An integrated approach of attention control of target human by nonverbal behaviors of robots in different viewing situations

A major challenge in HRI is to design a social robot that can attract a target human's attention to control his/her attention toward a particular direction in various social situations. If a robot would like to initiate an interaction with a person, it may turn its gaze to him/her for eye contact. However, it is not an easy task for the robot to make eye contact because such a turning action alone may not be enough to initiate an interaction in all situations, especially when the robot and the human are not facing each other or the human intensely attends to his/her task. In this paper, we propose a conceptual model of attention control with four phases: attention attraction, eye contact, attention avoidance, and attention shift. In order to initiate an attention control process, the robot first tries to gain the target participant's attention toward it through head turning, or head shaking action depending on the three viewing situations where the robot is captured in his/her field of view (central field of view, near peripheral field of view, and far peripheral field of view). After gaining her/his attention, the robot makes eye contact only with the target person through showing gaze awareness by blinking its eyes, and directs her/his attention toward an object by turning its eyes and head cues. Moreover, the robot can show attention to aversion behaviors if non-target persons look at it. We design a robot based on the proposed approach, and it is confirmed as effective to control the target participant's attention in experimental evaluation.