Effect of stiffness on tapping performance. Do you rely on force to keep synchronised along with a metronome?

International audienceSeveral works have examined the robustness of the sound-action loop to auditory delay, and the effects of delay on performance. In this paper we propose a complementary approach, by modifying the stiffness of the tapped object. Participants had to perform synchronous tapping along with a metronome reference, using a one degree-of-freedom haptic device. Two experimental conditions were tested: with and without sound from the tapped object. Dynamics of the experiment were recorded in order to have a closer look at the dynamic factors affecting performance. Results show that the increase of the stiffness of the tapped object leaded to a decrease of the asynchrony, indicating that the modification of the force dynamics has an effect on performance. On the basis of this observation, an explanation of the negative asynchrony effect is proposed. At last, we show that sound feedback improves performance only when the stiffness is very low

Being There & Being With: The Philosophical and Cognitive Notions of Presence and Embodiment in Virtual Instruments

International audienceIn this paper, we will discuss two main concepts, associated with the development of Virtual Worlds, which are "Presence" and "Embodiment". Presence is stamped as the sense of "Being there", that has to be reconstructed in Local world to render Distant Worlds accessible by net-worked or mediated communications. "Embodiment" could be the property of a Virtual entity to be incorporated by human as a second nature. We will show then, how (1) the first situation can be seen as a definition of "immateriality" and its correlative concept of infinity, (2) the second situation can be seen as a definition of "tangibility" with its correlative concept of instrumental embodiment. After exploring the complementary properties of these situations in detail, we will focus on the second one, identified as "the instrumental situation". We will propose some of its relevant properties, those that are able to trigger the sense of embodiment, as the main property supported in the real physical world by the feature of "tangibility". Consequently, we estimate that "embodiment" is more important than the tangibility in itself and we examine some criteria able to help us to recreate them in digital representations

Technologies de la Simulation Interactive de Modèles Physiques Multisensoriels

This thesis presents my research activity on multisensory interactive simulation (gesture, sound and image), in technological and conceptual aspects. This interdisciplinary research concerns three fields : 1/ physical modeling for simulation, 2/ hardware and software architectures for real time computation, 3/ interactive gestural interfaces (with force feedback). Work done in these three fields is presented chronologically.Ce mémoire présente mon activité de recherche sur la simulation interactive multisensorielle (geste, son et image), dans ses aspects technologiques et conceptuels. C’est une recherche interdisciplinaire qui concerne trois domaines : 1/ modélisation physique pour la simulation, 2/ architectures matérielles et logicielles pour le calcul temps réel, 3/ interfaces gestuelles interactives (à « retour d’effort »). Les travaux effectués dans ces trois domaines sont exposés de manière chronologique