The Feeling of Kawaii toward a Robot's Head-Tilting Motion: Effects of Speed, Direction, and Accompanying Hand Gestures

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.