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part 2 the boring mechanical nuts and bolts.
Starting with the room described in part 1 bellow, it would need to be enclosed in some sort of support structure. On the north and south sides of this, will be mounted bearings A & B the function of these bearings is to keep the room in the correct
orientation, floor down, at all times. Bearings A & B are mounted on the travelling end of a short arms. These arms are mounted on bearings E & F, these arms are spun sufficiently fast to produce 2 G of centripetal acceleration.
Taking the situation as the room passes over the top, at the level of bearings A & B there will be 2 G of centripetal acceleration acting upwards and 1 G of gravitational acting downwards, leaving a net upwards accelerated of 1 G.
to complete the mechanical aspects of the design. The arms would need to be split in half, by bearings C & D. The outer part of the arms will be rotated about bearings C & D at the same speed as the inner part of the arms,along with bearings C & D, are rotating about bearings E & F.
Taking the situation as the room passes over the top, both halves of the arms will be pointing in the same direction, up. Half of a turn later the inner part of the arms will be pointing down. however the outer part of the arms will have turned trough half of a circle, and will now be pointing in the opposite direction to inner part of the arms.
So half a cycle after the top,where the rotary motion adds 2 G of acceleration, bearings A & E and B & F will be lined up. So at this point the only force is gravity. The path that will be traced by bearing A as it travels through one cycle will be an up side down rounded hart.
part 1 practice & principal.
This idea started life as a training aid for astronauts. But I think it will inevitably end up being hired out as a bouncy castle for adults. So thats the idea, let NASA use it for dull work if they want.
Imagine 2 to 10 adults in a room that has; ceiling, floor and walls made out of strong trampolines The junctions between surfaces would need to be well padded to prevent injuries. The light would have to come in through the fabric of the trampolines
At the start the people would be clustered together, because the floor would be depressed in the middle. As the gravity is apparently turned off, they would seem to get lighter and the floor would level up. At some point someone would feel light enough to fly, and would jump up to the ceiling This would knock everyone else of their feet. They would over react instinctively, kicking themselves into the air. There will follow a period of adults bouncing of the walls like hyperactive 8 year old s Or trying to sit on the ceiling, not easy when people keep bouncing off it. Eventually someone would bump into someone, or grab someone, or find themselves in an interesting position, and the mood would change
The principal of operation. No magic is allowed Gravity acts downward with a force of one G, at all points, all of the time.
There are two states to the device. A / Normal, gravity = 1 G down. B / Driven = 2 G of upward acceleration minus 1 G of gravity down, = a net 1 G upward force. By switching between these two states more rapidly than the body can be accelerated in either direction the illusion of weightlessness can be created.
[ edit / Ideally the arms should be kept as short as possible and spun fast. Large masses in high speed cyclical motion can cause problems. This dose not rule this out, as impossible, it just means that it would be difficult to do.]
If anyone can do calculus. How fast would the switching need to be to keep the movement down to less than an inch? I reckon it will be about 1/256 of a second. And that a frequency of 1 kHz will be about a 1/5 of an inch of motion. But my maths is fallible.
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State A: the device is at rest.
State B: the device is accelerated downwards at approx. 20ms^-2 |
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If you alternate these states with equal time given to each, then the net effect is that the device is accelerated downwards at approx. 10ms^-2, i.e. it is in free fall. |
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So what advantage does all the vibrating have? |
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//A / Normal, gravity = 1 G down.
B / Driven = 2 G of upward acceleration minus 1 G
of gravity down, = a net 1 G upward force.// |
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Upward acceleration produces the same feeling as
gravity. Therefore this alternates between 1g
down and 3g down. |
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If you meant the other way around, it alternates
between 1g up (downward acceleration) and 3g
down (upward recovery stroke). Net effect is still
1g down. |
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[Marked-For-Deletion] Bad Science |
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//more rapidly than the body can be accelerated ...
If anyone can do calculus.// Res ipsa loquitur. |
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The astronauts in the US are standing in the unemployment line these days... |
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//But my maths is fallible.// Rem acu tetigisti. |
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At best, the occupants will experience an illusion of weightlessness similar to that experienced by peas in a maraca. At least your OrGy won't need a separate vomitorium. |
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Are you sure you mean vomitorium? |
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I suppose, the idea is that the participants will never wish to leave all at the same time, since they are having such fun? |
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I could have meant that there is no need for gladiators to come out and lay into everyone because there would be plenty of bloodshed and mayhem anyway, but instead meant a room to vomit in, because I just felt like being wrong for once. |
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// I just felt like being wrong for once // |
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We feel obliged to point out that that's not actually a precedent. |
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//that's not actually a precedent// Are you saying that I'm not going to feel like being wrong again? Or did you mean "that's not actually a first"? |
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You can't oscillate it at that speed - the stretch of the fabric will dampen it out, and the average will still be 1G. |
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2 to 10 adults inside of a speaker, operating somewhere between 250-1000 hz, at something over 160 decibels? |
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The seismologists use the term "liquifaction". A mechanical engineer might say "pulverized", while a layman with a good blender might opt for "purée". |
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The attorney would simply term it "first degree murder". The defendant's barrister, however, would counter, "But it can't have been pre-meditated - it's obvious [j paul] never thought this through!" |
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But would the resultant goo be suspended? Surely if
the body bits were small enough, they would form a
mist floating in the air and the dream of microgravity
simulation would have been achieved? |
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Not my type of orgy. I don't think I would want to blend in. |
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What if it were also evacuated? |
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[MechE] This isn't bad science. It's just a resonate trampoline driven by an oscillation of the floor rather than by legs. (With some implied sexual activity at random intervals.) The math goes badly wrong, however. The switching needs to be on the order of seconds, not milliseconds. Otherwise the occupants will be standing on the upper stroke position of the floor, and will have the unpleasant sensation of standing on a buzzing surface rather than floating. In which case the floor is accelerating up and down, but the occupant's body (except for the soles of his feet) is experiencing normal gravity. Vibrating feeders and hoppers work this way. They vibrate particles into a semi-levitated state, sometimes imparting a sideways motion to move them where they're wanted. The particles don't float off, however. |
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Vibrating feeders work this way, but they objects do not experience zero-gravity. The experience a repeating series of impacts that average out to one g downwards. If the frequency was just right, a standing person would, feel a series of 2-3g impacts on their feet with alternating brief periods of zero-g. Givent that it is specified to be fast, the rest of the body would experience a standard 1 g. (And flattened arches, broken bone, etc, etc.). |
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[MechE] A bad science MFD is generally reserved for something really bad at the core of an idea, not something that doesn't work as advertised or has some terrible fault (like broken bones), otherwise, most everything on this site would have to be deleted. |
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This is intended to produce a zero g experience. It doesn't,
because the basic concept is flawed. That's what gets the
bad science mark. If the concept were valid but the
excecution flawed, then I would agree with you. The whole
broken bone thing is secondary. |
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//but they objects do not experience zero-gravity// |
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In fact, they can experience free fall, but just for short periods. So there's no bad science, just bad engineering. |
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If the frequency is considerable lower than mentioned in the post, they will experience free fall for brief periods, but no different than jumping in the air. Given that this is supposed to be conceptually different than that... |
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Let me start by thanking every one for some thoughtful and amusing annons I was afraid that you might not touch an idea in two parts. The reason for doing it that way was that I was hoping that some one would have come up with a better way of doing it. Because my idea of using an eccentric centrifugal force as serious short comings, not described above. |
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pocmloc Not the floor dropping, but occupants being flung away from the centre of rotation. |
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MechE Part of the reason for the two part submission was to try to separate my flawed design from the scientific possibility. -2G + 1G + 1G =?G. My design only manages this along the line between bearings A&B. |
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mouseposture You know I have not mastered English yet, so I willn't have a chance if you are going to use Latin. |
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xandram An other reason for not trying to sell the idea to NASA. I gather that the Indian space program is still flourishing. I wonder if there will be a brain drain? |
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spidermother Of course it will need a vomitorium! People will need somewhere to take their shoes off before they are allowed on the trampolines. |
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On a more serious note. With the direction to the floor always being down, but with gravity apparently continually changing, in both direction and strength, someone is bound to
......... |
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Im thinking more, Gladys ate her, than gladiator. |
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Ling The soft walls are there so that I dont have to use the defence that lurch as so amusingly layed out for my. |
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nineteenthly unfortunately not. There will be a small //gravitational field down// to four of the six surfaces. |
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If it is evacuated, then that definitely excludes any sort of orgy. |
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I would like to see a diagram. I'm still pretty sure
this can't work on principle, but the mechanical
description is unclear. |
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// If it is evacuated, then that definitely excludes
any sort of orgy. // |
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I don't think so. If we're thinking of genital contact
between people, there just need to be suits with
docking points and airlocks. The parties - actually i'll
post this. |
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What are the limitations on what can be posted? |
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Iv not seen any really clear drawings here yet, but then I am still fairly new to the HB. |
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Ive just reread the help file.
To help people to visualize this.
1) Start with bearing E, with rod 1 above it, pointing up. A curved arrow to indicate that rod 1 is turning clockwise. On the other end of rod 1 is bearing C, with rod 2 also pointing up, turning clockwise around it. And on the other end of rod 2 is bearing A. a small house symbol could be used to indicate the room, always the right way up. And most importantly an arrow leaving bearing A pointing away from bearing E. this indicates the scale of the centrifugal / centripetal force throwing things away from bearing E. For the sake of this image make it 4 units long. 2 rod lengths from E and 2 units of rotation about E.
2) Moving on a quarter of a revolution Rod 1 is horizontal and to the right of E. Rod 2 points vertical down. The house symbol should still be right way up, but the arrow pointing away from E will have shrunk to 2.4, 1 unit of rotation around E and 1.4 units distance from E.
3) A quarter of a revaluation later, bearings A & E are in line with each other, so there is no force being generated by the rotary motion. |
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A different way to visualize this, that might make it more obvious / intuitive. |
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Imagine standing on the edge of a childes roundabout, in a play ground whilst it is being spun really fast. It will feel to you like you are being thrown out over. Note that is not a feeling of being pushed out, but more of a feeling of falling / flying out. |
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Now imagine an identical roundabout mounted on top of the first one, with its centre at the edge where you had previously been stood. Standing on the edge of this one as it goes round, you will move between standing over the top of the centre of the first roundabout, and a position two roundabout radii from that centre. |
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As seen by someone on the climbing frame, with both roundabouts turning clockwise at the same speed. as you are moving out to the point furthest out, both motions will be moving you in the same direction, left to right. The distance between you and the centre of rotation is long and as a result the outward force that you feel will be large. half a revaluation later, the first roundabout is now moving right to left, but the second one is still moving you left to right. The result is that you are moving much slower as well as being closer to the point about which the roundabouts revolve relative to the playground. So you feel less force. |
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If you have got this image, turn it on its side so that the maximum force is strait up and twice as large as gravity. |
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or a giant hamster wheel. |
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You completely replaced the original idea with a different one. That makes the annos totally irrelevant. If you want to do that, delete the entire idea and start over, don't hijack everybody's stuff and make them look foolish. |
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The shape produced is a cardioid. The equation is
r(theta)=1-sin(theta). I don't deny it will produce
a brief free fall as the person falls towards the
origin. It will then produce a very rapid shift to a
2g force back out. Net result, the person still
experiences an average of 1g. |
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Per the earlier discussion, if this is fast enough,
the person might only feel the average 1g, but
most likely will end up with shattered feet. |
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I've read this all again, very carefully, including the new
material, and... |
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It's not so much that I don't get it, but that I find myself
wondering what's there to be got. |
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Would these be, er, nekkid people? Hence the name? |
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This reminds me of a technology for growing bacteria in
effective zero gravity, without having to leave the ground.
It's a device that repeatedly bounces the bacterial culture
up into the air, so it spends most of its time in freefall. The
acceleration of the bounce is too short for the bacteria to
feel it. Obviously this would not work in your application. |
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