用新一代信息技术促进离散制造行业数字化转型升级,从仿真技术的发展脉络和应用场景入手,引入基于数字孪生技术开展生产线仿真分析的研究,介绍了数字孪生技术的概念和内涵,...     

虚拟切削加工系统的设计与实现

虚拟制造是近年出现的一种先进制造技术,虚拟切削加工在虚拟制造中占有重要地位。为了提供虚拟的加工环境和验证工艺设计的正确性,对切削加工过程的计算机仿真方法进行了研究,以OSG作为图形支持系统,用VC++开发了切削加工仿真系统。该系统实现了对毛坯切割的仿真,可对刀具运动切割情况进行实时监控,较好的再现了加工中毛坯的成型过程。     

虚拟手交互中约束类物体操作研究

虚拟手技术是虚拟现实技术中的一种交互方式，是指通过手势识别技术将人的真实手映射到虚拟环境中并与虚拟物体进行交互操作的人机交互方式。主要应用于虚拟训练、虚拟手术和虚拟装配等领域。对虚拟手交互的约束类对象进行了研究，提出了基于运动学的约束类物体操作方法，解决了阀门类有约束物体交互中虚拟手姿态不真实、操作不可控的问题。设计实验验证了基于运动学的方法能以符合实际操作的效果完成虚拟现实系统中的操作任务，可以应用到虚拟训练、虚拟装配等仿真平台。     

Interactive movie elements in a pervasive game

This paper presents our research initiatives around new user experiences in the area of pervasive mixed reality crossmedia gaming. In a prototypical game, The Epidemic Menace, we combined static and interactive story telling elements to create a mixed reality experience. As part of this research initiative we also investigated how elements of the real world and virtual worlds could produce a new environment where physical and digital objects can co-exist and interact with each other, we wanted to evaluate how linear stories could be integrated into a game flow and how they could be used to extend game experiences. A new form of interactive entertainment that is not limited to hardware based games or linear storylines but includes a truly interactive TV experience was one of our goals.     

Context-Aware Mixed Reality: A Learning-Based Framework for Semantic-Level Interaction

Mixed reality (MR) is a powerful interactive technology for new types of user experience. We present a semantic-based interactive MR framework that is beyond current geometry-based approaches, offering a step change in generating high-level context-aware interactions. Our key insight is that by building semantic understanding in MR, we can develop a system that not only greatly enhances user experience through object-specific behaviours, but also it paves the way for solving complex interaction design challenges. In this paper, our proposed framework generates semantic properties of the real-world environment through a dense scene reconstruction and deep image understanding scheme. We demonstrate our approach by developing a material-aware prototype system for context-aware physical interactions between the real and virtual objects. Quantitative and qualitative evaluation results show that the framework delivers accurate and consistent semantic information in an interactive MR environment, providing effective real-time semantic-level interactions.     

视触觉融合的增强现实三维注册方法

增强现实技术是近年来人机交互领域的研究热点.在增强现实环境下加入触觉感知,可使用户在真实场景中看到并感知到虚拟对象.为了实现增强现实环境下与虚拟对象之间更加自然的交互,提出一种视触觉融合的三维注册方法.基于图像视觉技术获得三维注册矩阵;借助空间转换关系求解出触觉空间与图像空间的转换关系;结合两者与摄像头空间的关系实现视...     

Vision‐tangible interactive display method for mixed and virtual reality: Toward the human‐centered editable reality

Building a human‐centered editable world can be fully realized in a virtual environment. Both mixed reality (MR) and virtual reality (VR) are feasible solutions to support the attribute of edition. Based on the current development of MR and VR, we present the vision‐tangible interactive display method and its implementation in both MR and VR. We address the issue of MR and VR together because they are similar regarding the proposed method. The editable mixed and virtual reality system is useful for studies, which exploit it as a platform. In this paper, we construct a virtual reality environment based on the Oculus Rift, and an MR system based on a binocular optical see‐through head‐mounted display. In the MR system about manipulating the Rubik's cube, and the VR system about deforming the virtual objects, the proposed vision‐tangible interactive display method is utilized to provide users with a more immersive environment. Experimental results indicate that the vision‐tangible interactive display method can improve the user experience and can be a promising way to make the virtual environment better.     

增强现实:特点、关键技术和应用

增强现实(Augmented Reality，AR)技术将计算机生成的虚拟对象与真实世界进行融合，构造出虚实结合的虚拟空间增强现实系统有三个特点：真实和虚拟结合，实时交互，真实和虚拟对象进行定位构造一个AR系统要解决许多关键技术，包括显示技术，跟踪和定位技术，界面技术以及标定技术另外AR系统还要充分考虑人的因素AR技术在许多方面都有潜在的应用价值，如医疗，机械维护和修理，注释，协同，商业以及军事应用等本文对这些问题进行论述，最后讨论为使AR广泛使用需要解决的一些问题。     

基于数字孪生的智能车间系统仿真加速测试方法

为解决当前制造系统软件可靠性仿真测试时间长、测试环境难以搭建等问题,提出采用数字孪生技术与智能车间系统仿真加速测试相结合的方法;建立智能车间高保真数字孪生模型替代现实生产车间系统用于制造系统软件的可靠性仿真测试,首先要构建包含产品、设备资源、工艺流程等系统级仿真模型;同时,为仿真车间生产事件流程,在模型中,还需结合生产实际情况,设置设备间通信协议、通信数据以及生产线事件及队列顺序,真实模拟系统运行环境;通过构建步进电机产线数字孪生模型,仿真加工装配流程,运行智能车间系统软件,采用仿真时钟推进机制开展加速测试,验证了该方法的有效性和实用性,对开展工业系统软件高保真快速测试评估具有一定的借鉴意义。     

Eigen-Texture method: appearance compression and synthesis based ona 3D model

Image-based and model-based methods are two representative rendering methods for generating virtual images of objects from their real images. However, both methods still have several drawbacks when we attempt to apply them to mixed reality where we integrate virtual images with real background images. To overcome these difficulties, we propose a new method, which we refer to as the Eigen-Texture method. The proposed method samples appearances of a real object under various illumination and viewing conditions, and compresses them in the 2D coordinate system defined on the 3D model surface generated from a sequence of range images. The Eigen-Texture method is an example of a view-dependent texturing approach which combines the advantages of image-based and model-based approaches. No reflectance analysis of the object surface is needed, while an accurate 3D geometric model facilitates integration with other scenes. The paper describes the method and reports on its implementation     

基于Krpano的全景校园漫游的设计与实现

在数字校园建设和发展中,以虚拟全景校园漫游为基础的校园信息化平台能够为师生提供全新的沉浸式浏览体验,并提供更集中的信息交互功能.虚拟现实技术能够真实地再现现实环境,通过交互式操作,用户可以获得与真实环境相似的感受和体验,其中全景漫游是虚拟现实技术的一种典型应用.该文以南开大学滨海学院为实践区域,基于Krpano平台,利...     

虚拟现实技术与虚拟校园的研究与实践——以潍坊学院虚拟校园建设为例

虚拟现实技术为基础的虚拟校园研究是数字化校园建设的重要内容。以潍坊学院的实景校园为研究对象,采用具有针对性的三维建模和渲染技术,构建逼真的校园环境。建立了虚拟校园的结构框架及功能模块。结合虚拟现实技术、多媒体技术和网络技术构建了虚拟校园系统,实现了虚拟校园交互式导航与网络发布和运行。     

数字艺术作用下真实与形象的分裂

文章从广告艺术、媒体艺术、商业艺术这三个方面初步阐述数字艺术作用下真实与形象的分裂。虽然形象遮蔽了“真实”,分离了“真实”,但数字艺术掩盖了媒介在传播中实现的这种分离,数字技术制造的虚拟现实逼真的复制能力正潜移默化的促成这种分离的加剧。当数字艺术和数字技术利用视觉、触觉的高度仿真来欺骗人类的神经时,“真实”躲进了幕后。数字化诞生的数字形象是分裂的产物,构筑着数字系统里的虚拟现实。     

Interactive 3D content insertion in images for multimedia applications

This article addresses the problem of creating interactive mixed reality applications where virtual objects interact in images of real world scenarios. This is relevant to create games and architectural or space planning applications that interact with visual elements in the images such as walls, floors and empty spaces. These scenarios are intended to be captured by the users with regular cameras or using previously taken photographs. Introducing virtual objects in photographs presents several challenges, such as pose estimation and the creation of a visually correct interaction between virtual objects and the boundaries of the scene. The two main research questions addressed in this article include, the study of the feasibility of creating interactive augmented reality (AR) applications where virtual objects interact in a real world scenario using the image detected high-level features and, also, verifying if untrained users are capable and motivated enough to perform AR initialization steps. The proposed system detects the scene automatically from an image with additional features obtained using basic annotations from the user. This operation is significantly simple to accommodate the needs of non-expert users. The system analyzes one or more photos captured by the user and detects high-level features such as vanishing points, floor and scene orientation. Using these features it will be possible to create mixed and augmented reality applications where the user interactively introduces virtual objects that blend with the picture in real time and respond to the physical environment. To validate the solution several system tests are described and compared using available external image datasets.