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Despite non-co-location, haptic stimulation at the wrist can potentially provide feedback regarding interactions at the fingertips without encumbering the user’s hand. Here we investigate how two types of skin deformation at the wrist (normal and shear) relate to the perception of the mechanical properties of virtual objects. We hypothesized that a congruent mapping (i.e. when the most relevant interaction forces during a virtual interaction spatially match the haptic feedback at the wrist) would result in better perception than other map- pings.We performed an experiment where haptic devices at the wrist rendered either normal or shear feedback during manipulation of virtual objects with varying stiffness, mass, or friction properties. Perception of mechanical properties was more accurate with congruent skin stimulation than noncongruent. In addition, discrimination performance and subjective reports were positively influenced by congruence. This study demonstrates that users can perceive mechanical properties via haptic feedback provided at the wrist with a consistent mapping between haptic feedback and interaction forces at the fingertips, regardless of congruence. 

Detailed hand motions play an important role in face-to-face communication to emphasize points, describe objects, clarify concepts, or replace words altogether. While shared virtual reality (VR) spaces are becoming more popular, these spaces do not, in most cases, capture and display accurate hand motions. In this paper, we investigate the consequences of such errors in hand and finger motions on comprehension, character perception, social presence, and user comfort. We conduct three perceptual experiments where participants guess words and movie titles based on motion captured movements. We introduce errors and alterations to the hand movements and apply techniques to synthesize or correct hand motions. We collect data from more than 1000 Amazon Mechanical Turk participants in two large experiments, and conduct a third experiment in VR. As results might differ depending on the virtual character used, we investigate all effects on two virtual characters of different levels of realism. We furthermore investigate the effects of clip length in our experiments. Amongst other results, we show that the absence of finger motion significantly reduces comprehension and negatively affects people’s perception of a virtual character and their social presence. Adding some hand motions, even random ones, does attenuate some of these effects when it comes to the perception of the virtual character or social presence, but it does not necessarily improve comprehension. Slightly inaccurate or erroneous hand motions are sufficient to achieve the same level of comprehension as with accurate hand motions. They might however still affect the viewers’ impression of a character. Finally, jittering hand motions should be avoided as they significantly decrease user comfort.