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The Space Shuttle was a fairly compact transportation vehicle in terms of the amount of space available for astronauts to move around. Did they ever attempt to roll a Space Shuttle to induce artificial gravity?

If not, why? It doesn't sound hard, just pump some air through the maneuver thrusters and off you go!

Fred
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    It would have to spin too fast because it it not big enough. – jkavalik Feb 15 '17 at 07:00
  • @jkavalik: For creating 0.05g? The force depends on the angular velocity. Also, most of its mass is in the rear; CoM pretty far back, cockpit on a long arm. Pitch or yaw rotation would create a considerable force in the maned area. – SF. Feb 15 '17 at 07:34
  • OTOH I wonder how dangerous it would be. The systems were never meant to handle continuous, lengthy acceleration in the front direction. – SF. Feb 15 '17 at 07:39
  • @SF. I supposed you would spin it in roll. Spinning it around its engines would make the artifical gravity point exactly against the liftoff acceleration. – jkavalik Feb 15 '17 at 07:40
  • I found http://www.artificial-gravity.com/sw/SpinCalc/ - in roll using 5m diameter (which is probably more than the internal space actually had but not sure) you get over 4 rpm which sounds a bit too much already just for your 0.05g. When I read the question I imagined at least 0.1-0.2g. – jkavalik Feb 15 '17 at 07:43
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    Related: Why are there no spacecraft rotating for artificial gravity? – user Feb 15 '17 at 07:44
  • @jkavalik: Worst, nausea-inducing gradient (stronger pull by the "floor", none at head level), and much faster spin, although likely safest - easiest to recover from if some RCS thrusters fail, and most fuel-conservative (thrusters on wingtips) – SF. Feb 15 '17 at 07:46
  • @SF. yes, not good for the crew. I tried 20 arm for your pitch rotation and got 1.5 rpm for 0.05g, much better. – jkavalik Feb 15 '17 at 07:48
  • Note RPM is rotations per minute. 4rpm is merely 1/15s. – SF. Feb 15 '17 at 07:55
  • @SF What if the astronauts were crouching? Strong pull everywhere = non-nausea-inducing gradient? :P –  Feb 15 '17 at 08:14
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    @frayment: lesser gradient, still large. Lying down would help. The question is: what for? – SF. Feb 15 '17 at 08:19
  • @SF Well I was doing some reading on gravity and asked myself: have they done it? And if not then why not? –  Feb 15 '17 at 08:32
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    'cause they didn't have beer on board, to pass to a friend saying "hold my beer and watch this!" ;-) No, seriously there are some mild reasons "why not" and not enough good reasons "why". – SF. Feb 15 '17 at 08:42
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    Might be more difficult to land with footprints on the windshield. – Steve Feb 15 '17 at 14:08
  • "It doesn't sound hard, just pump some air through the maneuver thrusters and off you go!" Where's that air coming from? – Lightness Races in Orbit Feb 15 '17 at 16:52
  • I could have sworn there was an experiment where they tumbled the Shuttle (slowly) to generate tension for a tethered-satellite experiment, but I've been unable to find it. – Mark Feb 15 '17 at 23:27
  • @LightnessRacesinOrbit RCS. The orbital maneuver system or simply the translation thrusters. –  Feb 16 '17 at 07:42
  • @frayment: RCS doesn't have an infinite supply, and this is not the best use of said supply ;) – Lightness Races in Orbit Feb 16 '17 at 09:59
  • @LightnessRacesinOrbit I don't believe that perhaps shooting it in the roll direction for a few seconds or so to gain momentum, and shutting it off won't be that bad :) Even then, your in space, drag wont slow you down, shoot it once and forget! –  Feb 16 '17 at 10:27
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    @frayment: Hmm good point – Lightness Races in Orbit Feb 16 '17 at 10:43

2 Answers2

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There are several reasons not to do this:

  • Artificial gravity in such a small space is not very pleasant. You'll get a noticeable difference in gravity in different places, which makes it difficult to move around without banging into the walls.

  • You also get coriolis forces (thrown objects don't move in a straight line) which makes moving around non-intuitive.

  • The Shuttle wasn't designed for it. When rotating around the pitch or yaw axis, the dashboard becomes the floor, and you don't want that. There were no ladders in that direction either so you have to climb on whatever's handy to move between decks. The operator station for the robotic arm becomes inaccessible.

Hobbes
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  • Haha fair enough. However what if there was theoretically only lets say one astronaut on board. And they were crouching. Would the gravity be much more sensible in terms of what is being exerted on parts of the persons body? –  Feb 15 '17 at 08:13
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    What would be the point of that, except to say, "yup, we can do it"? – Hobbes Feb 15 '17 at 12:57
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    Fourth reason: the Space Shuttle did not possess circular symmetry around any axis, which makes it awkward mechanically. – Mason Wheeler Feb 15 '17 at 16:18
  • "When rotating around the pitch or yaw axis, the dashboard becomes the floor, and you don't want that." Not sure I follow. The dashboard rotates with the ship and crew, no? Just like in a plane. – Lightness Races in Orbit Feb 15 '17 at 16:54
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    @LightnessRacesinOrbit it can only rotate about its center of mass so for both yaw and pitch rotation, the dashboard is farther away from it than the crew and becomes the floor of the created centrifuge. – jkavalik Feb 15 '17 at 17:00
  • When the ship rotates, the 'gravity' vector points outward from the center of rotation. So you would fall towards the outermost surface of the cockpit, i.e. the dashboard. Instead of standing on the floor, you'd have to stand on the dashboard. – Hobbes Feb 15 '17 at 17:00
  • @jkavalik: Oooooh! Heh. – Lightness Races in Orbit Feb 15 '17 at 17:05
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    @Hobbes: Okay yeah that seems unhelpful. Still, that just means you'd rotate about the remaining axis if you wanted to achieve this effect? – Lightness Races in Orbit Feb 15 '17 at 17:05
  • Rotation around the roll axis is worse: the roll axis runs lengthwise through the cockpit, so you'd be able to stand on the floor of the lower deck and the ceiling of the flight deck. Because you're so close to the roll axis the gravity gradient across your body would be worse, and you'd need to spin the spacecraft even faster to get appreciable G forces. – Hobbes Feb 15 '17 at 18:31
  • Fifth reason: Rotation around the pitch axis is unstable. There is an easy and cool parlor trick you can do so show this: put an elastic band around a book so it won't open, then try to rotate it along its 3 axes of symmetry. If you flip it "on edge" or "on its long edge", no problem. But if you flip it on its short edge (like the shuttle pitching over) it will tumble. – dkneller Feb 15 '17 at 20:11
  • @Hobbes: Got ya. – Lightness Races in Orbit Feb 16 '17 at 10:00
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The highest rotational rate ever achieved by a shuttle in orbit was only 3 degrees/second (approximate). This was inadvertently caused when Mission Control uplinked a bad state vector during crew sleep* and caused the vehicle to go out of control.

This rotation rate was not nearly enough to induce artifical gravity.

*incident is described on pages 2-4 and 7-25 of the pdf

Organic Marble
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    And 3 degrees per second is one full rotation every two minutes. – user Feb 15 '17 at 12:55
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    A more detailed description is on page 7-25 of the same document. Out of curiosity, do you have a citation for that being the highest rotational rate? – Tristan Feb 15 '17 at 15:23
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    Another retelling of that story: the caption file of a video of a lecture by Wayne Hale at MIT, beginning at caption 1585: https://ocw.mit.edu/courses/aeronautics-and-astronautics/16-885j-aircraft-systems-engineering-fall-2005/video-lectures/lecture-18/FB0pyYTs2mw.srt – Tristan Feb 15 '17 at 15:29
  • @Tristan I do not have a citation for that, just my recollection. With a lot of these questions, it's not whether you know the answer, but whether you can find a public source to reference. For that one, I have not. - And thanks for the comment about page 7-25, updating the answer. – Organic Marble Feb 15 '17 at 15:37
  • That Wayne Hale transcript also says rate was 3 deg/min, that conflicts with my personal notes which say 3 deg/sec. Take your pick. - Ah, I see he corrected himself later in the transcript. Whew! – Organic Marble Feb 15 '17 at 15:43
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    @OrganicMarble I find plenty of those situations as well. I almost wonder if there's a need for this site (and possibly others) to have some way to certify people who work in the industry and give answers informed by information that isn't necessarily public. The space industry is fraught with all sorts of data restrictions in this regard. Probably a good meta discussion. On a different note, I like the Wayne Hale lecture (there's video somewhere too) for the degree of storytelling that humanizes it beyond what official documents say. – Tristan Feb 15 '17 at 15:50