Beyond the Tunnels: Advanced 3D graphical modulation

International audienceTunnels are 3D graphical sliders which modify the appearance of, or "modulate", one or several 3D objects simultaneously using these objects as cursors themselves. They rely on a strong visual feedback to provide multiple scales and parameters combinations which makes them appropriate for the use in immersive virtual musical instruments. In this paper we present applications of the Tunnels for collaborative modulation tasks, for avatars and weapons modifications in 3D video games, and for the control of interactive scenarios. We also propose several improvements to the Tunnels such as a method for storing them and a two-dimensional version called Grids

MACBETH: management of avatar conflict by employment of a technique hybrid

Since virtual objects do not prevent users from penetrating them, a virtual environment user may place his real hand inside a virtual object. If the virtual environment system prevents the user's hand avatar from penetrating the object, the hand avatar must be placed somewhere other than the user's real hand position. I propose a technique, named MACBETH (Management of Avatar Conflict By Employment of a Technique Hybrid) for managing the position of a user's hand avatar in a natural manner after it has been separated from the user's real hand due to collision with a virtual object. This technique balances visual/proprioceptive discrepancy in position and velocity by choosing each so that they are equally detectable. To gather the necessary information to implement MACBETH, I performed user studies to determine users' detection thresholds for visual/proprioceptive discrepancy in hand position and velocity. I then ran a user study to evaluate MACBETH against two other techniques for managing the hand avatar position: the rubber-band and incremental-motion techniques. Users rated MACBETH as more natural than the other techniques and preferred MACBETH over both. Users performed better on a hand navigation task with MACBETH than with the incremental-motion technique and performed equally well as with the rubber-band technique

The Effect of 3D Widget Representation and Simulated Surface Constraints on Interaction in Virtual Environments

This paper reports empirical results from two studies of effective user interaction in immersive virtual environments. The use of 2D interaction techniques in 3D environments has received increased attention recently. We introduce two new concepts to the previous techniques: the use of 3D widget representations; and the imposition of simulated surface constraints. The studies were identical in terms of treatments, but differed in the tasks performed by subjects. In both studies, we compared the use of two-dimensional (2D) versus threedimensional (3D) interface widget representations, as well as the effect of imposing simulated surface constraints on precise manipulation tasks. The first study entailed a drag-and-drop task, while the second study looked at a slider-bar task. We empirically show that using 3D widget representations can have mixed results on user performance. Furthermore, we show that simulated surface constraints can improve user performance on typical interaction tasks in the absence of a physical manipulation surface. Finally, based on these results, we make some recommendations to aid interface designers in constructing effective interfaces for virtual environments

Redirected Touching

In immersive virtual environments, virtual objects cannot be touched. One solution is to use passive haptics - physical props to which virtual objects are registered. The result is compelling; when a user reaches out with a virtual hand to touch a virtual object, her real hand touches and feels a real object. However, for every virtual object to be touched, there must be an analogous physical prop. In the limit, an entire real-world infrastructure would need to be built and changed whenever a virtual scene is changed. Virtual objects and passive haptics have historically been mapped one-to-one. I demonstrate that the mapping need not be one-to-one. One can make a single passive real object provide useful haptic feedback for many virtual objects by exploiting human perception. I developed and investigated three categories of such techniques: 1. Move the virtual world to align different virtual objects in turn with the same real object 2. Move a virtual object into alignment with a real object 3. Map real hand motion to different virtual hand motion, e.g., when the real hand traces a real object, the virtual hand traces a differently shaped virtual object. The first two techniques were investigated for feasibility, and the third was explored more deeply. The first technique (Redirected Passive Haptics) enables users to touch multiple instances of a virtual object, with haptic feedback provided by a single real object. The second technique (The Haptic Hand) attaches a larger-than-hand virtual user interface to the non-dominant hand, mapping the currently relevant part of the interface onto the palm. The third technique (Redirected Touching) warps virtual space to map many differently shaped virtual objects onto a single real object, introducing a discrepancy between real and virtual hand motions. Two studies investigated the technique's effect on task performance and its potential for use in aircraft cockpit procedures training. Users adapt rather quickly to real-virtual discrepancy, and after adaptation, users perform no worse with discrepant virtual objects than with one-to-one virtual objects. Redirected Touching shows promise for training and entertainment applications.Doctor of Philosoph

Étude de performance des interfaces humain-machine à base de métaphores visuelles pour les systèmes de réalité virtuelle

Les interfaces humain- machine dans le domaine des environnements virtuels -- Concepts de design et d'évaluation -- Manipulation des panneaux de dialogue à l'intérieur d'un environnement virtuel -- Manipulation des éléments d'interface virtuels d'un panneau de dialogue -- Interactions avec des menus flottant dans un contexte d'application RV concrète -- Conclusion et avenues de recherche futures