ロボットへの教示場面における「間」の重要性：ロボットの行動の遅れは学習効率を向上させ教えやすい印象を与える

In the future, robots will support our work in our daily life. We believe that robots should learn desirable behavior through human-robot interaction. However, it is hard for humans to instruct the robots on all actions. It therefore is important that the robots can utilize rewards (evaluations) as well as instructions to reduce humans' efforts. Additionally, ``intervals'' which allow humans to give instructions and evaluations are also important because there are delays in giving them. We hence focused on ``delays in initiating actions of a robot'' and proposed a method of changing them according to the progress of learning: long delays at early stages, and short at later stages. In other words, if a robot is not sure about its action, it initiates the action laggardly, but if it is confident about its action, it initiates the action immediately. In this work, we conducted experiments on teaching AIBO to shake hands using instructions and evaluations under two conditions: Varying Condition under which the delays vary in accordance with the progress of learning, and Constant Condition under which the delays are set at medium constant. The result demonstrated that Varying Condition improves learning efficiency significantly and impresses humans as teachable.