增强现实环境快速重建系统研究

针对现有增强现实技术在进行环境重建时存在环境重建时间长、设备门槛高、户外环境重建定位困难等问题，设计并实现了AR环境快速重建系统。以谷歌ARCore作为开发基础，调用环境信息估算工具获取三维模型空间坐标和环境深度信息；设计一种新的多重目标跟踪匹配算法，以解析目标特征，并与三维模型生成对应关系；加入北斗全球卫星信号（global navigation satellite system,GNSS）接收机对原有的定位模块进行改进，采用参数转换法对高精度坐标进行本地化处理；使用分割位姿匹配法校正环境中的三维模型重建位姿。实验结果证明，该改进系统适用范围广，拥有脱离摄像头后AR环境不丢失位置等特点，增强了AR环境重建中用户的方位感知能力，降低了AR环境中不同三维模型和目标特征的匹配处理难度。     

基于KCF与改进ORB的增强现实方法

针对增强现实(AR)系统在进行虚拟信息叠加时待注册区域被遮挡的情况,提出一种基于实时特征检测与目标跟踪的AR系统三维注册方法。使用KCF算法对待注册目标区域与模板进行实时FAST特征匹配,通过改进ORB算法,提出SIFT-ORB-MRANSAC融合算法,完成特征点的提取、匹配以及误匹配去除。在此基础上,根据特征点之间的匹配关系计算注册矩阵,通过注册矩阵叠加虚拟信息实现对现实世界的增强。实验结果表明,该方法在光照变化、遮挡以及旋转变换的情况下,可将虚拟信息快速、准确地叠加到待注册区域,提高AR系统的运算效率。     

基于增强现实的线缆装配引导系统研究

针对传统航空航天线缆装配过程中存在对工艺规程研读不便利、出错概率大、装配人员的智力负担重等问题,提出基于增强现实的线缆装配引导系统研究。对基于AR的线缆装配引导系统总体框架进行详细论述;对该系统算法思想与工作流程进行研究;开发基于AR的线缆装配引导原型系统,将所提出的算法在该原型系统中进行实例验证。实验结果表明,基于AR的线缆装配引导系统很大程度上为解决传统航空航天线缆装配带来的缺陷,提供了一个新途径。     

AR场景中的基础态势数据展示与优化

随着增强现实(AR)设备的发展,增强态势已经成为其主要应用点.由于AR设备计算能力和图像处理能力的不足,存在场景生成速度慢和视野狭窄等问题.基于AR设备上的态势信息显示应用和设备地理信息场景显示功能的实现,本文对地形分块化算法进行优化,并提出一种自适应Mesh区域化算法来解决上述问题.对所提出的算法、传统地形生成算法和...     

支持装配引导的单手指手势交互方法

工业装配引导增强现实(AR)系统使用鼠标键盘等传统交互方法,难以在启动装配任务和执行装配操作之间实现无缝装配引导。为解决该问题,提出一种基于Color Predicate的单手指手势交互方法,将该方法与ARToolKit标识板系统相结合,开发堆积木部件装配引导增强现实演示系统。应用和分析结果表明,该方法在室内环境下具有较好的鲁棒性,在 AR 装配应用中能够无缝引导用户快速完成部件装配任务。     

AR技术在科技馆古代农具展示中的研究及实现

增强现实技术将虚拟与现实有机结合,突破了虚拟世界和现实世界的界限。针对增强现实技术的特点,研究了一套实现增强现实系统的框架。首先对场景进行采集,使用3D Max对模型进行设计并建模;针对图像识别的问题,通过对比SIFT算法、SURF算法、ORB算法以及高通Vuforia的特征识别匹配的结果,选择高通Vuforia处理图像;3D渲染则使用专业渲染引擎Unity3D实现增强现实中交互软件的开发。基于此框架设计并实现一个以科技馆古代农具展示为主题的系统,能够带给参观者AR交互阅读的全新体验;可以再现我国古代农具在传统农业文化传承的重要史料,从而实现对古代农具文物的数字化保护和传播。     

自适应采样与融合的增强现实阴影生成算法

针对现有增强现实(AR)应用中阴影生成算法绘制软阴影的真实性不足,提出一种自适应采样与背景融合的阴影生成算法。首先结合考虑遮挡的平面阴影算法计算虚拟对象投影阴影的空间位置分布;其次,改进膨胀腐蚀算法中软阴影的生成过程,提出一种依据近似点光源的形状类型进行自适应采样,从而获取假想点光源集合的软阴影绘制方法;最后,针对基于膨胀腐蚀算法使用阴影灰度图方法造成阴影的颜色被限制在单通道上,提出基于多通道与背景融合的方法。实验结果表明所提算法计算软阴影的颜色更加合理,软阴影的绘制方法更为有效,提高了阴影生成算法绘制软阴影的真实性。     

AR翻转诗词

随着计算机技术的不断进步,增强现实技术(AR)迅速地成长了起来,从实验室走向社会,从面世之初的青涩走向成熟,AR的使用日趋频繁."虚拟实验平台"、"线上博物馆"、"扫五福"……AR逐渐进入了人们的生活中并深受大家喜爱.诗词歌赋作为中国古典传统文化的代表,在中华文明中发挥着重要的作用.但由于一些诗句描写叙述隐晦含蓄,帮助学习者更好地理解诗词是非常重要的.介绍了一个将增强现实技术应用到诗词学习中进行场景还原的诗词辅助学习系统,以此带给学习者在诗词学习方面更好的体验.     

基于增强现实与异型屏实时互动系统的研究*

提出并实现了一种基于增强现实的多人实时互动的平台和系统。首次提出了在展览展示领域融合应用AR技术与多异型屏技术,研究并实现了AR系统多人实时互动相关技术,设计了AR交互系统的渲染平台、交互平台和网络通信平台。提出利用人工免疫算法解决AR系统实时碰撞检测的问题。系统将在世博会进行展示应用,具有良好的技术与经济效益前景。     

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。     

增强现实系统中磁力跟踪注册的精确性研究

为进一步提高增强现实系统的三维注册精度,分析了磁力跟踪系统误差产生原因,在坐标变换校正法的基础上,提出了一种自适应网格线性插值校正法,对跟踪器进行校正.该方法首先将系统所用的整个三维空间划分为空间网格,再建立磁力坐标与真实坐标的对应表,然后对网格进行自适应重划分,最后利用线性插值法对实时磁力坐标进行校正.对该方法进行了详细的分析说明,进行了相关实验,实验结果表明,该方法能够显著提高增强现实系统的跟踪精确度,使虚实结合更自然.     

增强现实系统中基于先验知识的虚拟抓取识别

为了实现增强现实系统中抓取动作的识别,针对传统方法实时性不强、容易产生误判的不足,提出了基于先验知识的虚拟抓取识别算法.通过对大量实验数据的分析,提取关键数据进行处理并完成决策树的构建,通过基于一种数据拟合的碰撞检测方法,真正实现了真实手对虚拟对象的抓取识别.实验结果表明:该算法识别率高、实时性好、交互自然真实,较好地...     

The effects of an augmented reality based magnetic experimental tool on students' knowledge improvement and cognitive load

While the use of experiments is important for developing students' scientific knowledge and skills, challenges may arise when teachers and students are conducting experiments in class, such as non-reusable experimental resources, safety issues and difficulties simulating some specific effects. Augmented reality (AR) technology affords an alternative approach to conducting experiments by bringing students a virtual–real mixed learning environment. In this study, taking junior high school physics knowledge on the magnetic field as an example, we designed and developed an AR-based mobile simulated experiment tool. This study investigates the effect of the AR-based experiment on students' knowledge improvement and cognitive load compared with 3D and traditional experiments. A sample of 122 ninth-grade students was randomly chosen and assigned to three groups (AR, 3D and Traditional). The results demonstrate that students in the AR group performed better than those in the 3D and Traditional groups in terms of their knowledge improvement. The AR group students also experienced the lowest cognitive load among the three groups. Moreover, students had positive perceptions about AR and 3D tools. The implications of this study are discussed.     

增强现实三维注册中标识点匹配算法研究与改进

基于标识点的增强现实系统中,计算机生成的虚拟物体需要正确地注册到相应的标识点上构成对现实环境的增强.针对增强现实三维注册过程中传统算法标识点匹配过程中误识率较高,匹配不够精确的不足,提出了将相对误差法进行改进实现增强现实中的三维注册,同时提出了将基于颜色直方图的图像匹配原理引入增强现实的三维注册过程中,通过实验验证与分析,改进后的匹配算法与传统算法相比减少了标识的误识率,提高了注册精度,已成功应用于增强现实系统的三维注册过程中.     

EcoMOBILE: Integrating augmented reality and probeware with environmental education field trips

Positioned in the context of situated learning theory, the EcoMOBILE project combines an augmented reality (AR) experience with use of environmental probeware during a field trip to a local pond environment. Activities combining these two technologies were designed to address ecosystem science learning goals for middle school students, and aid in their understanding and interpretation of water quality measurements. The intervention was conducted with five classes of sixth graders from a northeastern school district as a pilot study for the larger EcoMOBILE project, and included pre-field trip training, a field trip to a local pond environment, and post-field trip discussions in the classroom.During the field experience, students used mobile wireless devices with FreshAiR™, an augmented reality application, to navigate the pond environment and to observe virtual media and information overlaid on the physical pond. This AR experience was combined with probeware, in that students collected water quality measurements at designated AR hotspots during the experience. We studied the characteristics of learning and instruction using measures of student attitudes, content learning gains, and opinions teachers provided via written and verbal feedback. We observed gains in student affective measures and content understanding following the intervention. Teachers reported that the combined technologies promoted student interaction with the pond and with classmates in a format that was student-centered rather than teacher-directed. Teachers also reported that students demonstrated deeper understanding of the principles of water quality measurement than was typical on prior field trips without these technologies and that students had expanded opportunities to engage in activities that resemble scientific practice. Overall, results of the students' surveys and teacher feedback suggest that there are multiple benefits to using this suite of technologies for teaching and for learning.     

A 3D GIS-based interactive registration mechanism for outdoor augmented reality system

Registering virtual objects with reference to their corresponding real-world objects plays a key role in augmented reality (AR) system. Although there have been a lot of work on using vision-based method to perform registration for indoor AR system, it is very difficult to apply such registration method for outdoor AR system due to the inability to modify the objects in outdoor environment and the huge range of working area. 3D Geographic Information System (GIS) is capable of providing an outdoor virtual geographic environment where users are located at, which may provide users with a corresponding virtual object for the one in the physical world. In this study, a 3D GIS-based registration mechanism is proposed for outdoor AR system. Specifically, an easy-use interactive method for precise registration was developed to improve the performance of the registration. To implement the registration mechanism, an outdoor AR system built upon 3D GIS was developed, named Augmented Reality Geographical Information System (ARGIS). ARGIS has the capability of performing precise registration in outdoor environment without using traditional vision tracking method, which thus enables users to arbitrarily manipulate the system. A prototype was developed to conduct experiment on the campus of Peking University, Beijing, China to test the proposed registration mechanism. The experiment shows that the developed registration mechanism is feasible and efficient in the outdoor environment. The ARGIS is expected to enrich the applications of outdoor AR system, including but not limited to underground facility mapping, emergency rescue and urban planning.     

Impact of monitor-based augmented reality for on-site industrial manual operations

This work evaluates the impact of augmented reality (AR) technology to support operators during manual industrial tasks. The work focuses specifically on monitor-based augmented reality as a solution to provide instructions to the operator. Instructions are superimposed directly onto a video representation of the physical workspace and are displayed on a standard monitor. In contrast to previous AR solutions proposed to support manual tasks, the current work is more industrially acceptable because it meets most of the industrial requirements and it is cost effective for a deployment in an industrial environment. The developed prototype is described and evaluated by means of a user study to compare the monitor-based augmented reality solution to provide instructions and the traditional method. The test shows that AR can be a valid substitute to support the operators during manual tasks because it allows them to be more time efficient and it reduces their mental workload compared to traditional instructional manuals.     

Browsing the Real-World Wide Web: Maintaining Awareness of Virtual Information in an AR Information Space

The authors describe a prototype augmented reality (AR) system that allowed them to experiment with interfaces to a 3-dimensional spatialized information space based on the World Wide Web (WWW). The authors call such an information space the Real-World Wide Web (RWWW), because it merges the WWW with the physical world. They present the assumptions they make about the characteristics of such a system, discuss the implications of those assumptions for AR interfaces, and describe their initial experiences creating a prototype RWWW browser.     

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.

Gesture-based interactive augmented reality content authoring system using HMD

This paper proposes an augmented reality content authoring system that enables ordinary users who do not have programming capabilities to easily apply interactive features to virtual objects on a marker via gestures. The purpose of this system is to simplify augmented reality (AR) technology usage for ordinary users, especially parents and preschool children who are unfamiliar with AR technology. The system provides an immersive AR environment with a head-mounted display and recognizes users’ gestures via an RGB-D camera. Users can freely create the AR content that they will be using without any special programming ability simply by connecting virtual objects stored in a database to the system. Following recognition of the marker via the system’s RGB-D camera worn by the user, he/she can apply various interactive features to the marker-based AR content using simple gestures. Interactive features applied to AR content can enlarge, shrink, rotate, and transfer virtual objects with hand gestures. In addition to this gesture-interactive feature, the proposed system also allows for tangible interaction using markers. The AR content that the user edits is stored in a database, and is retrieved whenever the markers are recognized. The results of comparative experiments conducted indicate that the proposed system is easier to use and has a higher interaction satisfaction level than AR environments such as fixed-monitor and touch-based interaction on mobile screens.