Artificial gravity experiments?

[Epidemic]

Ok we have been in space for 50 years now. I still have not heard of a single centripetal force experiment where they stick 2 cans on the end of a catwalk which spins fast enough to simulate gravity.

Gravity seems to be the largest problem with the human body in space, why are they not testing a simple system to produce gravity.

Every single sci-Fi show has either magic artificial gravity or some form of a spinning ship.

0-------0 does not seem to be all that difficult with current technology.

0----0----0 This could kill multiple birds with one stone zero -g in the middle for experiments.

Instead we glue 25 tin cans together and call it the International space station.

have we done any experiments with artificial gravity yet? (I have heard of none)

[John Prophet]

I have fantasized about a piece of exercise equipment in which you step into a chamber and they turn on the gravity field generator and basically the gravity is such that you cant move....so to even walk to the other side of the chamber or raise your arms would be killer exercise

[GroundZero3]

JP watch dragon ball z much?

[Epidemic]

I think it is far from fantasy.

The simplest experiment would be two modules slated for the ISS beefed up and tied together with a 20 or 30 meter cable spin the thing up to 1 or 2 RPM and poof instant gravity.

[Gomer]

google is your friend!

http://www.google.com/search?hl=en&i...=Google+Search
#1 on the list:
http://www.spacefuture.com/archive/a...habitats.shtml

In a rotating system, one must also consider the non-intuitive effects of angular momentum. To turn an object about some local axis, in an environment that is rotating about some other global axis, requires a moment about a third axis perpendicular to the other two. The moment is proportional to the vector product of the environment's angular velocity and the object's angular momentum. The non-aligned rotations about the global and local axes are said to be "cross-coupled".

For example, consider a person standing in a rotating orbital habitat, facing prograde. The habitat may resemble a giant bicycle wheel. Artificial gravity aligns his apparent vertical axis along a radius or "spoke" that rotates with the habitat. The habitat's rotation axis is over head, horizontal in his frame of reference, directed left-to-right. As long as he remains motionless relative to the habitat, he rotates with it effortlessly. When he turns to his left, he adds vertical components to his angular velocity and momentum. His angular momentum is no longer aligned with the habitat's angular velocity. To sustain this leftward turn about his vertical axis (while that axis rotates with the habitat) requires a left-leaning moment about his front-to-back axis. Moreover, this leftward turn about his vertical axis induces effects on his vestibular organs as if he was rotating about his front-to-back axis.

Experiments with human subjects in centrifuges and rotating rooms have confirmed this. When subjects turn their heads about any axis that is not aligned with the rotation of the environment, they experience vestibular illusions of rotation about a perpendicular axis. The illusions are approximately proportional in magnitude and direction to the vector product of the angular velocities of the environment and the head [23, 24]. The resulting mismatch between the vestibular and visual senses of motion are believed to be a major cause of motion sickness [4, 5]. To minimize these illusions while permitting the normal range of human motion, the angular velocity of the environment should be kept low.

Unfortunately, when the radius is limited, reducing the angular velocity may increase other aspects of gravitational distortion. One measure of this distortion is the ratio of the magnitudes of the Coriolis and global centripetal accelerations. To emulate a natural gravitational environment, this ratio should be minimized without constraining the relative motion of people or objects within the environment.

The design of an orbital habitat for artificial gravity depends on much more than physics. A few simple formulae relate the habitat's size and rotation to the apparent gravity. Unfortunately, the formulae are powerless to predict the satisfaction of the inhabitants. Many empirical studies have attempted to identify the comfort boundaries for artificial gravity, to constrain the values of the variables. Nevertheless, they have arrived at substantially different conclusions. The disagreement may be due in part to different assumptions regarding the mission, selection, motivation and adaptability of the target population. To support a large clientele, it may be safe to stay within the common ground of all of the empirical studies, choosing the most restrictive bounding value for each variable.

Ultimately, an inhabitant's ability to adapt to artificial gravity will depend on how well the habitat itself is adapted. As a matter of principle, it is probably not possible to design for artificial gravity without having lived in it. Nevertheless, in designing the first such habitats, one must make the effort.

[John Prophet]

have heard of DBZ but never watched it

[EpyonMelee]

JP watch dragon ball z much?

hyper bolic time chamber

[Epidemic]

http://www.spacefuture.com/archive/a...habitats.shtml

I like that link.

Thanks gomer. I did the same search but did not "artificial Gravity"

Discompfort level seems to simply be a function of the distance between modules or rather the radius. Larger radius and slower rotational speed reduces disorientation.

Any idea why they have not tested this on a human scale. I mean mice are one thing

[Chuckiechan]

If and when interplanetory travel occurs, it is logical to have the space craft to accelerate at one G on the trip to the planet, then turn around and decelerate at one G when the "deceleration point' is reached.

Thus, our travelers will have mostly normal gravity for most of the trip. Deciding on the fuel to produce the acceleration is the challenge.

[OuTpaTienT]

If and when interplanetory travel occurs, it is logical to have the space craft to accelerate at one G on the trip to the planet, then turn around and decelerate at one G when the "deceleration point' is reached.

Thus, our travelers will have mostly normal gravity for most of the trip. Deciding on the fuel to produce the acceleration is the challenge.

I don't understand how that would work. Wouldn't everything on the ship, once it caught up to the acceleration speed of the ship (almost immediately) then lose that artificial gravity?

[elmers]

No since gravity is acceleration not speed. All the objects are constantly gaining speed, and therefor experience gravity.

Arthur Clarke proposed this in 2060.

"Gravity seems to be the largest problem with the human body in space."
Lack of gravity is not a problem in space, its an advantage.

[Warthog]

google is your friend!

No!!! Those words must not be spoken here...

Arthur Clarke proposed this in 2060.

In 2060? Fascinating. Somebody has been watching too much Bill & Tedd's Excellent Adventure...

Warthog

[elmers]

2060 = 2060: Odissey three

http://www.voidspace.org.uk/books/20...ey%20three.zip

"Universe was the first spaceship ever built to cruise under continuous acceleration, except for the few hours of the mid-course 'turnaround'. "

[OuTpaTienT]

Ok, continuous acceleration. That makes sense except for the fact wouldn't it have to eventually reach a point where it could no longer accelerate? Since the speed of light is the "speed limit" it stands to reason the ship would sooner or later reach a speed that would be it's fastest possible speed, and no more acceleration would be possible.

I guess then the ship could turn around and use deceleration for gravity and sacrifice mission travel time for the sake of making gravity. Then at a certain point start acceleration again and so forth.

[elmers]

First off the speed of light is like 300000 km/s which is a significant margin. Getting to 10000km/s is fast enugh for the solar system exploration.

Second what Clarke said is that the ship would constantly accelerate until it reaches the halfway point, then turn around and decelerate until for the other half.

[originel]

you forgot a 0 elmers. it's 3000000km/s we definitely wouldn't have to worry about reaching that limit any time soon. 2060 was a good book. If I remember correctly they used a fission engine fueled by water. I haven't read 3001 yet though.

[Epidemic]

original,

300,000 km/s is correct.
186,000 miles/s*1.6 =~300000km

[originel]

ack, you're right. Stupid k in front of the m, making me not think straight I always just think of c as 3x10^8m

[elmers]

"If I remember correctly they used a fission engine fueled by water."

They did something with water, im not sure what tho BTW 3001 is more like 2060, and less like 2001 and 2010. I didnt really like it i just had to read it bc i read the first three.

[loftezy]

Ok, continuous acceleration. That makes sense except for the fact wouldn't it have to eventually reach a point where it could no longer accelerate? Since the speed of light is the "speed limit" it stands to reason the ship would sooner or later reach a speed that would be it's fastest possible speed, and no more acceleration would be possible.

I guess then the ship could turn around and use deceleration for gravity and sacrifice mission travel time for the sake of making gravity. Then at a certain point start acceleration again and so forth.

No, acceleration can also be achieved through a change in direction. As the space station spins, the objects in the station are constantly accelerating because the normal vector is constantly changing.