Etude preliminaire visant la determination de seuils de confort pour un zoom haptique

摘要

In order to resolve PDA display problems, we validated, in a previous study, the efficiency of a new zooming technique associated with a tactile feedback (haptic zoom). The displayed objects on a PDA screen being relatively small, it appears essential, in the present study, to define minimal and maximal comfort thresholds to ease gesture execution that correspond to zoom-in and zoom-out thresholds of the haptic zoom. The results of the experiment undertaken with a sensory substitution device show that:i) the choice of an object size close to 4 cm significantly increases the recognition rate, ii) minimal and maximal comfort thresholds, defined by a ratio C (see text), seem to be respectively at values of C =0.2 and 0.4, iii)strategies used by subjects prove to be productive if they agree with the requested task (estimate figure size and orientation) and the explored shape topography.