Evaluation of Robots that Signals a Pedestrian Using Face Orientation Based on Moving Trajectory Analysis

Robots that share daily environments with us are required to behave in a socially acceptable manner. There are two important approaches to this purpose: 1) robots model human behavior, understand it properly and behave appropriately 2) robots present their understanding and future behavior to surrounding people. In this paper, considering people present various cues to other people around them using gaze and face direction, we focus on the latter approach and propose a robot that presents cues to an opposing pedestrian by turning face. Another problem with the conventional research is that the evaluation of the pedestrian's ease of passing with the robot depends only on the subjective impression, so it was difficult to design the robot's behavior based on the temporal change of the ease of walking. In this paper, we evaluate the fluctuation of the pedestrian's moving velocity vector as an index of the ease of walking and analyze the temporal change. We have conducted preliminary experiments in which 12 subjects passed by the robot and compared the three types of presentation methods using the face. By presenting information using a face, we confirmed that the subjects tended to have better impressions of walking based on subjective evaluation and that the walking was relatively easy to walk for several seconds while approaching the robot based on analyzing the fluctuation of the moving speed vector.