We are developing a robot that guides a user in a building to the destination room holding by the user's hand. We think that a robot and a human can adjust one's moving direction or position by communication with hands. However, conventional robot arms have two problems. First, the human is constrained within a range of the robot arm's movable scope and not easy to walk. Second, the robot arm is not safe enough when it collides with other people. Therefore, we propose a robot that has an expandable hand. It can follow the human flexibly by stretching/shrinking the hand held by the human. The hand is made with soft string, which ensures the safety. In this paper, we report the basic concept as well as the hardware configuration of the robot.
