Exploring the effectiveness of body language in mitigating the face threat of robot noncompliance

Abstract

As the capabilities of robots have increased over recent years, more robots are being introduced to society as "social robots." Social robots harbor the ability to communicate with their human counterparts in order to complete a task. Because of this, social robots need to be able to observe the same ethical and social norms that humans do - lest they inadvertently defy those norms. To this end, a social robot may even be required to deny a problematic command issued to it on moral grounds. Previous work has demonstrated the importance of carefully tuning the severity of command rejections in the effort of saving face with the commanding entity. However, previous work has not considered the subtle communication that body language has to offer. Body language, specifically gaze and gesture, are important modes of communication in human-human interaction, and have been demonstrated to be just as important in human-robot interaction. As such, we posit that robotic gaze and gesture must be carefully chosen with respect to vocal phrasing when rejecting a command. We present a series of human-subjects experiments in which robotic gaze, gesture, and vocal phrasing are varied when rejecting commands of differing severity.