Modeling of natural human-robot encounters

For a person to feel comfortable when approaching a robot it is necessary for the robot to behave in an expected way. Peoplepsilas behavior around a robot not being aware of them were observed during a preliminary experiment. Based on those observations people were classified into four groups depending on their interest in the robot. People were tracked with a laser range finder based system, and their positions, directions and velocities were estimated. A second classification based on that information was made and the relation between the two classifications were mapped. Different actions were created for the robot to be able to react naturally to different human behaviors. In this paper we evaluate three different robot behaviors with respect to how natural they appear. One behavior that actively tries to engage people, one that passively indicates that people have been noticed and a third that makes random gestures. During an experiment test subjects were instructed to act according to the groups from the classification based on interest, and the robotpsilas performance with regard to naturalness was evaluated. Both first and third person evaluation made clear that the active and passive behavior were considered equally natural, while a robot randomly making gestures was considered much less natural.