<p>Good questions!</p><p>I think the rationale is clear. EVA is a risky, time consuming, and labour intensive activity. Eliminating as many EVAs by use of both low and high end robotics is a desirable goal. I have In practice, I don't think it is so easy. </p><p>DEXTRE is the nearest so far to a human equivalent teloperated robot. But it can only replace astronauts on some routine tasks, and not on specialist ones. Which may be why it hasn't been used yet. EVAs to date have been associated with space station assemby, well beyond its capability. Once construction is finshed it may see more use.</p><p>DEXTRE, in addition to being an operation item, is an experiment in its own right, one in the validity of using high level telerobotics to replace EVAs. In practice it may not be so if after 10 years DEXTRE is only used for one EVA in 10 the experiment may have successfully shown that this is not a useful approach, which will be an important lesson</p><p>It is important to remember that DEXTRE has an operational cost, well beyond its dollar investment. It masses 1.5 tonnes and consumes 1.5 kW. This is not such an issue on the ISS which is large and has power to spare, but for Moon and Mars missions there may be better ways to use that mass and power.</p><p>cheers</p><p>Jon</p><p> </p> <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em> Arthur Clarke</p> </div>