Study on interaction-induced symptoms with respect to virtual grasping and manipulation

Owing to the popularity of various hand tracking interfaces, there have been numerous applications developed to provide intuitive hand interaction with the virtual world. As users start with great anticipation, they end up with dissatisfaction due to difficulties of manipulation or physical tiredness coming very short. Although the task itself is rather trivial in a real life situation, it requires much effort in the virtual environment. We address this awkwardness as ‘VR interaction-induced fatigue symptom’ and hypothesize its causes based on our observations. We argue that the source of the fatigue comes from the restricted sensory information of the VR interfaces, and that users try to accommodate the missing sensory feedback by excessive motion leading to wrong posture or bad timing. We demonstrate our hypothesis by conducting experiments of two types of virtual interaction scenarios: object transport and 3D selection. Furthermore, by analyzing the behaviors of users' action collected from our experiment, we derive essential factors to be considered in designing VR applications, and propose a conceptual interaction model for orchestrating virtual grasping.