Extraction of behavior primitives in human standing-up motion for development of power assisting machine

Recently, many older people have difficulty standing up despite that motion´s importance in daily life. Therefore, a machine to support their standing-up motion is needed; yet we still do not know how people control their motor system when they stand up. For that reason, we can not produce such a machine. In this study, we analyze the system of people´s standing-up motion using information related to muscle activity. Muscle synergy-coherent activations of groups of muscles are an efficient means to achieve this goal. The results of experiments demonstrate the importance of muscle synergies that exist when people stand up.