Investigating how user avatar in touchless interfaces affects perceived cognitive load and two-handed interactions

Abstract

In recent years, touchless-enabling technologies have been more and more adopted for providing public displays with gestural interactivity. This has led to the need for novel visual interfaces aimed at solving issues such as communicating interactivity to users, as well as supporting immediate usability and "natural" interactions. In this paper, we focus our investigation on a visual interface based only on the use of in-air direct manipulations. Our study aims at evaluating whether and how the presence of an Avatar that replays user's movements may decrease the perceived cognitive workload during interactions. Moreover, we conducted a brief evaluation of the relationship between the presence of the Avatar and the use of one or two hands during the interactions. To this end, we compared two versions of the same interface, differing only for the presence/absence of the user's Avatar. Our results showed that the Avatar contributes to lower the perceived cognitive workload during the interactions.

Child-display interaction

“…For instance, Müller et al showed that interactivity can be recognized after less than three seconds using avatars [23]; however, their work considers users of various ages, without an in-depth analysis of children's behaviors. Similar limitations can be found in [8,17,18,33]. In the context of child-computer interaction, other facets of touchless gestural interaction have been investigated, mainly in order to understand the effect of such novel paradigm in learning activities [1,5,26], but also for gaming purposes [4,5,12].…”

“…the inability to understand the interaction modality of the display [8]). Gentile et al showed also that the presence of an avatar makes two-handed interactions more "natural" in the sense that it contributes to a reduction of the cognitive workload while interacting with public displays [17]. However, to the best of our knowledge, prior work has not focused on the use of avatar-based solutions by a specific class of users, such as children.…”

“…Tiles can be dragged and dropped by driving the avatar's hands on top of them with users' own hands, and by closing (grab), moving (drag) and opening (drop) the hands correspondingly. As explained in section 2.1, the presence of the avatar allows for more natural interactions [17] and should facilitate users in understanding how to interact with the system, thus addressing the affordance blindness [23].…”

Touch or touchless?

“…the inability to understand the interaction modality of the display [13]). Gentile et al showed also that the presence of an avatar makes two-handed interactions more "natural", reducing the cognitive workload while interacting with public displays [21].…”

“…As already mentioned in section 2.1, the use of avatar-based interfaces has many advantages, including the ability of communicating the supported touchless gestural interactivity [33], and the reduction of the perceived cognitive workload, which should contribute to make the interactions more natural [21]. While adding the avatar to a gestural UI is crucial to make it reasonably effective, with touch-based interfaces the affordance of the display and the users' prior experiences can be considered sufficient to overcome these limitations [13].…”