1. BIOMOD 2015; Team Sendai; Tohoku University; Aoba-yama Sendai Miyagi 980-8579 Japan
2. Department of Robotics; Graduate School of Engineering; Tohoku University; Aoba-yama Sendai Miyagi 980-8579 Japan
3. Frontier Research Institute for Interdisciplinary Science; Tohoku University; Aoba-yama Sendai Miyagi 980-8579 Japan