1. Kyushu University,Faculty of Information Science and Electrical Engineering,Fukuoka,Japan
2. The University of Tokyo,Graduate School of Engineering,Department of Precision Engineering,Tokyo,Japan
3. RIKEN,CBS-TOYOTA Collaboration Center Intelligent Behavior Control Unit,Nagoya,Japan
4. RIKEN,Man-Machine Collaboration Research Team, Guardian Robot Project,Kyoto,Japan
5. Kyoto University,Academic Center for Computing and Media Studies,Kyoto,Japan