Ijodir 2011 / Vol.6 - n°1

Validity evaluation of a spatial memory task in virtual environments

Last Updated on Thursday, 06 October 2011 17:00

Authors: S. T. Koenig1,2, G. P. Crucian3, A. Dünser1, C. Bartneck1, J. C. Dalrymple-Alford2

Institutions: 1Human Interface Technology Laboratory, Christchurch (New Zealand), 2University of Canterbury (New Zealand), 3William Beaumont Army Medical Center, El Paso (USA)

 

Abstract: A broad range of neuropsychological tests and trainings are used to assess cognitive function during rehabilitation after brain injury. However, given the everyday problems that patients struggle with, questions of ecological validity arise. For example, abstract tasks have little meaning to patients and decrease motivation to practice skills frequently. This study proposes a spatial memory task with high ecological validity that can be integrated into any virtual environment. Environments and target objects can be individually designed for each user to provide a relevant context and high motivation for patients with cognitive deficits. The task has been evaluated with both brain-injured and healthy individuals. 45 participants completed the virtual task and a battery of neuropsychological tests. Strong associations have been found with established tests of visual short-term memory. Due to high variability of test scores, no significant relationship with tests of spatial abilities has been established. High ecological validity of the spatial memory task caused five patients to show awareness of their cognitive deficits. Clinical implications and future task development are discussed.

Keywords: virtual environment, neuropsychology, rehabilitation, ecological validity, brain injury, spatial memory, validity evaluation.

 

Cutting the Cord: Wireless Mixed Reality Displays

Last Updated on Thursday, 06 October 2011 16:44

Authors: M. Csisinko, H. Kaufmann

Institution: University of Technology, Vienna (Austria)

 

Abstract: In this paper we present wireless technologies that can be used to transmit uncompressed stereoscopic video signals to wireless displays in real time. We introduce two output devices, a stereoscopic head mounted display (HMD) and a TFT display module. Both of them have been adapted to act as receivers in order to display wirelessly streamed Mixed Reality (MR) content. By way of example two educational MR applications are presented which were used for demonstration and testing purposes. A number of teaching scenarios are described where teachers and students greatly benefit from the use of wireless displays. We briefly summarize the results of our observations while developing and evaluating these displays.

Keywords: wireless display, wireless HMD.

 

Experience of a cloud-avatar: scientific challenges and artistic perspectives

Last Updated on Thursday, 06 October 2011 16:40

Authors: N. Delprat1,2, C. Leroux3, S. Fdili Alaoui1,4

Institutions: 1LIMSI-CNRS, Orsay (France), 2Université Pierre et Marie Curie, Paris (France), 3ESIEA, Paris (France), 4IRCAM Centre Pompidou, Paris (France)

 

Abstract: This paper presents the design and the implementation of an interactive simulation device for the virtual experience of an evanescent matter. The current prototype is based on a motion capture system and a particle generator for the graphics rendering. It allows for the investigation of various kinds of interactions with an avatar that represents in real time the user’s body in the form of a cloud. Questions such as perceptual limits of body recognition and relationships between the avatar material properties and the user’s action have been examined. The cognitive implications of this embodied virtual materiality provide many opportunities for creative work and research that will be discussed through an art-science approach.

Keywords: interactive simulation, virtual materiality, body-space relationship, art-science approach, phenomenology, virtual arts.

 

Designing for the Ubiquitous Computing era: towards the reinvention of everyday objects for rich services’ experiences

Last Updated on Thursday, 06 October 2011 16:31

Authors: P. Thébault1,2, H. Samier2, D. Bihanic3, S. Richir2

Institutions: 1Alcatel-Lucent Bell Labs, Nozay (France), 2Arts et Métiers ParisTech, Angers (France)

 

Abstract: Researchers of the Ubiquitous Computing community (Ubicomp) have been pursuing the vision of a world where technologies and services permeates every object of our lives for years. With components getting smaller, cheaper and more powerful, it has become possible to manufacture connected objects capable of interacting with resources of the World Wide Web. This opens up the possibility for researchers and practitioners to consider information as a design material and objects as platforms for services. By allowing users to personalize, complement or repurpose the functions of their objects, such services have a great impact on the way artifacts are designed. Designing for the Ubiquitous Era requires modifying our practice and reinforcing collaboration between disciplines at every steps of the creation process. In this article, we discuss the need to reinvent objects and to investigate the tools supporting the creation of rich services’ experiences.

Keywords: ubiquitous computing, design research, interaction design, product design, user experience design, connected objects, smart objects, object-based services, web of things.

 

Pulsed LED-LCD Multi-View System

Last Updated on Thursday, 06 October 2011 16:22

Authors: A. Pross, R. Blach, M. Bues, R. Reichel, O. Stefani

Institution: Fraunhofer IAO, Stuttgart (Germany)

 

Abstract: In this paper we present a multi-view stereo display concept based on pulsed LED light sources of a 3 LED/3 LCD projector. Switching LED sources allows high frequency shuttering of the displayed image and can therefore be used for multi-view systems. We have implemented a two user system which can be extended to more views with little expenditure. This alleviates the known principal problems of shutter-based multi-view systems of energy inefficiency, brightness degradation due to the projector shutter, and increasing crosstalk with the number of views.

Keywords: multi user system, multi view display system, virtual reality, stereoscopic display, immersive projection.

 

Hierarchical Puppetry: From Ragdoll Physics to Avatar Expression

Last Updated on Thursday, 06 October 2011 16:18

Author: J. Ventrella

Institution: Independant researcher, San Francisco (USA)

 

Abstract: This paper explores spontaneous avatar nonverbal expression, and addresses a problem of puppeteering: directly manipulating one’s avatar using mouse or touch input. Given typically sparse inputs to a virtual world, what is needed is a hierarchical scheme, whereby some avatar behaviors can be automated while the user manipulates higher level expressions. As an example of a rudimentary puppeteering scheme, the Physical Avatar is described, developed by the author for Second Life. The technical aspects of this system are put in the context of the more general problem of puppeteering. The brain’s control of body motion (especially expression) is considered as a natural system that can inspire solutions to the avatar puppeteering problem.

Keywords: avatar, expression, puppetry, ragdoll physics, direct-manipulation, homunculus, user interaction, second Life, virtual world.

 

Composing for the Interactive Medium

Last Updated on Thursday, 06 October 2011 16:18

Authors: R. Taylor1, G. Schofield2, J. Shearer2, J. Wallace2, P. Wright2, P. Boulanger1, P. Olivier2

Institutions: 1University of Alberta, Edmonton (Canada), 2Newcastle University (UK)

 

Abstract: We present a discussion of the role of the composer when developing content for the interactive, participatory medium. We describe compositional tensions which emerged during the creation and enactment of our interactive performance, humanaquarium, and discuss how the intertwined nature of interactive and aesthetic concerns inspired our creative innovation in the composition process.

Keywords: participatory performance, interactive art, composition, musicianship, experience-centered design.

 

Generate virtual worlds to explore data

Last Updated on Thursday, 06 October 2011 14:55

Author: D. Sebastien

Institution: Université de la Réunion (France)

 

Abstract: The quantity and variety of data stored in Information Systems (IS) make their analysis by experts and accessibility to non-specialist difficult. As immersive representations in 3D virtual worlds, also known as metaverses, offer new ways of displaying information, it is useful to transpose the data stored in IS into a metaverse. This paper introduces the basics to create a meta-model of architecture describing the structure of virtual worlds. Then we present two models instantiated from this meta-model. The Realistic Architecture Model focuses on the reproduction of natural environments whereas the Arborescent Architecture Model tries to be compatible with all IS architectures. Finally, as the data in Information Systems are regularly updated, we propose two methodologies to automate the generation of metaverses associated to the two models of architecture presented.

Keywords: model of metaverse, virtual worlds generation, immersive environments, Information Systems, meta-model, realistic architecture model, arborescent architecture model