Although these actions are not sufficient
to represent all of human’s intentions, they could be
considered main features of a reaction when a human has a
specific intention. For example, when a human wants to ask
something, or play with the robot, he/she can ‘approach’ the
robot, while he/she can ‘depart’ when he or she desires to
finish the interaction. In addition, when a human is not
concerned with the robot, he/she can just try to ‘bypass’ the
robot. The ‘stop’ action does not need more explanations.