Is Symbolic Gestural Interaction Better for the Visual Attention?

Abstract

Thanks to improvements of the last decades in the robotic field, small Unmanned Aerial Vehicle (sUAV) have become efficient remote sensors for infantrymen on the battlefield. Their increasing mobility and autonomy allow acquiring essential strategic information in a constantly evolving environment. However, due to the hostile nature of the battlefield, a soldier cannot focus on screen-based interfaces currently in use. Although being robust, touch screen interfaces induce physical and cognitive loads that can affect mobility, efficiency and safety. In this context, symbolic gestural interaction (SGI) seems a good alternative. It uses a Gestural Vocabulary (GV) that associates exactly one gesture per functionality. Gestures can be executed almost at any time without material preparation. Moreover, and contrary to touchscreens, gestures require no visual feedback since they benefit from the proprioception. This can lead us to believe that better environment awareness for the operator is possible. However SGI requires that semantic items are learnt and recalled on time to be correctly used. This may impose a cognitive load that could counterbalance the benefit of not having to look at a screen. As there has been no evidence so far, a comparative evaluation has been conducted. In a dual-task experiment, 20 volunteers were requested to carry out a primary task (detect and signal visual targets) and simultaneously to command a virtual sUAV on demand, either using SGI or a touchscreen. Results indicated that SGI disturbs less the visual attention as the reaction time (RT) in the primary task was significantly shorter. Thus, this study suggests that SGI is a well-suited alternative to standard HMI for infantrymen on the battlefield.