Comparing different Visuo-Haptic environments for vitual prototyping applications

The use of haptic devices in Virtual Reality applicationsmakes the interaction with the digital objects easier, byinvolving the sense of touch in the simulation. The mostwidespread devices are stylus-based, so the user interacts withthe virtual world via either a tool or a stylus. These kinds ofdevices have been effectively used in several virtual prototypingapplications, in order to allow the users to easily interact withthe digital model of a product. Among the several open issuesrelated to these applications, there is the choice of the set-upand of the techniques adopted to combine the visual and thehaptic stimuli.This paper presents the comparison of three differentsolutions specifically studied for virtual prototypingapplications and in particular for usability assessment. Thefirst is a simple desktop configuration where the user looks at ascreen, and visual and haptic stimuli are presented in a delocatedmanner. The second is a HMD based set-up where theuser has a more natural first-person immersive interaction. Thethird requires a video-see-trough HMD in order to augment thevirtual scene with the visualization of the real user’s hand.The test realized with the users on these three different setupshave been finalized to study the effect of two differentfactors that are crucial for the effectiveness and the userfriendlinessof the interaction. One is the perception of thevisual and haptic stimuli in a collocated manner; the other isthe visualization of his/her own hand during the interactionwith the virtual product.