Transgazer: Improving Impression by Switching Direct and Averted Gaze Using Optical Illusion

To effectively utilize gaze in one-to-many communication, robots must direct and avert their gaze with appropriate timing. However, few studies have focused on this aspect of communication because of the difficulty in detecting the position of many gaze recipients and directing appropriate gazes to each. This paper proposes a system of robotic eyes that can send averted or direct gazes simultaneously to multiple recipients by switching between convex and hollow eye shapes, which we call Transgazer. Using Transgazer, we experimentally confirm that hollow eyes can direct a gaze more broadly whereas convex eyes can convey gaze direction more correctly. In our main experiment, Transgazer uses both eye types while giving lectures to two participants without precisely retrieving the gaze recipients' directions. Transgazer allows robots to gaze appropriately and enhances one-to-many communication, improving the audience's impression of the speaker.