Humans shake hands as a sign of greeting, when they first meet one another, to express a feeling of rapport. For interactions involving a human and a robot, if the robot generates a handshake behavior that is emotionally acceptable to humans, it will lessen any feeling of aversion that the human has when initiating an interaction with the robot. For this reason, in our previous study, a handshake request motion model was proposed, where the robot generated a handshake behavior for the case when the robot actively approached a human. In this model, we studied the motion of a robot actively approaching humans, the handshake request motion from the robot and the start timing of the handshake. However, to promote embodied interaction smoothly, it is necessary for the robot to respond to the handshake requested by humans while still approaching them. Therefore, we developed a handshake robot system that generated a handshake behavior according to the request and response situation while actively approaching a human. First, a handshake response motion model for a handshake with active approach toward a human is proposed, based on an analysis of human handshake behaviors. In this model, the robot generates the response motion while it approaches the human. Furthermore, a switching handshake control with the active approach is developed where the robot generates either the request motion or the response motion, for a handshake according to the behavior of the human. By sensory evaluations, the effectiveness of the robot system using a switching handshake control was demonstrated.
