Help-Estimator: Robot Requests for Help from Humans by Estimating a Person’s Subjective Time

In human–robot cooperation, it is effective for a robot to ask a human partner for help to reduce the time required for a task. However, the person might not be able to help the robot if she or he is engaged in something else. In this study, we focused on the person’s subjective estimation of the time for a task and investigated its effect on the likelihood of agreeing to help the robot. For this purpose, we developed a Help-Estimator system that decides whether the robot should request help by considering the required time for both the person and the robot to finish their tasks. We conducted an experiment to evaluate such help requests that incorporate the human’s subjective time estimation for a task. We found that appropriate timing for requesting help, as estimated from the person’s viewpoint, increases the likelihood of the person helping the robot and improves the person’s impression of the robot as a partner.