Using relief texture for interactive and tangible virtual environments

This paper first introduces a way to improve interactivity with high polygon count virtual objects through the "mixed" use of image-based representation within one object. That is, both 3D polygonal and image-based representations are maintained for an object, and switched for rendering depending on the functional requirement of the object. Furthermore, in order to reduce the popping effect and provide smooth and gradual transition during the object representation switch, the object is subdivided with the subdivided parts possibly represented differently, i.e., using 3D models or images. As for the image-based representation, the relief texture (RT) method is used. In particular, through the use of the mixed representation, a new way called TangibleScreen is pro-posed to provide object tangibility by associating the image-based representation with a physical prop (projecting the RTs) in a selective and flexible way. Overall, the proposed method provides a way to maintain an interactive frame rate with selective perceptual details in a large-scale virtual environment, while allowing the user to interact with virtual objects in a tangible way.

Effects of virtual agents on interaction efficiency and environmental immersion in MR environments

Background Physical entity interactions in mixed reality(MR)environments aim to harness human capabilities in manipulating physical objects,thereby enhancing virtual environment(VEs)functionality.In MR,a common strategy is to use virtual agents as substitutes for physical entities,balancing interaction efficiency with environmental immersion.However,the impact of virtual agent size and form on interaction performance remains unclear.Methods Two experiments were conducted to explore how virtual agent size and form affect interaction performance,immersion,and preference in MR environments.The first experiment assessed five virtual agent sizes(25%,50%,75%,100%,and 125%of physical size).The second experiment tested four types of frames(no frame,consistent frame,half frame,and surrounding frame)across all agent sizes.Participants,utilizing a head mounted display,performed tasks involving moving cups,typing words,and using a mouse.They completed questionnaires assessing aspects such as the virtual environment effects,interaction effects,collision concerns,and preferences.Results Results from the first experiment revealed that agents matching physical object size produced the best overall performance.The second experiment demonstrated that consistent framing notably enhances interaction accuracy and speed but reduces immersion.To balance efficiency and immersion,frameless agents matching physical object sizes were deemed optimal.Conclusions Virtual agents matching physical entity sizes enhance user experience and interaction performance.Conversely,familiar frames from 2D interfaces detrimentally affect interaction and immersion in virtual spaces.This study provides valuable insights for the future development of MR systems.

Effective Learner-Lecturer Interaction Working With a Virtual Learning Environment

Using the Internet to learn a language creates wide opportunities to enhance learning （Association of teachers of English in Catalonia （APAC）, 2010）. The Internet activities promote learners＇ self-monitoring ability, encourage the use of multimedia and network technology, and develop students＇ cooperation and participation. During the latest years, there have been many changes in education as these new technologies, including VLEs （Virtual Learning Environments）, which have become an important part in the teaching/learning process. According to Tech Terms Computer Dictionary （2012）, VLE is a virtual classroom where teachers and students communicate. VLEs have evolved as at an early stage, they were only ways of transmitting information： Teachers uploaded the multimedia resources and students read this information. At a higher stage, VLEs have become interactive. This means that students become active. We have designed a virtual environment where students, weekly, must contribute their opinions and comments in response to a required activity uploaded by the teacher. In this paper, we describe this weekly task and analyze students＇ opinion about this planned activity. The students become an active subject in this field. In this paper, we show how VLEs are no longer a means of transmitting information but a means of interaction as well as a way of motivating our students to be involved in their learning process

IVE中虚拟人行为控制模型的研究与设计

对IVE中虚拟人行为控制模型这一新的交叉课题的研究进行阐述,并对虚拟人模型的关键技术进行了讨论,分别提出了虚拟人简单行为建模与智能行为建模的方法,利用3DSMax和Virtools三维开发平台设计实现了一个的虚拟人行为控制模型实例,验证了提出的方法。

Research on Virtual Agent Perception Model

An intelligent virtual environment is described for training users in the operation of complex engineering systems. After analyzing the original model of virtual environment, a virtual agent perception model was put forward. The information layer was inserted into original virtual environment. The model classifies all kinds of information and offers a way for knowledge description of virtual environment, and contributes to set up feeling model for the Virtual Agent within virtual environment.

Training birdsong recognition using virtual reality

Background In mega-biodiverse environments,where different species are more likely to be heard than seen,species monitoring is generally performed using bioacoustics methodologies.Furthermore,since bird vocalizations are reasonable estimators of biodiversity,their monitoring is of great importance in the formulation of conservation policies.However,birdsong recognition is an arduous task that requires dedicated training in order to achieve mastery,which is costly in terms of time and money due to the lack of accessibility of relevant information in field trips or even specialized databases.Immersive technology based on virtual reality(VR)and spatial audio may improve species monitoring by enhancing information accessibility,interaction,and user engagement.Methods This study used spatial audio,a Bluetooth controller,and a head-mounted display(HMD)to conduct an immersive training experience in VR.Participants moved inside a virtual world using a Bluetooth controller,while their task was to recognize targeted birdsongs.We measured the accuracy of recognition and user engagement according to the User Engagement Scale.Results The experimental results revealed significantly higher engagement and accuracy for participants in the VR-based training system than in a traditional computer-based training system.All four dimensions of the user engagement scale received high ratings from the participants,suggesting that VR-based training provides a motivating and attractive environment for learning demanding tasks through appropriate design,exploiting the sensory system,and virtual reality interactivity.Conclusions The accuracy and engagement of the VR-based training system were significantly high when tested against traditional training.Future research will focus on developing a variety of realistic ecosystems and their associated birds to increase the information on newer bird species within the training system.Finally,the proposed VR-based training system must be tested with additional participants and for a longer duration to measure information recall and recognition mastery among users.

Design of finger gestures for locomotion in virtual reality

Background Within a virtual environment(VE)the control of locomotion(e.g.,self-travel)is critical for creating a realistic and functional experience.Usually the direction of locomotion,whileusing a head-mounted display(HMD),is determined by the direction the head is pointing and the forwardor backward motion is controlled with a hand held controllers.However,hand held devices can be difficultto use while the eyes are covered with a HMD.Free hand gestures,that are tracked with a camera or ahand data glove,have an advantage of eliminating the need to look at the hand controller but the design ofhand or finger gestures for this purpose has not been well developed.Methods This study used a depth-sensing camera to track fingertip location(curling and straightening the fingers),which was converted toforward or backward self-travel in the VE.Fingertip position was converted to self-travel velocity using amapping function with three parameters:a region of zero velocity(dead zone)around the relaxed handposition,a linear relationship of fingertip position to velocity(slope orβ)beginning at the edge of the deadzone,and an exponential relationship rather than a linear one mapping fingertip position to velocity(exponent).Using a HMD,participants moved forward along a virtual road and stopped at a target on theroad by controlling self-travel velocity with finger flexion and extension.Each of the 3 mapping functionparameters was tested at 3 levels.Outcomes measured included usability ratings,fatigue,nausea,and timeto complete the tasks.Results Twenty subjects participated but five did not complete the study due tonausea.The size of the dead zone had little effect on performance or usability.Subjects preferred lower β values which were associated with better subjective ratings of control and reduced time to complete thetask,especially for large targets.Exponent values of 1.0 or greater were preferred and reduced the time tocomplete the task,especially for small targets.Conclusions Small finger movements can be used tocontrol velocity of self-travel in VE.The functions used for converting fingertip position to movementvelocity influence usability and performance.

Lessons learned from requirements gathering for virtual reality simulators

Background This paper shows how current collaborative virtual environments(VEs)such as Mozilla Hubs and AltspaceVR can aid in the task of requirements gathering in VR for simulation and training.Methods We performed a qualitative study on our use of these technologies in the requirements gathering of two projects.Results Our results show that requirements gathering in virtual reality has an impact on the process of requirements identification.We report advantages and shortcomings that will be of interest to future practitioners.For example,we found that VR sessions for requirements gathering in current VEs could benefit from better pointers and better sound quality.Conclusion Current VEs are useful for the requirements gathering task in the development of VR simulators and VR training environments.

玉米收获机虚拟样机的仿真作业研究

为了实现玉米收获机在虚拟环境中的工况仿真与性能测试,设计了虚拟仿真系统。首先,建立VR工况环境,采用数字函数建立地形模型和地高模型,采用外部引用、实例化和布告板技术实现地物模型;其次,建立收获机运行模型,其中发动机有效功率与转速呈线性分布,有效扭矩与转速成二次关系,建立转向控制模型和制动模型;基于ODE物理引擎建立收获机自身部件相对运动建模,进而完成收获机模型和VR工况模型的交互系统;最后,在虚拟环境中对收获机进行测试,指导改进收获机设计。

基于激光测距仪的智能物联网体感交互感知研究

当前的智能物联网设备在识别用户指令方面存在不足,时常需要用户多次尝试,降低了用户的使用体验和对设备的信任度。为了解决问题,提出了一种基于激光测距仪的智能物联网体感交互感知方法。首先,拟合激光波绘制结果,并利用距离变换算法设定智能物联网的体感交互方式。然后,通过误差传递公式,计算激光测距仪的协方差矩阵,依据此调整参数和测量点。最后,融合激光图像特征,识别操作者的动态指令。实验结果表明,所提方法能够显著提升智能物联网设备对体感指令的采集完整度,正确完成所有体感指令,且平均体感动作类别划分精准度高达97.02%,说明所提方法具有较高的体感交互感知精度。

Immersive visualization of 3D subsurface ground model developed from sparse boreholes using virtual reality(VR)

Analytics and visualization of multi-dimensional and complex geo-data,such as three-dimensional(3D)subsurface ground models,is critical for development of underground space and design and construction of underground structures(e.g.,tunnels,dams,and slopes)in engineering practices.Although complicated 3D subsurface ground models now can be developed from site investigation data(e.g.,boreholes)which is often sparse in practice,it remains a great challenge to visualize a 3D subsurface ground model with sophisticated stratigraphic variations by conventional two-dimensional(2D)geological cross-sections.Virtual reality(VR)technology,which has an attractive capability of constructing a virtual environment that links to the physical world,has been rapidly developed and applied to visualization in various disciplines recently.Leveraging on the rapid development of VR,this study proposes a framework for immersive visualization of 3D subsurface ground models in geo-applications using VR technology.The 3D subsurface model is first developed from limited borehole data in a data-driven manner.Then,a VR system is developed using related software and hardware devices currently available in the markets for immersive visualization and interaction with the developed 3D subsurface ground model.The results demonstrate that VR visualization of the 3D subsurface ground model in an immersive environment has great potential in revolutionizing the geo-practices from 2D cross-sections to a 3D immersive virtual environment in digital era,particularly for the emerging digital twins.

Measuring user preferences and behaviour in a topographic immersive virtual environment(TopoIVE)of 2D and 3D urban topographic data

This paper investigates user preferences and behaviour associated with 2D and 3D modes of urban representation within a novel Topographic Immersive Virtual Environment(TopoIVE)created from official 1:10,000 mapping.Sixty participants were divided into two groups:the first were given a navigational task within a simulated city and the second were given the freedom to explore it.A Head-Mounted Display(HMD)Virtual Reality(VR)app allowed participants to switch between 2D and 3D representations of buildings with a remote controller and their use of these modes during the experiment was recorded.Participants performed mental rotation tests before entering the TopoIVE and were interviewed afterwards about their experiences using the app.The results indicate that participants preferred the 3D mode of representation overall,although preference for the 2D mode was slightly higher amongst those undertaking the navigational task,and reveal that different wayfinding solutions were adopted by participants according to their gender.Overall,the findings suggest that users exploit different aspects of 2D and 3D modes of visualization in their wayfinding strategy,regardless of their task.The potential to combine the functionality of 2D and 3D modes therefore offers substantial opportunities for the development of immersive virtual reality products derived from topographic datasets.

基于虚拟仿真技术的农业机械交互展示设计

虚拟仿真技术作为一项进入21世纪以来才逐步发展并完善起来的新型实用技术,可以对现实场景进行全面仿真,在农业机械设计中有着广阔的应用前景。农业机械设计搭载虚拟仿真技术可以精准且有效地掌握客户实际需求,缩短机械设计方案周期,在成本最小化的前提下实现设计质量最优化目标,能够为用户提供更加有效与直观的设计方案。为此,以农业机械设计为主体,将虚拟仿真技术与农业机械设计相互结合,基于沉浸式、交互式和构想式原则,在交互展示系统的设计上构建农机的三维模型,并利用Web 3D实现了农业机械网络化在线展示。研究结果可为推动农业机械产品的设计与优化提供技术参考,对于扩展虚拟现实技术在农业机械中的应用具有现实意义。

走向多模态:虚拟现实学习活动的价值路向

随着虚拟现实交互技术与可穿戴设备的不断更新与发展,虚拟现实学习活动能够有效调动学习者的多感官参与,开展多模态学习活动。针对当前虚拟现实学习活动面临沉浸感的缺失、场景的实践价值遮蔽以及数据的局限性表征等现实困境,通过对虚拟现实多模态学习活动进行内涵解析,挖掘其在学习内容层面的多态资源增强身心体验、学习过程层面的具身交互深化实践应用以及学习评价层面的多维数据构建精准画像等内在价值。并基于上述分析从资源层、交互层与评价层等三个层次来构建虚拟现实多模态学习活动的开展框架:依据知识类型开展虚拟现实多模态学习资源设计;依据具身层次进行虚拟现实多模态交互学习活动;依据多维数据进行虚拟现实多模态学习活动评价。

Real-time interactive motion control of virtual human in virtual maintenance based on limited information

In order to provide a simple and efficient approach to perform the real-time interactive motion control of virtual human in virtual maintenance environment(VME),the motion control method of virtual human based on limited input information is proposed.With the space position tracking system with only one sensor the action sequences and motion models of virtual human,the human motions and hand actions in VME are driven by the sensor data in stages and in real time through the transmission condition control in the process of maintenance operation.And the input data and information is processed based on the method of Kalman filtering and wavelet transforming to improve the control effects.An experimental VME is also established to validate the control efficiency,and the experiment results show that the space motion control of virtual human in VME can be performed based on limited information with proposed control strategy.

汽车维修虚拟仿真技术的创新与实践

随着汽车工业的快速发展,现代汽车技术变得越来越复杂,传统的维修模式往往依赖于实车操作,不仅成本高昂,且存在安全风险,还受到实际操作空间和设备数量的限制。为了解决这些问题,汽车维修虚拟仿真技术应运而生,通过先进的计算机仿真和虚拟现实手段,提供一个高效、安全且成本可控的维修环境。本文针对汽车维修虚拟仿真技术的创新与实践路径展开详细分析,为进一步提高汽车维修质量提供技术支持。

虚拟环境下基于语义的三维交互技术

自然、高效的三维交互技术是虚拟现实系统成功应用的关键.现有的交互技术主要是从几何层次上考虑如何有效实现交互任务,而对面向高层应用的交互任务的支持还不够.借鉴人类在真实世界中的认知原理,虚拟环境中的交互对象不仅具有外观意义上的几何属性,而且包含了与交互有关的规则、约束和供给等语义属性,这些虚拟对象称为语义对象.在系统导航、对象选择/操作等交互任务的执行中,通过语义对象可以实现高层交互语义的封装和解析.从应用角度提高交互技术的效率和可用性,为用户提供“直接操纵”之上的面向高层语义的交互隐喻,屏蔽交互技术的底层实现细节,使用户专注于应用领域相关的高层交互控制.

虚拟现实技术及应用

虚拟现实是计算机科学和信息科学的交叉和融合 ,被认为是 2 1世纪信息科学领域最有发展前途的技术 ,目前已得到国内外学术界的普遍关注。该文介绍了虚拟现实技术的基本概念 ,论述了虚拟现实技术理论、构成虚拟现实系统的软硬件技术、虚拟现实技术的发展现状和关键技术 ,以及虚拟现实技术的应用领域。

虚拟作战战场环境的研究与实现

介绍了构建以解放战争某著名战役为背景的虚拟战场环境的关键技术,包括虚拟战场环境的结构组成、仿真模型、仿真管理和想定生成、场景管理、虚拟士兵的行为表示、实时战场环境声音仿真、人机交互方式等。在此基础上,介绍了已研制完成的基于多PC机联网具有沉浸与交互特征的多用户同时参与的含虚拟士兵的虚拟作战演示与观众参与系统。