Slashdot Mirror
Origami Plane to Fly From the Int. Space Station
SK writes "The University of Tokyo and the Japan folded paper (origami) plane society hopes to fly a paper airplane from the International Space Station to Earth. The plane will be 30-40cm long and weigh about 30 grams. A University of Tokyo research group has successfully designed a special paper plane model that was able to withstand a Mach 7 high velocity stream for 10 seconds. The experimental plane was about one-fifth the size and withstood temperatures as high as 300C without burning up." Unfortunately for most of us reading this, the original source is all in japanese.
"Check out what I made!"
"Ha, that's sweet! You know what we should do with it?"
*Airlock Sounds*
Obligatory blog plug: http://www.caseybanner.ca/
won't the paper flip when it starts to hit air, and burn up? How do you get a paper airplane to get to mach anything? I know how to make a very fast paper airplane for hand throwing, but it only goes maybe into the low 100 range... I never clocked it, though. Still, I think it would flip before getting that fast.
stuff |
China will probably vaporize it, just out of spite.
Even though it's in Japanese, just use Google Translate to read it.
Somebody gave me an origami book once. I never read it - I couldn't, it was all creased seven ways to Sunday.
It's true I tell you, feller at work's next door neighbour read it in the paper.
Japan wants to fly paper plane from International Space Station to earth:
http://mdn.mainichi.jp/national/news/20080118p2a00m0na025000c.html
I have excellent Karma and I am not afraid to Troll it.
I would think that a metal foil would provide a better "paper" for the plane. Not only would it resist higher temperatures, but it would conduct heat from the hot side to radiate heat on the upper side. Chemically etching the foil on the upper surface to make it black would also help radiate heat. Finally, a metal foil plane would have a higher radar cross-section so it might be possible to track the trajectory and recover the plane.
If purists insist on paper, the one could deposit a thin foil veneer on the leading edges or deposit a trace-work of metal to create a reflector of radar waves (extra credit for adding an RFID chip to the mix).
Two wrongs don't make a right, but three lefts do.
What if it crashes? All the boffins are gathered, scratching their heads, and then one of them will say "But it looked fine on paper!" Then all the others will groan, and proceed to calculate the optimum method for beating the crap out of him.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
This is the Librarian wing of the JSA testing new paper for books. This paper, obviously with embedded copy protection coatings, will prove that books are better than websites, and gloriously launch the Japanese people to a state of technological superiority over western libraries. This is just stage one of the Paper Ninja Warriors contest.
Stage two involves plasma thrusters and a "paper moon" orbiter. When you can afford to launch 14 million orbital vehicles, one of them is bound to accomplish the job. Besides, what better building material to use if you want to send a message to aliens in other galaxies?
Support NYCountryLawyer RIAA vs People
... i can think of much better ways to spend money.
Better ways for *you* to spend money. I personally would spend quite a lot of money to be able to drop a paper plane out of a space station.
This is brilliant! The use is obvious. We need cheaper reentry vehicles. These vehicles would not be designed to bring back passengers, but there are times when you have 50 (harmless) samples and would like to get one of them to a lab earth-side.
First, for those who say they've never seen a paper airplane break 100MPH, that's at 1 atmosphere. Mach 7 is definitely not at 1 atmosphere.
Second, for those who say it would flip, try writing a stability proof sometime. do you know how to apply inverse kinematics? can you write an equation for the Jacobian of a human elbow joint?
Third, the first step is to try one small paper plane. It'll probably not work, and we'll have to try again. Eventually, we might get a working 8" plane. Some day, we might even have a meter long plane that can bring 3 ounces back to earth.
Imagine an astronaut who is sick, and we need to get some lab tests run. Sending a shuttle or Soyouz down is incredibly wasteful. OTOH, a paper airplane could be equipped with a tracking device (think 1-2oz GPS & transmitter) and a small sample case. We drop the plane, and it's got a 1-in-3 chance of getting the sample into the right hands, in a usable condition. So we drop 5 or 10 and hope for the best.
Think of the potential when we start building larger stations & craft in space. A line of bolts could shear off, and we might not have the ability to analyze it in space. We drop one on each of 5 paper planes, and get a good idea from 2 that we recover of what happened. Were the bolts defective? Was it a fatigue issue? Were they improperly installed?
Imagine a very low cost mission to a near Earth crossing object. Half a dozen paper planes could let us get a few ounces of samples on the cheap.
Andy
The ISS Orbits the Earth at around 7.400k/s at an altitude of 365k. You can't just throw something out of the ISS and hit the Earth's atmosphere for Re-entry. If you "throw" it out of the ISS, it'll orbit, just like the ISS. In order to intersect with the Earth's atmosphere for areo-braking, you are going to need to lower he perigee of your orbit to at least 50-60k. You'll need a delta V of about 100 m/sec to do this.
What gives? Have they built an oragami retrograde rocket as well?
I'm not associated with the project, but I do have common sense.
For those who think this is a high-risk project, risk is the chance of failure multiplied by the cost. The cost of throwing a paper plane from the ISS is low compared to other experiments, and we will learn quite a bit, not matter what happens.
For those who think this is a waste of money, I understand. You would have never funded the research into better clocks that eventually led to better navigation, which led to Columbus' voyages. The idea of opening a new frontier does not excite you. You would have us turn inward like the Chinese did at one point, burn your own ships, and never venture out again. You will accept a stagnant society. Based on my understanding of you, I offer one suggestion: Please commit suicide. We're better off without you.
Andy
Go creased lighting! Go creased lighting!
So, here's the thing. I've got a plane. And I have a window in the plane. The rules say (FAR 91.15) that I can chuck stuff out of the plane if I take reasonable precautions to avoid hurting anyone on the ground. So the answer here is simple:
A bunch of paper airplanes with japanese writing on them, air brushed lightly at the nose to look like it's re-entered.
Thrown out the window over the local university.
Playing the odds, at least one of them will be seen landing by someone who reads slashdot. "Holy crap!" he/she (just kidding, he) shouts.
Mua-ha-ha-ha.... I don't know what step 2 is, but #3 is profit.
Fuck you, scissors and rock!
I think the odds are against ever finding it. You might need to launch a hundred to have a decent chance of actually having someone find one.
As a rocket scientist, I'll take the reins here.
From the altitude the ISS is orbiting, there's no such thing as approaching the atmosphere "slowly". The ISS is traveling at about 17000 mph around the circumference of its circular orbit. In order to enter the atmosphere, a body in that orbit would have to slow down in order to enter an elliptical orbit which intersects the atmosphere. This requires a velocity change (delta v) of about 200-250 mph. Even with that change, you're still traveling at 16,750 mph, so that when you finally do hit atmosphere, the friction from the air will be very high, even if the air is thin. As the friction slows you down, you drop farther into the atmosphere, where the air is thicker and there is more friction. These two changes (air pressure and velocity change) work together to reach a point of maximum heating, and then taper off again as you reach subsonic speeds. The steeper the dive, the faster you reach thicker air, and the higher the max heating point will be.
Let's say for argument's sake that you wanted to drop straight down from where the ISS is orbiting, with no horizontal velocity. (That would require an instantaneous delta v of the whole 17000 mph, which is nigh impossible, but we'll assume we can for our thought experiment.) Since the ISS is orbiting at an altitude of about 225 miles, and the atmosphere is generally considered to start at the 62 mile mark, that's still 163 miles of vacuum free fall to contend with. Leaving out the square-of-the-distance effects of gravity fall off (which are close to negligible at these distances), we get a fall time of sqrt((163 miles)/(32 feet per second squared)) = 164 seconds. That gives us a velocity of (32 feet per second squared)*(164 seconds) = 5248 feet per second, or 3578 mph at the moment we hit the upper fringes of the atmosphere. The heating will certainly be less than the standard deorbit, but it is still a decent force to be reckoned with. Any angle larger than the vertical will require a smaller delta v but will result in a higher entry velocity and higher heating.
Now you might be thinking to yourself, "but AeroIllini! You totally contradicted yourself there!" I did. Except that as you vary the angle of entry from shallow to vertical, the graph of max heating reaches a peak and then falls off again. So for a very shallow entry, your heating will be lower than a steeper entry, but going even steeper the heating will taper off again until you reach vertical entry, which will have the lowest heating of all. Vertical entry also has the highest delta v requirement of all, and a shallow entry has the least delta v required.
I hope this answers your question.
For security, the MD5 hash of this message and sig is 09f911029d74e35bd84156c5635688c0.
I preferred the google translation.
>Land in the world where you do not know the fairy who could deliver" a dream said.
Milton couldn't have said it better.
Open Source Drum Kit, LPLC deve board - mjhdesigns.com
Don't underestimate the power of pure curiosity. Maybe launching paper airplanes from a space station isn't directly going to contribute to anything great like curing cancer, but when that great thing does happen, I'm certain that the big leaps are going to be made by people that just followed their curiosity, instead of worrying about the significance of what they're doing.
As an example, Richard Feynman had sort of a breakdown early in his career. His inspiration had run out, everybody was waiting for the genius to do something brilliant, and he was feeling miserable. Then he decided that he wasn't going to care about people's expectations, about what kind of research was respectable, he was just going to follow up on the little things that interested him. He sat in a cafeteria, looked at a spinning plate (I don't remember the details, there was a spinning plate somehow) and he decided he would try to figure out the forces that made that plate spin like that. He did figure it out, proudly showed it to some senior, who said 'great, but what's the relevance'. There wasn't any, he'd just followed his nose, and solved a problem. Later that little solution turned into to the research that earned him a Nobel prize and became the most accurate scientific theory to date (or second most accurate, I'm no expert).
The point is that many scientists don't work well on something that is prescribed in any way. They need absolute freedom to just do stuff that interests them. If they really have to they can work on things that are more immediately relevant, but not with passion, and it'll never be as great as the stuff they do when just follow their instinct. And these scientists tend to be the ones that come up with the great breakthroughs.
So if these guys want to send up 30 grams with the next shuttle, and take up three minutes of the astronauts' time, I'm fine with that. It's important in a subtle way. It's also very cool.
If you can track it, you can learn stuff about the reentry characteristics of ultra-light probes.
Now, think about the consequences of that for a moment. Most existing reentry vehicles are reentry vihicles designed to return personnel and equipment and data to ground level, but when you explore other planets the data flow goes the other way. There's also a lot of data that doesn't have to be collected from the ground. So, instead of an orbiter chucking two or three big chunky armored landers which attempt to survive crashing into the surface, and then trying to get a rover to crawl out of the lander and chug for miles to get somewhere interesting (without falling down a hole), why not release a cloud of ultralites and have them beam back picture info and data as they they drift earthwards? If you could insert an ultralite robotic aircraft into the atmosphere (of the type they currently use for weather sensing), it wouldn't have to land, and some of these designs might be able to stay aloft for years. Couple that with a microsatellite relay network and you potentially have a good system.
Alternatively you could go down the balloon path ... instead of a conventional balloon carrying a heavy heavy metal box with electronics in ... instead, stick your CCD chips to the balloon, print additional circuitry and perhaps solar cells directly onto the surface, perhaps use the upper and lower surfaces as charge carriers to avoid batteries, or have the lower surface metallised and the upper transparent, and use it as a solar collector.
With a whole bunch of these balloons drifting about in the upper atmosphere, you have an ad-hoc signal relay system. Hell, give em internet protocols. You won't be able to steer them, and you'd always be losing contact with a few, but a mission could carry along hundreds of them. The transponders would only have to be comparatively short-range, maybe you could even beam power from the orbiter. If you want random mapping plus a study of the atmosphere, bung 'em into a low orbit and wait for them to decay.
Perhaps a future Venus mission might well involve an orbiter repeatedly chucking a series of fifty cheap, disposable, "smart" transponder-equipped paper planes into the Venusian atmosphere and relaying that data back to Earth.
The first step is developing and testing materials. The second is using a tracking system to see how well they cope with reentry. The third is embedding smarter electronics.
Eric Baird