Browsing through 3D representations of unstructured picture collections: an empirical study

The paper presents a 3D interactive representation of fairly large picture collections which facilitates browsing through unstructured sets of icons or pictures. Implementation of this representation implies choosing between two visualization strategies: users may either manipulate the view (OV) or be immersed in it (IV). The paper first presents this representation, then describes an empirical study (17 participants) aimed at assessing the utility and usability of each view. Subjective judgements in questionnaires and debriefings were varied: 7 participants preferred the IV view, 4 the OV one, and 6 could not choose between the two. Visual acuity and visual exploration strategies seem to have exerted a greater influence on participants' preferences than task performance or feeling of immersion.Comment: 4 page

La recherche pour l'utilisation durable des ressources minérales

L'utilisation éco-efficace des matières premières minérales non renouvelables est l'une des conditions du développement durable. Au moment de Rio+20, le défi reste considérable. La recherche est nécessaire au développement de l'économie circulaire et pour trouver des solutions afin de produire - avec moins d'eau, d'énergie et de déchet - les ressources primaires dont le monde aura besoin au cours des prochaines décennies. Cet article présente une introduction à la recherche française et européenne actuellement déployée dans le domaine des matières premières minérales

A seamless solution for 3D real-time interaction: design and evaluation

This paper aims to propose and evaluate a markerless solution for capturing hand movements in real time to allow 3D interactions in virtual environments (VEs). Tools such as keyboard and mice are not enough for interacting in 3D VE; current motion capture systems are expensive and require wearing equipment. We developed a solution to allow more natural interactions with objects and VE for navigation and manipulation tasks. We conducted an experimental study involving 20 participants. The goal was to realize object manipulation (moving, orientation, scaling) and navigation tasks in VE. We compared our solution (Microsoft Kinect-based) with data gloves and magnetic sensors (3DGloves) regarding two criteria: performance and acceptability. Results demonstrate similar performance (precision, execution time) but a better overall acceptability for our solution. Preferences of participants are mostly in favor of the 3DCam, mainly for the criteria of comfort, freedom of movement, and handiness. Our solution can be considered as a real alternative to conventional systems for object manipulation in virtual reality

ERA-MIN Research Agenda

European Research Area - Network on the Industrial Handling of Raw Materials for European Industriesroadmap of the "ERA-MIN" eranetNon-energy and non-agricultural raw materials underpin the global economy and our quality of life. They are vital for the EU's economy and for the development of environmentally friendly technologies essential to European industries. However, the EU is highly dependent on imports, and securing supplies has therefore become crucial. A sustainable supply of mineral products and metals for European industry requires a more efficient and rational consumption, enhanced substitution and improved recycling. Recycling from scrap to raw materials has been rapidly gaining in quantity and efficiency over the last years. However, continuous re-use cannot provide alone the necessary quantities of mineral raw materials, due to i) recycling losses, ii) the worldwide growing demand in raw materials, and iii) the need of "new" elements for the industry. To fully meet future needs, metals and mineral products from primary sources will still be needed in the future. Most of them will continue to be imported from sources outside Europe; but others can, and should, be produced domestically. Advanced research and innovation are required to improve the capacity of existing technologies to discover new deposits, to improve the efficiency of the entire geomaterials life cycle from mineral extraction to the use as secondary resource of products at the end of their industrial life, and to reduce the environmental footprint of raw materials extraction and use. Research and innovation must be made to acquire knowledge as well, and to improve our basic understanding of all engineering and natural processes involved in the raw materials life cycle, as well as the coupling of these processes. Finally, research has to go beyond the present-day economic and technological constraints, and it should be closely associated with training and education in order to maintain existing skills and to share the most recent developments with the industrial sector. A long-term vision of research is necessary in order to have the capacity of evaluating the environmental and societal impacts of present and developing industrial activities and to imagine tomorrow's breakthrough concepts and technologies that will create new industrial opportunities. These objectives require the input of contrasted scientific and technical skills and competences (earth science, material science and technology, chemistry, physics, engineer, biology, engineering, environmental science, economy, social and human sciences, etc). An important challenge is to gather all these domains of expertise towards the same objective. The ERA-MIN Research Agenda aims at listing the most important topics of research and innovation that will contribute to i) secure the sustainable supply and management of non-energy and non-agricultural raw materials, and ii) offer opportunities of investment and employment opportunities in the EU

Processus d'induction d'émotions dans les environnements virtuels et le jeu vidéo

Les domaines de la réalité virtuelle et du jeu vidéo convoquent les problématiques émotionnelles dans leurs objectifs respectifs de présence et de flow zone. Cependant, la question des méthodologies d'induction d'émotions dans les environnements virtuels de ces médiums n'a pas été largement questionnée. Après avoir défini ce que sont les émotions dans la littérature philosophique, psychologiste et physiologiste, nous cherchons à montrer les liens supposés existants entre l'émotion et les états extatiques de présence en réalité virtuelle et de flow zone dans les jeux vidéo. Nous commençons donc par montrer combien le niveau de connaissance des médiums peut influencer la sensibilité aux inductions d'émotions dans les environnements virtuels. Puis nous mettons en place une stratégie inductive d'émotions basée sur une gestion itérative des niveaux de challenge en lien avec les niveaux de compétences acquises.Nous avons validé au travers de deux expériences empiriques ayant impliquées 176 participants, une méthodologie d'induction d'émotions basée sur un schéma circomplexe. Ce schéma, construit autour de la valence et le niveau d'activation des émotions, permet d'induire des émotions dans les cinq composantes essentielles de la conception d'environnements virtuels pour la réalité virtuelle ou les jeux vidéo : la chromatique, la luminosité, la vitesse des mouvements, la dimension des espaces et le volume des interactions sociales.Mots clés : réalité virtuelle, jeu vidéo, émotions, présence, flow zone.The fields of virtual reality and video games summon the emotional issues in their respective goals of presence and flow area. However the question of methodologies for inducing emotions in virtual environments in these mediums has not yet been widely questioned. After defining what emotions are in the philosophical, as in psychologist and physiologist literature, we seek to show existing links between emotion and states of presence in virtual reality and flow zone in video games. We show how the level of knowledge of the mediums may influence susceptibility to induction of emotions in virtual environments. Then we define a way of inducing emotions based on an iterative level management challenge in relation to the skill level.We validated through two empirical experiments that involved 176 participants a methodology for inducing emotions based on a circumplex pattern. This scheme built around the valence and arousal level of emotion, able to induce emotions in the five essential items component of the design of virtual environments for virtual reality and video games: color, brightness, movement speed, size of the space, and the volume of social interactions.Keywords: virtual reality, video games, emotions, presence, flow area.PARIS-Arts et Métiers (751132303) / SudocSudocFranceF

De la présence à l’incarnation: proposition d’un méta-modèle pour la réalité virtuelle

Les sentiments de présence et d’incarnation sont deux dimensions centrales de l’expérience utilisateur en environnement virtuel immersif. Suite à une revue de littérature portant sur ces deux concepts, nous en proposons une articulation théorique au sein d’un méta-modèle « Présence – Incarnation ». L’introduction de ce modèle aboutit à la proposition d’un questionnaire permettant l’évaluation subjective des sentiments de présence et d’incarnation d’utilisateurs immergés dans une application de réalité virtuelle. Les implications méthodologiques de ce modèle et ses perspectives applicatives sont ensuite évoquées afin d’introduire la ligne directrice de nos travaux futurs

REC: A Unity Tool to Replay, Export and Capture Tracked Movements for 3D and Virtual Reality Applications

We present REC, a Unity open-source tool for developers and researchers to record, export and replay the movements of virtual reality users and virtual characters. Recording both real-time body tracking and animations, this tool makes it possible to export skeletal data in a comma-separated values (CSV) file allowing to process and analyze users' movements. We also provide a feature to reload and replay saved movements directly from the CSV file on virtual characters in a 3D environment

Support optimization for additive manufacturing: application to FDM

Purpose This paper aims to present a new methodology to optimize the support generation within the FDM process. Design/methodology/approach Different methods of support generation exist, but they are limited with regards to complex parts. This paper proposes a method dedicated to support generation, integrated into CAD software. The objective is to minimize the volume of support and its impact on a part’s surface finish. Two case studies illustrate the methodology. The support generation is based on an octree’s discretization of the part. Findings The method represents a first solid step in the support optimization for a reasonable calculation time. It has the advantage of being virtually automatic. The only tasks to be performed by the designer are to place the part to be studied with respect to the CAD reference and to give the ratio between the desired support volume and the maximum volume of support. Research limitations/implications In the case studies, a low gain in manufacturing time was observed. This is explained by the honeycomb structure of the support generated by a common slicing software whilst the proposed method uses a “full” structure. It would be interesting to study the feasibility of an optimized support, with a honeycomb structure but with a preservation of the surface which is in contact with the part. Originality/value This solution best fits the needs of the designer and manufacturer already taking advantage of existing solutions. It is adaptable to any part if the withdrawal of support is taken into account. It also allows the designer to validate the generation of support throughout the CAD without breaking the digital chain

Quantitative and Qualitative Exploration of the Effect of a Wearable Item on Non-Organic Virtual Limb Embodiment and User Behavior in Immersive Environments

This experiment was designed to investigate the potential contribution to the sense of embodiment of a wristband worn by the participants in both real and virtual environments. In addition, two virtual limb models were compared following a mixed between-within subjects design: an organic hand and a non-organic prosthesis matching the proposed task. Quantitative results revealed no significant effect of the wristband, while post-experiment semistructured interviews revealed that the wristband fostered the identification with the virtual limbs for several participants, but that it might be conditioned by interindividual differences. Ownership scores were significantly higher with the virtual hand. However, participants experienced a very high sense of agency with both conditions despite the lack of finger tracking when controlling the prosthesis. Agency was positively correlated with participants' perceived change in their body schema when embodying the prosthesis. Subjective and objective measures demonstrated that participants were less hesitant and that more collisions were recorded at higher speeds against potentially threatening objects with the non-organic prosthesis

A design methodology for parts using additive manufacturing

Additive Manufacturing (AM) allows designer to sidestep several design requirements and to create free forms, hollow parts or direct assemblies. This process also allows direct recycling of plastic into new parts, which eases the raw material supply. However, although several methodologies are used to redes-ign products and parts, none is dedicated to a real design of parts and products in AM. At first, we will sug-gest the base of a new design methodology for an end-user who wants to create a product or a part in AM. Then, we will show an example of using our methodology. Finally, we will conclude on the limits of this methodology and on our next work to validate our methodology