An embodied entrainment avatar-shadow system to support avatar mediated communication

Shadow is significant for an effective projection of real objects and has an important role in three-dimensional effects and reality of virtual space. Therefore, an avatar´s shadow should have interactive effects with the avatar´s self in a virtual space. In our previous research, we reported that an auto-generated interactive avatar´s motion that is different from the talker´s own motion does not always support human communication. However, using an avatar-shadow, talkers can communicate effectively, without inconsistency between their own motions and their avatar´s motions in a virtual space in which the avatar-shadow´s motions are expressed by combining the talker´s own motions with auto-generated interactive motions. Accordingly, we propose an embodied entrainment avatar-shadow system. This system is composed of the talkers´ avatars and their avatar-shadows based on their own motions and auto-generated entrained motions. In addition, we develop a prototype from three viewpoints for a more effective use of the avatar-shadow. In this paper, we perform two conversation experiments to study the effects of the avatar-shadow using sensory evaluation. The first experiment is a role-play experiment in which two subjects play roles of a speaker and a listener. The second one is a free conversation experiment in which two subjects talk about daily life. The results of the sensory evaluation experiments allow us to demonstrate the effectiveness of the avatar-shadow´s existence and the auto-generated nodding response.