
Artificial gravity breaks free from science fiction - curtis
https://www.colorado.edu/today/2019/07/02/artificial-gravity-breaks-free-science-fiction
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StillBored
This isn't artificial gravity, its just rotational force.

The wikipedia article even suggests that the solution to motion sickness is
slower rotation, achievable with larger diameters.

[https://en.wikipedia.org/wiki/Rotational_gravity](https://en.wikipedia.org/wiki/Rotational_gravity)

Says it takes a ~224M radius at 2 rpm to get earth gravity. Given the ISS is
108M wide seems pretty doable with current technology if we really wanted to.

There is also a pretty interesting chart here
[https://ase.tufts.edu/cosmos/view_picture.asp?id=748](https://ase.tufts.edu/cosmos/view_picture.asp?id=748)
about asteroid size vs rotational speed.

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byebyetech
This headline should win the clickbait of the year award.

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carapace
For shame colorado.edu, eh? I got actually angry for a minute.

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bayareanative
Don't let that go or you're condoning dishonesty.

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carapace
?

I already let it go, but I still don't condone dishonesty.

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slang800
This isn't "artificial gravity", this is just a centrifuge, and those have
been used for decades in High-G training. See:
[https://en.wikipedia.org/wiki/High-
G_training](https://en.wikipedia.org/wiki/High-G_training)

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Rerarom
I thought it was achieving gravity by means other than rotation :(

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Robotbeat
Hey, rotation works.

There was a NASA-funded NIAC proposal about using linear acceleration
(oscillating up and down in an elevator) to do the same thing, but it's pretty
strange compared to just using rotation.

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kbutler
Centrifugal and coriolis pseudo forces cause objects to act strangely in
rotating frames. Also, in small-diameter rotations, the tidal forces can be
very noticeable (differential acceleration on different parts of an object).

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Robotbeat
That’s what this article is about: those (primarily psychosensory) effects are
apparently able to be mitigated entirely with training.

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bayareanative
This title needs editing. It has nothing to do with gravity.

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igravious
Why not use this on Earth to build more robust humans, might be an athletic
training hack. Wouldn't you get the opposite of bone loss and muscle loss? So,
increased bone and muscle density. Must be good for something. Might be tough
on the cardiovascular system though.

Oh, and "artificial gravity"? Please already.

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keyle
This is cool and seen on many science fiction show. The engineer in my head
wonders, how do you make the transition between various 'donuts' compartments
and various levels without getting limbs chopped off? Only by the center via a
tube?

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burfog
You don't need to transition unless you want a microgravity lab or possibly
docking another spacecraft. Stopping is also an option, though debris and even
furniture might float around.

Picture a long truss connecting an office building to a nuclear reactor. It
spins end over end. There are multiple ways to connect a non-rotating part at
the middle.

One way involves an air lock. Pass through that, shut the door, and then
adjust the relative rotation.

Another way involves a large and troublesome seal. I suspect this might best
be done with ferrofluids to seal the gap.

Accepting a bit of air loss is another option. If the gap is tiny, it might
not be bad. It would just be part of the accepted loss, just like the loss
from spacewalks.

For docking, you could skip all that if you accept the complexity of docking
with a spinning object. You could even dock away from the center if the
rotation is slow enough.

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keyle
Thanks for your elaborated response!

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inamberclad
Ah yeah, professor Clark has been doing this for a few years. He's a cool dude
and the whole BioAstro group is really top notch.

I was very nearly a test subject in this experiment.

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legulere
For space travel I really like the idea to accelerate (and after halfway
decelerate) with 1g.

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dr_dshiv
Dumb question: in deep space, how do you "know" that you are spinning?

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akshayB
I think there are still lot of technical challenges to design something like
this for long space missions but the design needs lot of space and resulting
structure can be enormous.

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inamberclad
I'm pretty annoyed that this article doesn't mention it, but the whole point
of Prof. Clark's research is to find the human tolerance for rotation so that
these structures can be made as small as possible. I suppose the news here is
that his candidates made it to 17 rpm, which appears to be a new record.

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newnewpdro
Well that was disappointing

