Using nonverbal signals to request help during human-robot collaboration

Non-humanoid robots are becoming increasingly utilized for collaborative tasks that rely on each collaborator's ability to effectively convey their mental state while accurately estimating and interpreting their partner's knowledge, intent, and actions. During these tasks, it may be beneficial or even necessary for the human collaborator to assist the robot. Consequently, we explore the use of nonverbal signals to request help during a collaborative task. We focus on light and sound as they are commonly used communication channels across many domains. This paper analyzes the effectiveness of three nonverbal help signals that vary in urgency. Our results show that these signals significantly influence the human collaborator's and their perception of the collaboration.