Objectivité et emploi de la couleur dans les images scientifiques

International audienceRéflexion sur le statut de l'emploi de la couleur dans les images scientifique

Integration and evaluation of haptic feedbacks: From CAD models to virtual prototyping

International audienceThis paper studies the benefits that haptic feedback can provide in performing complex maintenance tasks using virtual mock-ups. We have carried out user study that consisted on two experiments where participants had to perform an accessibility task. A human-scale string-based haptic interface was used to provide the operator with haptic stimuli. A prop was used to provide grasp feedback. A mocap system tracks user's hand and head movements while a 5DT data-glove is used to measure finger flexion. In the first experiment the effect of haptic (collision) and visual feedback are investigated. In the second experiment we investigated the effect of haptic guidance on operator performance. The results were analyzed in terms of task completion time and collision avoidance. Experiments show that haptic stimuli proved to be more efficient than visual ones. In addition, haptic guidance helped the operators to correct trajectories and hence improve their performance

Natural interface for interactive virtual assembly in augmented reality using Leap Motion Controller

In this paper, an augmented reality methodology based on the use of a low-invasiveness hand tracking device is presented. The developed methodology, allows the user to be visually immersed into an augmented scene by means of a head-mounted display. He can interact with the virtual objects without any wearable sensor using the Leap Motion Controller that is able to acquire the pose of each finger of both hands by optical triangulation without markers. In this way, the interaction between the user and the scene can be considered “natural”. The interaction between hands and objects and the assembling among objects is achieved by the modification of the Object Active Feature–Grasping Active Feature methodology, based on the use of algebraic kinematic constraint equations. The approach has been adapted to take into account the specific information coming from the tracking device. An example of implementation is reported and an experimental usability study discussed