Tomomi Onuki

Effect of robot’s gaze behaviors for attracting and controlling human attention

Abstract Controlling someone’s attention can be defined as shifting his/her attention from the existing direction to another. To shift someone’s attention, gaining attention and meeting gaze are two most important prerequisites. If a robot would like to communicate a particular person, it should 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 effective in all situations, especially when the robot and the human are not facing each other or the human is intensely attending to his/her task. Therefore, the robot should perform some actions so that it can attract the target person and make him/her respond to the robot to meet gaze. In this paper, we present a robot that can attract a target person’s attention by moving its head, make eye contact through showing gaze awareness by blinking its eyes, and directs his/her attention by repeating its eyes and head turns from the person to the target object. Experiments using 20 human participants confirm the effectiveness of the robot actions to control human attention.

Controlling human attention through robot's gaze behaviors

Controlling someones attention can be defined as shifting his/her attention from the existing direction to another. However, it is not easy task for a robot to shift a particular humans attention if they are not in face-to-face situation. If the robot would like to communicate a particular person, it should turn its gaze to that person and make eye contact to establish mutual gaze. However, only such a turning action is not enough to set up eye contact when the robot and the target person are not facing each other. Therefore, the robot should perform some actions so that it can attract the target person and meet their gaze. In this paper, we present a robot that can attract a target persons attention by moving its head, make eye contact through showing gaze awareness by blinking its eyes, and establish joint attention by repeating its head turns from the person and the target object. Experiments using twenty human participants confirm the effectiveness of the robot actions to control human attention.

Model for controlling a target human's attention in multi-party settings

It is a major challenge in HRI to design a social robot that is able to direct a target humans attention towards an intended direction. For this purpose, the robot may first turn its gaze to him/her in order to establish eye contact. However, such a turning action of the robot may not in itself be sufficient to make eye contact with the target person in all situations, especially when the robot and the person are not facing each other or the human is intensely engaged in a task. In this paper, we propose a conceptual model of attention control with five phases: attention attraction, eye contact, attention avoidance, gaze back, and attention shift. We conducted two experiments to validate our model in human-robot interaction scenarios.

Attracting and controlling human attention through robot's behaviors suited to the situation

A major challenge is to design a robot that can attract and control human attention in various social situations. If a robot would like to communicate 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 in all situations, especially when the robot and the human are not facing each other. In this paper, we present an attention control approach through robots behaviors that can attract a persons attention by three actions: head turning, head shaking, and uttering reference terms corresponding to three viewing situations in which the human vision senses the robot (near peripheral field of view, far peripheral field of view, and out of field of view). After gaining attention, the robot makes eye contact through showing gaze awareness by blinking its eyes, and directs the human attention by eye and head turning behaviors to share an object.

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 humans 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 participants 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 participants attention in experimental evaluation.

Designing robot eyes for gaze communication

Human eyes not only serve the function of enabling us “to see” something, but also perform the vital role of allowing us “to show” our gaze for non-verbal communication, such as through establishing eye contact and joint attention. The eyes of service robots should therefore also perform both of these functions. Moreover, they should be friendly in appearance so that humans may feel comfortable with the robots. Therefore we maintain that it is important to consider gaze communication capability and friendliness in designing the appearance of robot eyes. In this paper, we propose a new robot face with rear-projected eyes for changing their appearance while simultaneously realizing the sight function by incorporating stereo cameras. Additionally, we examine which shape of robot eyes is most suitable for gaze reading and gives the friendliest impression, through experiments where we altered the shape and iris size of robot eyes.

Vision-based attention control system for socially interactive robots

A social robot needs to attract the attention of a target human and shift it from his/her current focus to what is sought by the robot. The robot should recognize the current targets attention level to smoothly perform this attention control. In this paper, we propose a vision-based system to detect the level of attention or willingness of the target person towards the robot and to control his/her attention. The system estimates the attention level from rich visual cues of humans face and head. Then, by timing targets attention to determine the appropriate attention level, it generates aware signals and makes eye contact with the target. Finally, the robot shifts the targets attention to an intended direction. The experimental results reveal that the proposed system is effective in controlling the targets attention.

Designing Robot Eyes and Head and Their Motions for Gaze Communication

Human eyes not only serve the function of enabling us “to see” something, but also perform the vital role of allowing us “to show” our gaze for non-verbal communication. The gaze of service robots should therefore also perform this function of “showing” in order to facilitate communication with humans. We have already examined which shape of robot eyes is most suitable for gaze reading while giving the friendliest impression, through carrying out experiments where we altered the shape and iris size of robot eyes. However, we need to consider more factors for effective gaze communication. Eyes are facial parts on the head and move with it. Thus, we examine how the robot should move its head when it turns to look at something. Then, we investigate which shape of robot head is suitable for gaze communication. In addition, we consider how the robot move its eyes and head while not attending to any particular object. We also consider the coordination of head and eye motions and the effect of blinking while turning its head. We propose appropriate head and eye design and their motions and confirm their effectiveness through experiments using human participants.

Robotic system controlling target human's attention

Attention control can be defined as shifting peoples attention from their existing direction toward a goal direction. If a human would like to shift anothers attention, s/he may first turn his/her gaze to that human to make eye contact. However, it is not an easy task for a robot when the human is not looking at it initially. In this paper, we propose a model of attention control with four parts: attention attraction, eye contact, attention avoidance, and attention shift. To initiate attention control process, the robot first tries to gain the target persons 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 his/her attention, the robot makes eye contact through showing gaze awareness by blinking its eyes, and directs his/her attention to an object by turning both its eyes and head. If a person other than the target seems to be attracted by the robot, the robot turns its head away from that person to avoid his/her attention. Evaluation experiments confirmed that the proposed approach is effective to control the target persons attention.

Design of robot eyes suitable for gaze communication

Human eyes not only serve the function of enabling us “to see” something, but also perform the vital role of allowing us “to show” our gaze for non-verbal communication. The eyes of service robots should therefore also perform both of these functions. Moreover, they should be friendly in appearance so that humans may feel comfortable with the robots. Therefore we maintain that it is important to consider gaze communication capability and friendliness in designing the appearance of robot eyes. In this paper, we propose a new robot face with rear-projected eyes for changing their appearance while simultaneously realizing the sight function by incorporating stereo cameras. Additionally, we examine which shape of robot eyes is most suitable for gaze reading and gives the friendliest impression, through experiments where we altered the shape and iris size of robot eyes.