Summary

There are two approaches to make a “soft robot”: one is to use soft material for body parts, and the other is to make soft actuators. In the second approach, backdrivability is important for a robot interacting with human. Out research group has been developed electro-hydrostatic actuators (EHAs) for robotic hands and a humanoid robot. An EHA has high backdrivability and precise force controllability because it directly connects hydraulic pump and hydraulic actuator without servo valve. Our next challenge is the first approach: to use soft material for body parts. In particular, contact parts in a robot such as hand or foot should be made of soft material to improve the contact stability. Combining soft material and hydraulic actuation, we develop a new robot hand, integrate it in a robot arm or humanoid system, and realize a stable contact motion control.