1. a JST Erato Asada Synergistic Intelligence Project, Department of Adaptive Machine Systems, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan;, Email: shinya.takamuku@ams.eng.osaka-u.ac.jp
2. b JST Erato Asada Synergistic Intelligence Project, Department of Adaptive Machine Systems, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
3. c JST Erato Asada Synergistic Intelligence Project, Department of Adaptive Machine Systems, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan