MagicMeeting: A Collaborative Tangible Augmented Reality System

We describe an augmented reality (AR) system that allows multiple participants to interact with 2D and 3D data using tangible user interfaces. The system features face-to-face communication, collaborative viewing and manipulation of 3D models, and seamless access to 2D desktop applications within the shared 3D space. All virtual content, including 3D models and 2D desktop windows, is attached to tracked physical objects in order to leverage the efficiencies of natural two-handed manipulation. The presence of 2D desktop space within 3D facilitates data exchange between the two realms, enables control of 3D information by 2D applications, and generally increases productivity by providing access to familiar tools. We present a general concept for a collaborative tangible AR system, including a comprehensive set of interaction techniques, a distributed hardware setup, and a component-based software architecture that can be flexibly configured using XML. We show the validity of our concept with an implementation of an application scenario from the automotive industry.     

Communication Behaviors in Colocated Collaborative AR Interfaces

The authors present an analysis of communication behavior in face-to-face collaboration using a multi-user augmented reality (AR) interface. 2 experiments were conducted. In the 1st experiment, collaboration with AR technology was compared with more traditional unmediated and screen-based collaboration. In the 2nd experiment, the authors compared collaboration with 3 different AR displays. Several measures were used to analyze communication behavior, and the authors found that users exhibited many of the same behaviors in a collaborative AR interface as in face-to-face unmediated collaboration. However, user communication behavior changed with the type of AR display used. The authors describe implications of these results for the design of collaborative AR interfaces and directions for future research.     

Spatial conferencing using a wearable computer

Wearable computers provide constant access to computing and communications resources; however, there are many unanswered questions as to how this computing power can be used to enhance communication. We describe a wearable augmented reality communication space that uses spatialised 3D graphics and audio cues to aid communication. The user is surrounded by virtual avatars of the remote collaborators that they can interact with using natural head and body motions. The use of spatial cues means that the conferencing space can potentially support dozens of simultaneous users. We report on two experiments that show users can understand speakers better with spatial rather than non-spatial audio, and that minimal visual cues may be sufficient to distinguish between speakers. Additional informal user studies with real conference participants suggest that wearable communication spaces may offer significant advantages over traditional communication devices.     

“Studierstube”: An environment for collaboration in augmented reality

We propose an architecture for multi-user augmented reality with applications in visualisation, presentation and education, which we call Studierstube. Our system presents three-dimensional stereoscopic graphics simultaneously to a group of users wearing light weight see-through head mounted displays. The displays do not affect natural communication and interaction, making working together very effective. Users see the same spatially aligned model, but can independently control their viewpoint and different layers of the data to be displayed. The setup serves computer supported cooperative work and enhances cooperation of visualisation experts. This paper presents the client-server software architecture underlying this system and details that must be addressed to create a high-quality augmented reality setup.     

语义驱动下水面场景中AR效果提升方法

增强现实应用场景不断拓展,但水面检测领域由于物理光学的反射等特性的影响制约了水面增强现实的应用.对此提出一种语义驱动下的基于ORB-SLAM2系统在水面场景下进行实时增强现实效果提升的方法.将视频帧传入深度学习语义分割网络ICNet中,把分割后得到的标签图和原视频帧一同输入SLAM系统的前端进行追踪及地图构建.在语义的...     

A new AR authoring tool using depth maps for industrial procedures

Several augmented reality systems have been proposed for different target fields such as medical, cultural heritage and military. However, most of the current AR authoring tools are actually programming interfaces that are exclusively suitable for programmers. In this paper, we propose an AR authoring tool which provides advanced visual effect, such as occlusion or media contents. This tool allows non-programming users to develop low-cost AR applications, specially oriented to on-site assembly and maintenance/repair tasks. A new 3D edition interface is proposed, using photos and Kinect depth information to improve 3D scenes composition. In order to validate our AR authoring tool, two evaluations have been performed, to test the authoring process and the task execution using AR. The evaluation results show that overlaying 3D instructions on the actual work pieces reduces the error rate for an assembly task by more than a 75%, particularly diminishing cumulative errors common in sequential procedures. Also, the results show how the new edition interface proposed, improves the 3D authoring process making possible create more accurate AR scenarios and 70% faster.     

增强现实系统中磁力跟踪器的校正

提出了利用BP神经网络对跟踪器进行校正。针对神经网络训练速度慢、容易陷入局部极值的情况，首先利用具有良好全局搜索能力的遗传算法来优化BP神经网络的各层初始权值和阈值，为后续神经网络的搜索定位出一个优化的搜索空间。实验结果表明，利用该遗传神经网络方法进行跟踪器校正，能够显著提高增强现实系统的精度，有助于提高增强现实系统的真实感。     

Occlusion in collaborative augmented environments

Augmented environments superimpose computer enhancements on the real world. Such augmented environments are well suited for collaboration of multiple users. To improve the quality and consistency of the augmentation the occlusion of real objects by computer-generated objects and vice versa has to be implemented. We present methods how this can be done for a tracked user's body and other real objects and how irritating artifacts due to misalignments can be reduced. Our method is based on simulating the occlusion of virtual objects by a representation of the user modeled as kinematic chains of articulated solids. Smoothing the border between virtual world and occluding real reduces registration and modeling errors of this model. Finally, an implementation in our augmented environment and the resulting improvements are presented.     

户外增强现实系统的关键技术研究

增强现实技术,特别是户外增强系统,近年来已经成为一大研究热点。论文研究了增强现实中的主要技术,分析了户外增强现实系统的关键技术,就听觉增强方面的未来发展等提出了自己的见解。     

An interactive virtual guide for the AR based visit of archaeological sites

One of the most interesting research lines about avatars is the design and the implementation of a synthetic behaviour able to drive avatar's actions according to an adaptive interaction paradigm. This aspect, indeed, is of fundamental importance to many advanced applications involving avatars and humans. This study presents a novel framework exploiting augmented reality to visualize a synthetic 3D virtual guide inside an exhibit or a public gallery, to assist visitors wearing a Head Mounted Display during their visit and providing them with both visual and informative enhancements not available in a standard tour. The Human–avatar interaction is approached through a model based on timed automata to address the conversational issues and to improve the quality of interaction by means of an effective synchronization. A usability study conducted on an application of this research to the “avatar assisted tour” of a roman villa, confirms the efficacy of the approach.     

Collaborative virtual sculpting with haptic feedback

This paper introduces a haptic virtual environment in which two users can collaboratively sculpt a virtual clay model, working from different physical locations connected by the internet. They view their virtual sculpting tools and the clay model in 3D, feel the tool’s pressure on the clay as they work, and have their hands co-located with the view of the tool and model. Since the sculptors have independent views of the same logical environment, they can work at different zoom levels, and be in different coordinate systems, even spinning ones, at the same time. This provides them with the capability to explore new styles of collaborative creativity, working off each other’s initiative where appropriate. The system was designed to allow unrestrained, asynchronous behaviour by the collaborating sculptors. The paper describes the hardware as well as the algorithms behind the deformability of the clay surface and the communications model enabling the distance collaboration. It gives an explanation of the simple conflict resolution mechanism that haptic feedback facilitates and also reports on the results of a qualitative study into the creativity benefits of such a collaborative system.     

Distributed and Collaborative Software Evolution Analysis with Churrasco

Analyzing the evolution of large and long-lived software systems is a complex problem that requires extensive tool support due to the amount and complexity of the data that needs to be processed. In this paper, we present Churrasco, a tool to support collaborative software evolution analysis through a web interface. After describing the tool and its architecture, we provide a usage scenario of Churrasco on a large open source software system, and we present two collaboration experiments performed with, respectively, 8 and 4 participants.     

基于增强现实技术的AR赛车游戏

AR赛车是一款融入了增强现实技术的3D赛车游戏。在赛车游戏中运用增强现实技术．使得游戏有了全新的控制方式和场景效果。在游戏控制方式上,玩家不再需要用键盘来控制赛车,而是通过在摄像头前操纵有特定标识图案的纸片来控制赛车;在场景效果上,AR赛车不再像传统游戏那样始终处于虚拟场景中,而是采用真实场景与虚拟物体相结合。这些特点将会给玩家带来全新的游戏体验。     

基于增强现实的机器人远程控制系统研究

虚拟现实技术的应用使远程控制系统得到发展,增强现实技术是虚拟现实技术的拓展,它将计算机生成的虚拟物体叠加到用户感知的真实世界中.提出并实现了一种基于增强现实的机器人远程控制系统,并就其结构和关键技术进行详细的说明,实验及运行结果表明该系统能有效地改善人机交互能力,并能提高远程控制的精度.     

Tracking for augmented reality on wearable computers

Wearable computers afford a degree of mobility that makes tracking for augmented reality difficult. This paper presents a novel object-centric tracking architecture for presenting augmented reality media in spatial relationships to objects, regardless of the objects' positions or motions in the world. The advance this system provides is the ability to sense and integrate new features into its tracking database, thereby extending the tracking region automatically. A lazy evaluation of the structure from motion problem uses images obtained from a single calibrated moving camera and applies recursive filtering to identify and estimate the 3D positions of new features. We evaluate the performance of two filters; a classic Extended Kalman Filter (EKF) and a filter based on a Recursive-Average of Covariances (RAC). Some implementation issues and results are discussed in conclusion.     

增强现实系统中的摄像机校准算法研究

增强现实系统的关键技术之一是精确定位问题,当用户改变他/她的观察视点时,虚拟对象必须与真实对象的运动方向与位置保持一致,这样才能使用户感觉到虚拟对象融入到真实环境中.而要做到这一点,就必须研究摄像机校准问题.在这篇文章中,我们分析了增强现实系统对摄像机校准算法的要求,给出了一个实用的摄像机校准算法,并且对算法的结果进行了具体分析.     

Tangled reality

Leonardo da Vinci was a strong advocate for using sketches to stimulate the human imagination. Sketching is often considered to be integral to the process of design, providing an open workspace for ideas. For these same reasons, children use sketching as a simple way to express visual ideas. By merging the abstraction of human drawings and the freedom of virtual reality with the tangibility of physical tokens, Tangled Reality creates a rich mixed reality workspace. Tangled Reality allows users to build virtual environments based on simple colored sketches and traverse them using physical vehicles overlayed with virtual imagery. This setup allows the user to “build” and “experience” mixed reality simulations without ever touching a standard computer interface.     

Human factors and qualitative pedagogical evaluation of a mobile augmented reality system for science education used by learners with physical disabilities

Technology-enhanced learning, employing novel forms of content representation and education service delivery by enhancing the visual perception of the real environment of the user, is favoured by proponents of educational inclusion for learners with physical disabilities. Such an augmented reality computer-mediated learning system has been developed as part of an EU funded research project, namely the CONNECT project. The CONNECT project brings together schools and science centres, and produces novel information and communication technologies based on augmented reality (AR) and web-based streaming and communication, in order to support learning in a variety of settings. The CONNECT AR interactive learning environment can assist users to better contextualize and reinforce their learning in school and in other settings where people learn (i.e. science centres and home). The CONNECT concept and associated technologies encourage users to visit science centres and perform experiments that are not possible in school. They can also build on these experiences back at school and at home with visual augmentations that they are communicated through web-based streaming technology. This paper particularly focuses on a user-centred evaluation approach of human factors and pedagogical aspects of the CONNECT system, as applied to a special needs user group. The main focus of the paper is on highlighting the human factors issues and challenges, in terms of wearability and technology acceptance, while elaborating on some qualitative aspects of the pedagogical effectiveness of the instructional medium that AR technology offers for this group of learners.