On-Orbit Demonstration of Tether-Based Robot Locomotion in REX-J Mission.

Locomotion is an important factor affecting astronaut support robots that are used in construction, repair, and inspection. Its requirements include long reach, compactness, and light weight. Tether is a good candidate because it allows for a long reach but is very light. It is also compact when wound up. The authors have previously proposed a reconfigurable tether-based locomotion method. In the concept, the robot attaches/detaches its tethers to/from handrails on the spacecraft and moves by controlling the length and tension of the tethers. From August 2012 to May 2013, JAXA conducted the Robot Experiment on JEM (REX-J) mission, experimentally demonstrating the proposed method on the International Space Station. During the experiment, all the locomotion tasks were successfully completed. This paper describes the results of these locomotion experiments.