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NASA's 20-G Centrifuge Machine
Roland Piquepaille writes "Scientists from NASA and two U.S. universities are using a 20-G centrifuge machine that can simulate up to 20 times the terrestrial gravity to evaluate the effects of hypergravity on humans. This 58-foot diameter centrifuge has three cabins, one for humans -- limited to 12.5 G -- and two for objects and flying hardware. The goal of these experiments is to reduce the adverse effects that space travel can have on astronauts' physical heath. But by studying the health benefits of exercise on astronauts, the researchers also hope to help the rapidly growing senior population who, like astronauts, doesn't exercise much. Read more for additional details and pictures about this NASA's machine."
58.88 m/s, or 131.72 mph, or 211.98 km/hr.
'Yes, firefox is indeed greater than women. Can women block pops up for you? No. Can Firefox show you naked women? Yes.'
Amazing 2 in 1 machine assists in space research while extracting information from uncooperative terrorists! A bargain for your tax dollars!
You have tried to support your argument with faulty reasoning! Go directly to jail; do not pass Go, do not collect $200!
That depends on how good you are at reading orthographic projections.
Bonsai Kitten: TNG
I've personally wanted to play around with a "high gravity" machine for a long time. Training in one would be the ultimate experience for any athlete I'm sure. I just wonder if the intense G's would actually strengthen your organs and bones by stress-testing them, so to speak, or just weaken them. Probably the latter.
Ginga no Rekshiya Mata Each page.
help the rapidly growing senior population who, like astronauts, doesn't exercise much
This seems like a really expensive way to prove that both groups just need to exercise more...
ZuluPad, the wiki notepad on crack
I just want to know if it can mix a good margarita. My machine broke.
this National Aeronautics and Space Administration's machine. Sounds speculative about the existence of NASA, but no problems besides that.
Ninjas and pirates. How piquant.
The word "terrestrial" comes from the Latin word terra "Earth" (in turn from PIE *ters- "dry [ground]", see Sihler's New Comparative Grammar ). While arguing from etymology is not always valid, I daresay that in this case if one simply says "terrestrial gravity", it's logical to assume to refers to the Earth's gravity, and not that of the moon or other planets, which have their own appropriate adjectives.
terrestrial P Pronunciation Key (t-rstr-l)
adj.
Of or relating to the earth or its inhabitants.
I think the pressures they are referring to would be experienced during launch, not during spaceflight.
I've got a chance to meet a few when I was working on a college project a few years back that had Nasa ties.
Don Pettit, former ISS Science Officer, was up for around 6 months. You'd think he'd be like that Russian who was too weak to walk and had a critical loss of bone density.
Nope. He got up, and with in a week was running 10 miles or more a day. He lost essentially no bone density. Freaking fantastic shape he's in. All the astronaut core is like that. It's all about constant exercise and having impact exercise.
I'd say more, but my guild is raiding.
I'm trying to remember where, but I read some author positing that given our experience with Earth languages, that if ever we meet any extra-terrestrials, no matter how many, that in their native language, the name of their home planet will most likely to translate to "dirt" just like it does for us.
--Carlos V.
Now I can finally become a Super-Saiyan!
From the description, it would also seem that the mere *subject* of high gravity reduced the cognitive functions, impairs the ability to write clearly, and generally gives one the appearance of brain damage. I suppose it was written while sitting in the machine in such a way that blood was forced to the back of the brain, away from the frontal lobes.
;)
Now to see how many people comment on my own writing abilities as a sign of my equally deteriorated mental state.
a 20-G centrifuge machine that can simulate up to 20 times the terrestrial gravity
Geez, no shit sherlock. I wonder how much G earth gravity is?
I can understand if this bit of info has to be included in say a BBC report but this is supposed to be a place filled with geeks and nerds who could work out for themselves that 20G is 20 times the G force of earths gravity. Even the americans should be able to handle the math involved. The canadians might need help. The dutch? It is sunday morning. To stoned to care. Not that it being sunday morning has anything to do with that.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
Zoidberg: Relax, Fry. I'll simply spin you in a high-speed centrifuge, separating out the denser fluid of His Highness.
Fry: But won't that crush my bones?
Zoidberg: Oh, right, right, with the bones! I always forget about the bones.
Is it not generally assumed that when talking about units of garvity and it's not specified otherwise, it's the Earth's gravity that they're using? I'm sorry, but I'm betting that anyone who read that and thought they were talking about the gravity on Mars is on Crack.
Someone save me from this sanity.
Um...Sorry to break it to you but...
"Terrestrial gravity" is, by definition, the gravity experienced on Earth, 3rd planet of our solar system.
If they meant the Moon (as in, the large body orbiting the Earth) they would have written "Luna gravity".
For Mars, it would be "Martian gravity".
For Jupiter, it would be "Jovian gravity"
No sig. Move along - nothing to see here.
While one should be skeptical that pressures as great as 12.50G let alone 20.00G would ever be experienced during space travel (space being weightless, this would I imagine be largely of concern only to a craft piloted foolishly close to a black hole)
Erm, acceleration, dude. If we get a drive that lets us do so, the quickest way to get to alpha centurai will be to accelerate as fast as we can halfway and decellerate the other half.
I am trolling
I think the biggest benefit of this type of research is in learning about how the human body reacts to the exercise stimulus in 1 G, 2 Gs, and so on. Exercise in space is about the only way very healthy 20-30 year olds don't have serious osteoporosis symptoms after spending some time on the ISS, and to a much lesser degree the shuttle. The human body doesn't maintain bone mass, or muscle tissue if it doesn't need it. Zero gravity is the maximum example of not having any need for bone mass and muscle tissue. Throw a centrifuge onto a space station/craft and the occupants might actually be able to walk and move on their own power after a stint in space.
Also a G is a unit of acceleration if I remember my physics right.
Heroscape, it's like legos combined with anachronistic wargames.
If we had a 20-g constant-boost drive, it could get our pulped remains to Pluto in two and a half days.
Erm, actually, capital case "G" is the universal gravitational constant ( 6.67300 × 10-11 m3 kg-1 s-2), and the only "unit" of acceleration is length per time squared. The acceleration due to gravity (at the poles and at a radial distance equal to the mean radius of the earth 6 378.1 kilometers) is denoted by small case "g" (~9,8 m.s^2 or 32 ft/s^2 for the Americans) and is not a good "unit" per se (because it's not really constant).
Oh, and just FYI for everybody, there is no "acceleration", "pressure" or "force" directly experienced inside a centrifuge. What is experienced is a non-inertial pseudoforce which is the result of transforming to an accelerated frame.
l'Homme n'est Rien l'Oeuvre Tout: Gustave Flaubert to George Sand
This is NOT your father's merry-go-round or Ferris wheel...
But, NOR is it a torture device, or a gas chamber... It's a reincarnation *acceleration* chamber...(think Reagan era comments on the gas chamber...)
Officially, it's an Information Secretion Device, though it can cause EXcretion and catonia and rapid weight loss, circulatory problems and acute inverse osteoporosis... But, primarily it has variable speed success at inducing persons of interest to secrete secret informations under otherwise unpossible nomral-g sitiations......
Indeed, in the spirit of extracting every valuable penny's worth of information, we will TAX the shit out of all subjects subject to the newly-improved "Salad Spinner", aka "Vegetable Maker". The resulting past is tronger than vegemite...
Talk about extracting information (from terrorists OR from science subjects) at "dizzying speeds"
Now, just put James Bond in THAT intense G-force. I imagine almost ANYone would be "impregnable" under those harsh circumstances...
Say, has anyone got a torch? It's quite dark in heeeeeeeee!!!!!!!!!!!
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
How are sites slashdotted when nobody reads TFAs?
Nevermind Gitmo... some of these could end up in Guam, Diego Garcia, some hinterland island of the Philippines... some afloat Prison/Afloat Mobyle Einformation Extraction Fasility... anyplace where US anti-torture laws would "normally" appall, umm, apply...
Would the human inside count as a power source? If the device is properly balanced, the human inside this habit-trail might make this thing qualify as some sort of perpetual motion machine. Maybe NASA will get the first patent!
We, NASA, on behalf of DHLS, claim an apparatus enabling the constant motion of a machine, which comprises a dense food and water supply, hope-inspiring-but-useless escape tools, and a plurality of combative but resilient human subjects contained therewithin, intent on fortuitously arriving upon or fervently concocting escape plans, inducing perpetual motion of embodied device.
Further uses of this device are classified under various secrecy acts and are exempt from disclosure
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
Of course space is wieghtless, but when taking off into space, there is gravity, and a shit ton of G force, I think I heard its around 9gs, but I'm not sure.
Bond: How fast does it go?
Goodhead: It can go up to 20Gs, but that would be fatal. 3Gs is equivalent to take-off pressure. Most people pass out at 7.
Bond: You make a great saleswoman.
Goodhead: You don't have to worry. This is what we call a chicken switch. You just keep your finger on that button and the moment the pressure gets too much for you, release the button and the power's cut off.
Bond: Just like that?!
Goodhead: Oh come on Mr Bond, a 70 year old can take 3Gs!
Bond: Well the trouble is there's never a 70 year old around when you need one...
Your ad here.
2004 National Novel Writing Month winning "The Journal of Alan Ledford" by Roger Ostrander has a similar thought:
"Total destruction the only solution" - Bob Marley
GOOD GOD!!!
"0, Insightful"?
This guy must have had INCREDIBLY NEGATIVE karma to be zero and yet insightful...
No mercy?
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
...or at least have an inanimate carbon rod laying around somewhere.
(source)
"Total destruction the only solution" - Bob Marley
Getting out of bed with 3 broken ribs (all low in front, by where the stomach muscles attach), a sprained neck and 2 bum arms took about 10 minutes each time, for the first month. I healed up just fine, it just involved putting an external fixator on my wrist for 8 weeks.
Check out the life of Dr. (Col) John Stapp, who did all the early NASA high G experiments - he got up to 35 Gs in his rocket sled experiments. Similar injuries to mine, except he had a nice cushy 6 point restraint system, as compared to my 3 point typical car seat-beltt s/content_manager_v02/view_nahf/htdocs/menu_ps.asp ?NodeID=-654157167&group_ID=1134656385&Parent_ID=- 1
http://nationalaviation.blade6.donet.com/componen
..........FULL STOP.
That article should read "20 times the terrestrial gravity OF EARTH".
Right. We don't want to confuse it with the venusian gravity of Mars...
Formula One race car driver David Purley survived an estimated 179.8 g in 1977 when he decelerated from 107 mph (172 km/h) to 0 in a distance of 26 inches (66 cm) after his throttle got stuck wide open and he hit a wall. He suffered 29 fractures, 3 dislocations and 6 heart-stoppages.
"Total destruction the only solution" - Bob Marley
We were recently discussing CT scanners in a class... those things spin pretty damn fast, with all of the electronics experiencing something like 20G's... for hours and hours and hours. And the gantry is these days pretty damn heavy and insanely complex (i wonder how they get the data from the spinning sensors? surely not a million sliprings?) I suppose still maybe MRI is more impressive with its multi-tesla QUICKLY changing magnetic fields.
Well, not to nitpick, but the fastest way to get to alpha centauri (not counting a few out-there theoretical means of travel) would be to accelerate the whole way, and slam into the star... :)
Microsoft has just released their much anticipated hands-free cordless mouse. Warning, it may hurt a little at first.
Good point. We could all use a heathy dose of Grammar Naziism from time to time.
-MJ
Yes, I realize that A/C is a 3 star system...
Microsoft has just released their much anticipated hands-free cordless mouse. Warning, it may hurt a little at first.
Here you go: l :)
You seem to be missing one
"Total destruction the only solution" - Bob Marley
Well, aside from the fact that we're safe due more to the earth's magnetic field (and to lesser extents, the moon and sun's effect on cosmic radiation), we can't REALLY know the effects on the human body until we send somebody outside the relative safety of the earth-moon system. Not to pander to the tinfoil folks, but maybe there's something in our genetic history (panspermia) that provides a defensive reaction to cosmic radiation. I mean, theoretically, the folks that landed on the moon absorbed a lot of this stuff, and are still kicking. Maybe it's good for you, or has a chemotherapy-like effect. :)
Besides, we can barely get to the moon, worrying about how much radiation we can absorb is like being stranded on a deserted island and worrying about the effects of high tension power lines on the human body.
Microsoft has just released their much anticipated hands-free cordless mouse. Warning, it may hurt a little at first.
"Oh, and just FYI for everybody, there is no "acceleration", "pressure" or "force" directly experienced inside a centrifuge."
Yeah there is...
Seriously, I don't hate old people. Just the ones who drive like assholes and never get pulled over for it, but I get a ticket for 5MPH over.
Blar.
Come on guys, are we really that scared of his submissions that we need three tags composed of his name? Why not "centrifuge" or "gravity"?
While one should be skeptical that pressures as great as 12.50G let alone 20.00G would ever be experienced during space travel (space being weightless. . .
How do you suppose one gets to space?
And of course space is weightless. Space is just geometry. It is truely massless. D'oh!
KFG
How about sudden changes in direction?
After going to Wikipedia, I have to say that sitting down does not give 10gs, because right above the data you listed it says fighter pilots sometimes gray out at around 6gs, if this was the case plopping into a chair would be much more interesting than it already is.
Time is of the essence.
;)
On that note, the words "instantaneous" and "sustained" might be of interest to you. You'll find them in any online or offline dictionary.
Isn't it ironic that you call your blog anti-idiots?
"Total destruction the only solution" - Bob Marley
>>Really the best way now to improve the adverse health effects of space travel is to glue their foam on tighter.
:(
We tried that, but they kept suffocating.
Microsoft has just released their much anticipated hands-free cordless mouse. Warning, it may hurt a little at first.
The ultimate plan is to liquify the astronaughts using high G, freeze dry them and send them up in packs of 100 for storage on the ISS. Then they can be work rotated simply by boiling the kettle. Great idea so long as no one mixes them up with the food supply.
-- "Can't sleep, clowns will eat me!"
Heh, let me guess, that book is used as a textbook in university. Otherwise I don't see why it would sell for more than $40. I'm greatly interested in such topics but to feed the money-grabbing textbook publishing machine seems almost tragic.
occultae nullus est respectus musicae - originally a Greek proverb
FYI, I think your sig is missing a crucial comma, without which its meaning is completely reversed. Just thought you'd like to know...
Bonsai Kitten: TNG
"Whoa ... heavy."
"What is this 'heavy'. Is there something wrong with the force of gravity in your time?"
The higher the technology, the sharper that two-edged sword.
No, there isn't.
http://en.wikipedia.org/wiki/Fictitious_force
http://en.wikipedia.org/wiki/Centrifugal_force
l'Homme n'est Rien l'Oeuvre Tout: Gustave Flaubert to George Sand
You experience centriptal force, which is actually a Normal force of the wall of the human chamber experienced on ur body pointed from the wall to the center of the of the machine, assuming u sit facing inward. So there is a force. Welcome to physics 101.
So you see what had happened was....
It'd help with that, too, but other than space combat (hopefully not coming anytime soon) we shouldn't need them.
I am trolling
It's a reference grammar, not a textbook. And that is a fairly typical price for a hardbound book from Oxford University Press.
Wow, now you go so low as to get personal. I knwo what instantaneous and sustained mean asshole, but untill that wikipedia page has sources listed that I can check, I will not agree with its info, because wikipedia has been historicly incorrect many times.
I quote from the centrifugal force article:
"As it is an actual force, it is always present, independent of the choice of reference frame."
The article is wrong. Look up Goldstein's Classical Mechanics (the definitive textbook in Class Mech). The wikipedia article presents an ambiguous definition of centrifugal force (as a reaction to centripetal force). Physicists today do not use this definition (I am one). The reaction to centripetal force is just that. A reaction. centrifugal "force" only exists in the noninertial frame (together with Coriolis and Euler pseudoforces).
l'Homme n'est Rien l'Oeuvre Tout: Gustave Flaubert to George Sand
Oh, and another thing. The force experienced by the fellow in the rotating chamber is generated by some other source (a motor, or gravity or whatever). The fact that this equals
$$
\dot{theta}X\dot{theta}X r + 2 (\dot{theta} X \dot{r}) + \ddot{\theta} X r
$$
is a consequence of the dynamics, not the force. Thus, the centrifugal acceleration is a consequence of the dynamics, not the force, so it's not a force (it's not generated by any of the strong, weak, electromagnetic or gravitational interactions). The normal force experienced by the fellow is generated by the electromagnetic interactions between the atoms of the surface and the atoms of the fellow, but that's not the centrifugal force, 'cause that would exist even if the system was not accelerating (it would be a different value). The centrifugal force (as I understand it) produces a qualitative difference between a rotating frame and an inertial frame (it's not there in the latter), so it's a characteristic of the dynamics.
l'Homme n'est Rien l'Oeuvre Tout: Gustave Flaubert to George Sand
Oh, and I almost forgot, there is no such thing as a force anyway. It's an artificial device introduced by Newton to make the laws of classical mechanics less obfuscated. Ultimately, the most elegant formalisms of classical mechanics (Lagrangian, hamiltonian, and Canonical transformations/Hamilton Jacobi Theory) does away with this "force" nonsense altogether. There are only geometrical and topologocal constraints thatdetermine the dynamics. This is easily exported to relativity, so this formalism's better.
l'Homme n'est Rien l'Oeuvre Tout: Gustave Flaubert to George Sand
Again if I remember my physics correctly, acceleration is a change in speed and/or direction. A centrifuge is a change in direction for sure.
Heroscape, it's like legos combined with anachronistic wargames.
>Again if I remember my physics correctly, acceleration is a change in speed >
>and/or direction. A centrifuge is a change in direction for sure.
Yes, that is true. But, that acceleration is the centripetal acceleration which iscaused by the motor of the centrifuge, not by any nonexistent "centrifugal force" (even if we accept the concept of force, which itself is nonexistent as I have stated in posts above).
In what follows I adhere to the standard definition of "centrifugal" force as the non-inertial force, not as the normal reaction to centripetal force.
The force of the motor gets propagated by Newton's 3rd law through the atomic interaction of the walls of the centrifuge and transferred to the fellow in contact with it. So the force experienced by the fellow in the chamber is the force due to the motor.
The other way to look at it is that there is no motor, but there is an accelerated frame (where the motor is conceptually unimportant as it is outside your universe of the accelerated frame), and you follow an artificial recipe that says that you should just "plug in" (by rote) a force term (in this case "centrifugal force") equal to -mass*acceleration_of_the_frame. This recipe is convenient sometimes, but unnecessary as we can get the same result from ab-initio reasoning as in the previous paragraph.
So what you are doing is assuming that the centrifuge is a different universe, where all physical phenomena are appended by this universal divine "centrifugal force". I dunno abt you, but that's too wierd for my taste.
There is no such thing as centrifugal force. The very idea is completely bogus and unnecessary and so can be removed from all formalisms of accelerated frames without losing any of the physics, so it does not exist.
It's ambiguities like this that proves that the whole concept of force is a pile of rubbish and can easily be done away with (okay, maybe not easily, but the formalisms in classical mechanics that get rid of forces are far more elegant and insightful than all this clunky Newtonian stuff, and).
In case you think I'm being pedantic, I should point out that Hamiltonian, Lagrangian and canonical formalisms are significantly easier to implement computationally in systems where analytical solutins cannot be done (likechaotic systems or quantum systems with multiple nonlinear resonances) because of their logically algorithmic structure, so in the modern world of research, nobody implements all this "force" stuff into their computations.
l'Homme n'est Rien l'Oeuvre Tout: Gustave Flaubert to George Sand
I think that ultimately this is splitting hairs to some degree. I have only a basic understanding of physics, but I think there is a tremendous opportunity for advancement in regards to our understanding of the human body in alien environments (both real and simulated). If we can keep spacefarers healthier by including a centrifuge to simulate gravity it is worth looking at, whether or not there is such a thing as "centrifugal force" (as an aside I believe I heard that the concept was erroneous in Jr High).
I think the original post muddied things up a bit by thinking too much about the extremes of the experimental observations, and it misses the practical applications. The original post I responded to propogated ideas that I don't think fall under the umbrella of physics unless he has heard some very advanced concepts without the basic understanding. I doubt very much that circuits would be impacted by a "force" of 20G for example.
My field is exercise science, so I focus on the human organism. Perhaps there is an application to the instruments and devices that would be used at hypergravity (thus the 20 G stuff in the article), but I find the human element far more interesting, and compelling. I for one would love to see experimental data for a person living at say 1.5G for a two week period, and the impact that the experiment would have on bone density, muscle mass, and the ability of the subject to recover from training bouts. I think a very interesting experiment would be examining training at various multiples of gravity and then recover in zero gravity. If we can find the ideal multiple G training environment with a zero G rest environment we could keep astronauts healthy for the duration of a trip to (and from) Mars.
Heroscape, it's like legos combined with anachronistic wargames.
>I think that ultimately this is splitting hairs to some degree
Well, within the context of traditional Newtonian mechanics, you're right. It's essentially about semantics and interpretations. It gets more complex in more advanced treatments of classical mechanics.
>but I think there is a tremendous opportunity for advancement in regards to our >understanding of the human body in alien environments
I guess that's true. Irrespective of whether centrifugal force is real or not, it is a fact that the adverse effects of acceleration are real.
Science fiction writers like Arthur C. Clarke have proposed a "field-based engine" where, instead of using thrust to propel ships, causingforces to be distributed inhomogenously through atomic interactions (thereby causing all the pressure, G-forces etc that cause people ot die at high accelerations), the engine (or an externalsource) would generate a force field, much like gravity, only more powerful. This would cause all particles to move with the same acceleration, and there would be no "G-forces".
But that is all fiction, in reality, you will have to go through G-forces if you want to accelerate (unless you do so by gravity, but that's rather weak) and so we need to see how it affects us in detail.
I'd mod you up, but I blew all my points yesterday.
l'Homme n'est Rien l'Oeuvre Tout: Gustave Flaubert to George Sand
Didn't they steal this idea from Dragonball Z?
OEÉæÁÄZÝÈA OEÉæé_CX
I thought one of the records set for sustained human Gs was on a rocket sled... Ah yes, Dr. John Paul Stapp.
Ejection seats are another area where people are exposed to high Gs. The Gemini seats were particularly infamous. Both rocket escape systems and ejection seats balance the chance of injury to the crew against the risks of not getting them away fast enough.
Good stuff, as long as I only have to read about it :D
On that very page -- right after the table of everyday G forces -- is a link to a Popular Mechanics article which in turn references "a classic medical study published nearly a decade ago in the medical journal Spine", which most likely is available on PubMed should anyone want to check it out.
Now let me quote from the PM article (emphasis mine):
So, you see, it doesn't matter if you agree or not, those are the facts.I would suggest a more humble approach in the future; there are still people around that can teach you a thing or two, young padawan.
"Total destruction the only solution" - Bob Marley
Interesting table below - showing maximum time at given G levels.
Interestingly, from the second line and below, you're at about orbital speed
at the end of the accelleration, if it's linear.
Summary of Results: (Data primarily from: Bioastronautics Data Book,
second edition, 1973, NASA)
I - Sustained Acceleration
CAPTION: Time vs. Tolerance : G-force limits for reclining subjects
Time (min) Accel Coach (Gs) Water Immersed (Gs)
0.5 23 28
1.0 17 22
2.0 12 17
3.0 8 14
4.0 7 12
5.0 6 9
6.0 5 8
7.0 4 7
8.0 4 6
9.0 3 6
10.0 3 6
You weight a couple ounces more at the poles due to the equatorial bulge. The arctic is at sea level and little more than the antarctic whihc is at mountainous elevation.
Alf (Alien Life Form) came from a planet named Melmac, which is also what it was made of. Too bad everyone turned on their hair dryers at the same time, and the planet blew up.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)