Development of an Astronaut Support Robot and its Precursor REX-J, to be tested on the International Space Station

A unique space robot is being developed by JAXA (Japan Aerospace Exploration Agency). Name of the robot is REX-J (Robot Experiment on ISS/JEM) and its mission is to evaluate technologies needed to realize the Astronaut Support Robot (Astrobot) and the next generation space robots (NGSR). Uniqueness of the robot is its locomotion method which is based on tethers. The robot is floated by tethers whose ends are attached to the robot and the other ends are attached to hand rails on the space station. The robot can change its location by changing lengths of each tether. The robot can also change its area to move by changing location of the tether’s end positions. Location of tether’s end position can be changed using the extendable robot arm. This unique robot arm is based on the Storable Tubular Extendable Member (STEM) which is widely used for years as deployable satellite antenna and whose mechanism makes the arm compact. At the time of the i-SAIRAS 2012 symposium, REX-J will be already launched and the initial check out will be conducted. However at the time when this paper is being prepared, REX-J is not yet launched. Therefore, this paper introduces development results and the onorbit experiment plan.