Virtual Reality

Publications in this journal

• Article: The Palenque project: evaluating interaction in an online virtual archaeology site

  Erik Champion, Ian Bishop, Bharat Dave
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  ABSTRACT: This case study evaluated the effect on cultural understanding of three different interaction modes, each teamed with a specific slice of the digitally reconstructed environment. The three interaction modes were derived from an initial descriptive theory of cultural learning as instruction, observation and action. A major aim was to ascertain whether task performance was similar to the development of understanding of the cultural context reached by participation in the virtual environment. A hypothesis was that if task performance is equivalent to understanding and engagement, we might be able to evaluate the success of virtual heritage environments (through engagement and education), without having to annoy the user with post-experience questionnaires. However, results suggest interaction in virtual heritage environments is so contextually embedded; subjective post-test questionnaires can still be more reliable than evaluating task performance. KeywordsPalenque–Virtual heritage–Cultural learning–Mayan
  Virtual Reality 05/2012;
• Article: Virtual reality as a communication process

  Daniele Marini, Raffaella Folgieri, Davide Gadia, Alessandro Rizzi
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  ABSTRACT: In this work, we consider immersive Virtual Reality (VR) as a communication process between humans, mediated by computer systems, which uses interaction, visualization, and other sensory stimuli to convey information. From this viewpoint, it is relevant to understand how VR can solve a given communication problem, what is therefore the expressive power of VR system, i.e., its ability in establishing the communication, what are the guidelines to design an effective system, and what are the more relevant models of VR applications. Firstly, we try to clarify the notion of reality in Virtual Reality systems and conclude that reality is not an intrinsic characteristic of VR, rather the result of a conventional way of coding information. The purpose of coding is to lead the observer to the conclusion that the VR set is what is called in italian as verisimile (from Latin veri similis), i.e., “similar-to-the-real-thing”. So the creation of an effective VR application is an artifice or an illusion. But in order to avoid an over-reliance on the creativity of the VR designer, we intend to identify a solid ground on which different kinds of VR solutions can be considered in terms of their ability to solve the desired communication objective. To this aim, we will rely on methods derived from rhetoric to semiotics. KeywordsVirtual Reality–Semiotics–Communication–Realism
  Virtual Reality 05/2012;
• Article: Grasp programming by demonstration in virtual reality with automatic environment reconstruction

  Jacopo Aleotti, Stefano Caselli
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  ABSTRACT: A virtual reality system enabling high-level programming of robot grasps is described. The system is designed to support programming by demonstration (PbD), an approach aimed at simplifying robot programming and empowering even unexperienced users with the ability to easily transfer knowledge to a robotic system. Programming robot grasps from human demonstrations requires an analysis phase, comprising learning and classification of human grasps, as well as a synthesis phase, where an appropriate human-demonstrated grasp is imitated and adapted to a specific robotic device and object to be grasped. The virtual reality system described in this paper supports both phases, thereby enabling end-to-end imitation-based programming of robot grasps. Moreover, as in the PbD approach robot environment interactions are no longer explicitly programmed, the system includes a method for automatic environment reconstruction that relieves the designer from manually editing the pose of the objects in the scene and enables intelligent manipulation. A workspace modeling technique based on monocular vision and computation of edge-face graphs is proposed. The modeling algorithm works in real time and supports registration of multiple views. Object recognition and workspace reconstruction features, along with grasp analysis and synthesis, have been tested in simulated tasks involving 3D user interaction and programming of assembly operations. Experiments reported in the paper assess the capabilities of the three main components of the system: the grasp recognizer, the vision-based environment modeling system, and the grasp synthesizer. KeywordsVirtual reality-Environment modeling-Grasp programming-Glove interaction
  Virtual Reality 04/2012;
• Article: Piavca: a framework for heterogeneous interactions with virtual characters

  Marco Gillies, Xueni Pan, Mel Slater
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  ABSTRACT: This paper presents a virtual character animation system for real- time multimodal interaction in an immersive virtual reality setting. Human to human interaction is highly multimodal, involving features such as verbal language, tone of voice, facial expression, gestures and gaze. This multimodality means that, in order to simulate social interaction, our characters must be able to handle many different types of interaction and many different types of animation, simultaneously. Our system is based on a model of animation that represents different types of animations as instantiations of an abstract function representation. This makes it easy to combine different types of animation. It also encourages the creation of behavior out of basic building blocks, making it easy to create and configure new behaviors for novel situations. The model has been implemented in Piavca, an open source character animation system.
  Virtual Reality 04/2012; 14(4):221-228.
• Article: Multisensory VR exploration for computer fluid dynamics in the CoRSAIRe project

  J. M. Vézien, B. Ménélas, J. Nelson, L. Picinali, P. Bourdot, M. Ammi, B. F. G. Katz, J. M. Burkhardt, L. Pastur, F. Lusseyran
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  ABSTRACT: In the last 30years, the evolution of digital data processing in terms of processing power, storage capacity, and algorithmic efficiency in the simulation of physical phenomena has allowed the emergence of the discipline known as computational fluid dynamics or CFD. More recently, virtual reality (VR) systems have proven an interesting alternative to conventional user interfaces, in particular, when exploring complex and massive datasets, such as those encountered in scientific visualization applications. Unfortunately, all too often, VR technologies have proven unsatisfactory in providing a true added value compared to standard interfaces, mostly because insufficient attention was given to the activity and needs of the intended user audience. The present work focuses on the design of a multimodal VR environment dedicated to the analysis of non-stationary flows in CFD. Specifically, we report on the identification of relevant strategies of CFD exploration coupled to adapted VR data representation and interaction techniques. Three different contributions will be highlighted. First, we show how placing the CFD expert user at the heart of the system is accomplished through a formalized analysis of work activity and through system evaluation. Second, auditory outputs providing analysis of time-varying phenomena in a spatialized virtual environment are introduced and evaluated. Finally, specific haptic feedbacks are designed and evaluated to enhance classical visual data exploration of CFD simulations.
  Virtual Reality 04/2012; 13(4):257-271.
• Article: Interactive multi-modal suturing

  Shahram Payandeh, Fuhan Shi
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  ABSTRACT: We present a mechanics-based interactive multi-modal environment designed as part of a serious gaming platform. The specific objectives are to teach basic suturing and knotting techniques for simple skin or soft tissue wound closure. The pre-wound suturing target, skin, or deformable tissue is modeled as a modified mass-spring system. The suturing material is designed as a mechanics-based deformable linear object. Tools involved in a typical suturing procedures are also simulated. Collision management modules between the soft tissue and the needle, the soft tissue and the suture are analyzed. In addition to modeling the interactive environment of a typical suturing procedure, basics of the modeling approaches on the evaluation of a stitch formed by the user are also discussed. For example, if needle insertion points are too close from each other or to the edge of the wound, when the suture is pulled, the suture will tear the soft tissue instead of suturing the incision together. Experiment results show that our simulator can run on a standard personal computer and allow users to perform different suturing patterns with smooth graphics and haptic feedback. KeywordsVirtual suturing-Suture model-Wound closure-Tissue tearing-Haptic feedback-Surgical training environment-Serious games
  Virtual Reality 04/2012; 14(4):241-253.
• Article: Presence in the age of social networks: augmenting mediated environments with feedback on group activity

  Francesco Martino, Roberto Baù, Anna Spagnolli, Luciano Gamberini
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  ABSTRACT: The present study aimed at increasing behavioral engagement in groups of networked people by providing feedback on the group activity. Each participant logged into an on-line virtual environment for four subsequent treasure-hunting sessions along with other nine players. During the game, all players communicated dyadically through textual chats, and searched for the treasures in the virtual environment. In two conditions, the participants received a visual feedback depicting the communication activity with the group based on social network analysis indices (i.e. ‘centrality’ or ‘reciprocity’). Feedback was not provided in the third condition. The underlying assumption was that if the group activity becomes more visible to the individual user through the feedback, then the behavioral engagement with the group increases. The resulting behavioral engagement was measured with two techniques, one based on the amount of messages exchanged and one based on self-reported measures. The results show that feedback improved the exchange of messages with respect to the control condition and that this effect was only partially captured by self-reported measures.
  Virtual Reality 04/2012; 13(3):183-194.
• Article: Towards the development of a virtual environment-based training system for mechanical assembly operations

  John E. Brough, Maxim Schwartz, Satyandra K. Gupta, Davinder K. Anand, Robert Kavetsky, Ralph Pettersen
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  ABSTRACT: In this paper, we discuss the development of Virtual Training Studio (VTS), a virtual environment-based training system that allows training supervisors to create training instructions and allows trainees to learn assembly operations in a virtual environment. Our system is mainly focused on the cognitive side of training so that trainees can learn to recognize parts, remember assembly sequences, and correctly orient the parts during assembly operations. Our system enables users to train using the following three training modes: (1) Interactive Simulation, (2) 3D Animation, and (3) Video. Implementing these training modes required us to develop several new system features. This paper presents an overview of the VTS system and describes a few main features of the system. We also report user test results that show how people train using our system. The user test results indicate that the system is able to support a wide variety of training preferences and works well to support training for assembly operations.
  Virtual Reality 04/2012; 11(4):189-206.
• Source

  Available from: citeseerx.ist.psu.edu

  Article: Visual immersive haptic mathematics

  Alexei Sourin, Lei Wei
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  ABSTRACT: In the modern urban society, human brain is not being sufficiently trained to deal with problems which require 3D perception. As a result, when teaching subjects richly infused with mathematics it is usually a challenge for the learners to follow the instructor and visualize how mathematical concepts reflect in 3D geometry and colors. We have proposed an approach that would allow for defining complex geometry, visual appearance and tangible physical properties of the virtual objects using language of mathematical functions. It allows the learners to get immersed within the 3D scene and explore the shapes which are being modeled visually and haptically. We illustrate this concept using our function-based extension of X3D and VRML. Besides definition of objects with mathematical functions straight in the scene file, standard X3D and VRML objects can be converted to tangible ones as well as augmented with function-defined visual appearances. Since the function-defined models are small in size, it is possible to perform their collaborative interactive modifications with concurrent synchronous visualization at each client computer with any required level of detail.
  Virtual Reality 04/2012; 13(4):221-234.
• Source

  Available from: sis.pitt.edu

  Article: The Virtual Trillium Trail and the empirical effects of Freedom and Fidelity on discovery-based learning

  Maria C. R. Harrington
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  ABSTRACT: The Virtual Trillium Trail is a new kind of desktop virtual reality application that crosses over into the area of geospatial, educational simulations. Visual fidelity significantly impacts intrinsic learning, activity in situ, and knowledge gained, independent of other factors. The main empirical contribution of this report is on the impact of the user interface design parameters of graphical fidelity and navigational freedom on learning outcomes. A planned orthogonal contrast, Two-way ANOVA with the factors of Visual Fidelity and Navigational Freedom—both scaled, and set to high and low levels—shows significant impacts on the variables of Salient Events, a proxy for discovery-based learning, and Knowledge Gained, as measured between a pre-test and a post-test. Thus, there is strong empirical evidence to support the use of desktop virtual environments, built with high-fidelity, photo-realistic, and free navigational game engine technology, as educational simulations for informal education. The high-level Visual Fidelity combined with the high-level Navigational Freedom condition showed a mean learning gain of 37.44% and is significantly superior to the low-level Visual Fidelity, low-level Navigational Freedom condition, ceteris paribus. KeywordsVirtual reality–Serious games–Educational simulations–Child–computer–environment interface–Discovery-based learning–Ecology education–User interfaces–Three-dimensional graphics and realism
  Virtual Reality 04/2012;
• Source

  Available from: citeseerx.ist.psu.edu

  Article: Tangible props for scientific visualization: concept, requirements, application

  Krzysztof Jakub Kruszyński, Robert van Liere
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  ABSTRACT: In this paper, we explore the use of printed tangible props as input devices for scientific visualization. Three-dimensional printing technology is used to create a physical representation of data. The object is then used as a tangible input prop, which exactly matches the data. In addition, two-handed interaction with a stylus is performed on the prop without the use of buttons, instead relying on the detection of contact between the stylus and the prop through precise calibration and tracking. This allows the sense of touch to be harnessed to create a more efficient and natural interaction method for scientific visualizations in virtual and augmented reality. We explain the concept of tangible props and where it can be applied. We also consider the technical requirements of systems using such props. Finally, we present our example application, which uses printed tangible props for interactive measurement of marine coral data. The use of tangible props is found to improve the usability of the application.
  Virtual Reality 04/2012; 13(4):235-244.
• Source

  Available from: citeseerx.ist.psu.edu

  Article: M2S maps: supporting real-world navigation with mobile VR

  Xiaolong Zhang
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  ABSTRACT: Mobile devices are becoming increasingly integrated into our society. In addition to entertaining people with applications like pervasive games, mobile devices can also help to address cognitive challenges people face in the real world. This paper, by drawing on research findings from cognitive psychology and geography, explores a design to use mobile VR to help people overcome one cognitive barrier in navigation, which is to establish the correspondence between 2D spatial information found in maps and 3D entities they perceive from the real world. The design offers users multi-format, multi-scale, and semantic (M2S) maps, ranging from 2D maps to 3D immersive environments, and helps users to connect 2D maps to the real world through 3D environments which are equipped with semantic representation and animation techniques. Consequently, users can apply various kinds of spatial knowledge, 2D or 3D, in understanding the real world as well as assisting in navigation. This research enhances the design repertoire of mobile VR, and suggests a way to integrate virtual environments into people’s real-world life by examining the cognitive implications of 3D models on users’ activities.
  Virtual Reality 04/2012; 11(2):161-173.
• Source

  Available from: public.iastate.edu

  Article: Modeling and real-time simulation architectures for virtual prototyping of off-road vehicles

  Manoj Karkee, Brian L. Steward, Atul G. Kelkar, Zachary T. Kemp
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  ABSTRACT: Virtual Reality-based simulation technology has evolved as a useful design and analysis tool at an early stage in the design for evaluating performance of human-operated agricultural and construction machinery. Detecting anomalies in the design prior to building physical prototypes and expensive testing leads to significant cost savings. The efficacy of such simulation technology depends on how realistically the simulation mimics the real-life operation of the machinery. It is therefore necessary to achieve ‘real-time’ dynamic simulation of such machines with operator-in-the-loop functionality. Such simulation often leads to intensive computational burdens. A distributed architecture was developed for off-road vehicle dynamic models and 3D graphics visualization to distribute the overall computational load of the system across multiple computational platforms. Multi-rate model simulation was also used to simulate various system dynamics with different integration time steps, so that the computational power can be distributed more intelligently. This architecture consisted of three major components: a dynamic model simulator, a virtual reality simulator for 3D graphics, and an interface to the controller and input hardware devices. Several off-road vehicle dynamics models were developed with varying degrees of fidelity, as well as automatic guidance controller models and a controller area network interface to embedded controllers and user input devices. The simulation architecture reduced the computational load to an individual machine and increased the real-time simulation capability with complex off-road vehicle system models and controllers. This architecture provides an environment to test virtual prototypes of the vehicle systems in real-time and the opportunity to test the functionality of newly developed controller software and hardware. KeywordsReal-time simulation–Distributed architecture–Virtual reality–Vehicle dynamics models–Multi-rate simulation
  Virtual Reality 04/2012; 15(1):83-96.
• Source

  Available from: zhang.ist.psu.edu

  Article: Multiscale traveling: crossing the boundary between space and scale

  Xiaolong (Luke) Zhang
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  ABSTRACT: Adding multiscale interaction capabilities to 3D virtual environments may permit work with huge virtual worlds that might otherwise be too large to manage. Multiscale technology has shown potential to support user interactions. This paper reports an experimental study of two multiscale traveling techniques. Our results show that while allowing a flexible control on travel speed and accuracy is beneficial, directly traversing the space-scale could be a challenge for users, probably due to difficulties in perceiving scalable virtual space and executing scaling operations. The results suggest that more research is needed to improve the understanding of the coupling of space and scale in multiscale user interface and to harness the full potentials of multiscale traveling techniques.
  Virtual Reality 04/2012; 13(2):101-115.
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  Available from: citeseerx.ist.psu.edu

  Article: Analysis of expression in simple musical gestures to enhance audio in interfaces

  Luca Mion, Gianluca D’Incà
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  ABSTRACT: Expression could play a key role in the audio rendering of virtual reality applications. Its understanding is an ambitious issue in the scientific environment, and several studies have investigated the analysis techniques to detect expression in music performances. The knowledge coming from these analyses is widely applicable: embedding expression on audio interfaces can drive to attractive solutions to emphasize interfaces in mixed-reality environments. Synthesized expressive sounds can be combined with real stimuli to experience augmented reality, and they can be used in multi-sensory stimulations to provide the sensation of first-person experience in virtual expressive environments. In this work we focus on the expression of violin and flute performances, with reference to sensorial and affective domains. By means of selected audio features, we draw a set of parameters describing performers’ strategies which are suitable both for tuning expressive synthesis instruments and enhancing audio in human–computer interfaces.
  Virtual Reality 04/2012; 10(1):62-70.