Head-tilting motions are social signals that play a key role in communication. In human-robot interaction, researchers have found that this motion increases the observer’s feelings of kawaii toward a robot. Kawaii is a Japanese word meaning cute and adorable, and the feeling of kawaii refers to such affectionate, tender feelings toward an object. The feeling of kawaii has proven to be crucial for designing socially acceptable robots. However, the impact of the head-tilting speed of social robots on the observer’s kawaii feelings remains unclear because previous research mainly used static images. This study determined the optimal head-tilting speed and direction to deepen the observer’s feeling of kawaii toward a robot. Our findings found that participants reported feeling more kawaii toward a robot when it tilted its head to its right within 0.5 or 1 second. Our results also showed that gestures associated with head tilting are critical for robot behavior design.

“Kawaii” is a popular word in Japan today. Although it is often translated as “cute” in English, its meaning and scope are broader than those of “cute,” because this word is used not only as an adjective that describes the perceivable features of an object, but also as an adjective that expresses a person's feelings toward the object. In this talk, I will explain how “kawaii” can be conceptualized in the cognitive and behavioral sciences and how it is relevant to the field of human-robot interaction. First, I will introduce Lorenz's (1943) seminal concept of “Kindchenschema” (baby schema), which proposes that specific physical features, such as a round head shape and large eyes set lower on the face, serve as key stimuli that instinctively trigger nurturance behavior and the affective feelings associated with it in humans. I will then describe some recent empirical findings suggesting that the feeling of “kawaii” goes beyond a response to infantile stimuli and is better seen as a more general, positive emotion related to sociality and approach motivation. Finally, I will discuss the importance of this emotion in designing a desirable environment in which both humans and robots are included.

Kawaii, a Japanese word that means "cute," is an essential design concept in consumer and pop culture in Japan. In this study, we focused on a situation where a social robot describes an object during an information-providing task, which is commonly required for social robots in daily environments. Since past studies reported kawaii feelings are associated with a motivation to approach a target, our robot expressed feelings of kawaii to objects touch behaviors. We also focused on whether touch behaviors that emphasize style increase the feeling of kawaii of the touched object, following a phenomenon where people strongly touch a target when they overwhelmingly feel positive emotion: cute aggression. Our experimental results showed the effectiveness of touch behaviors to express the feelings of kawaii from the robot toward objects and to increase the participants' feelings of kawaii toward the object. We identified fewer effects from the participants to the robot. The emphasized motion style did not show any significant effects for the kawaii feelings.