In the near future, robots are expected to actively participate in our daily lives. Once this time arrives, they will need to be socially accepted by people in various communities. However, the issues remain unknown that must be solved to make robots socially accepted. We have conducted a long-term experiment that a communication robot interacts people daily in an office. From the questionaire answers for the experiment, we have found that three fundamental issues, offering familiarity, reading the situation, and playing a social role, are required for a robot that is socially accepted. In this paper, we propose a hypothesis that three fundamental issues must be fulfilled by a socially accepted robot. Then, we tested our hypothesis through a six-week experiment in an office. We present the details of the experimental results and discuss what is the most important issue among them for a socially accepted robot.
