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Space Station Solar Equipment Showing Damage
bhmit1 writes "The latest space walk has turned up some bad news for the problematic solar panels: metal shavings. From the article: "The rotary joint, 10 feet in diameter, has experienced intermittent vibrations and power spikes for nearly two months. Space station managers were hoping a thermal cover or bolt might be hanging up the mechanism. That would have been relatively easy to fix, so they were disheartened when Daniel Tani radioed down that metal shavings were everywhere. 'It's quite clear that it's metal-to-metal grating or something, and it's widespread,' Tani said.""
That's not metal-on-metal grating in the bearings, that's just some sick bastard playing Yoko Ono.
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
Oil does not work in space. It either freezes or evaporates. In fact only some "solid lubricants" like graphite and MoS work to a point.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
It's one thing to get the metal on metal thing going in your car and then be stranded alongside the road. But at least your life would be in no danger. It's quite another to get the metal on metal thing going and getting stranded in space. Tow trucks for space stations cost a considerable amount more. And the mechanics... don't get me started on the mechanic's wages.
The game.
...or something.
Thanks for the technical breakdown. Sounds like the way Beavis would describe it. That's comforting. Or something...
That's a joke but it's a good point. Why not cover the panels with a coat of mobile 1 or some other high end oil. Then whatever hits the panels will be less likely to cause damage. It'll slide on by so to speak.
I would think the chance of dust building up in the oil could be a problem. It might need a windshield wiper and a sprayer to change the oil.
Get a big magnet...
All that rocking of the cabin during 'sleep' hours is taking its toll!
I noted that they intend to fit a replacement joint, and are limiting the travel of the solar panel(s) in the mean time. My question is, do they know what the source of the problem actually is? Is it a manufacturing defect, damage or wear and tear in the currently fitted joint? If it is, replacing it is a reasonable solution. But if it isn't - i.e. if there's a design or operational problem - replacing it will just be a temporary band-aid, and the same thing will happen again sooner or later.
Ever since a few people died, the media will report on any damage on any mission. This is normal.
it's not a money sink, it's an excellent learning oppurtunity. So the science it promised hasn't come around, but we're figuring out how to live in space with this project, and considering that we want to start sending people to mars, back to the moon, and various other projects, I think it's a good thing the ISS is up there.
I'm god, but it's a bit of a drag really...
Towing in space has been done before. Grumman sent North American Rockwell an invoice for towing their crippled spacecraft home. The rate per mile seems pretty reasonable too.
All joking aside, this is going to be a bear to fix. The best scenario would be that the drive gear was munching an insulation blanket. The debris would be friendly to space suits, and should only be labor intensive to clean out. If the gears are grinding on each other, the debris will be sharp and hard. That would be "bad" and I'd expect NASA to seriously consider returning the entire assembly to earth for repair. Expensive, but much less likely to kill someone.
I'm of the opinion that the drive system on this beast is probably over-engineered. It should resemble a Ford F-150 differential - loose tolerances, and designed to run for many millions of rotations without much maintenance. There's absolutely no need for the solar array to have precision pointing capability. I really do hope that the problem isn't due to over-engineering, but I wouldn't place a bet.
I was gonna suggest using a dustbuster to sweep up the shavings... but there's nothing to suck...
Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
The Beavis version would be more along the lines of... "Uh huh, huh huh huh, uh huh, or something... I am CORNHOLIO! I need metal shavings for my bunghole! Bungggghoooole! Gagagagagaga. I have no bunghole! Or something."
The game.
SJW: Someone who has run out of real oppression, and has to fake it.
"Wow," said his spacewalking partner, Scott Parazynski. Its nice to see those "Keanu Reeves Linguistic School" classes paying off for astronauts.
Mit der Dummheit kämpfen Götter selbst vergebens
heh
Even if we just assume they know so much more (which certainly used to be true in the past when they basically had the monopoly on staying up there long-term), the answer is: depends.
Globally, for the world as a whole, sure. Locally: no. If you never do it yourself but always ask the others they will get better and better, and you'll depend on them more and more. That's specialization all right, and according to economic theory that's a good thing. You just have to make sure you have something of equal or greater value to trade with... because if you don't, and I'd say in the foreseeable future there won't be many things more high tech (and therefore potentially valuable) than space-faring knowhow, you are screwed. Unless you believe that human nature is going to change completely.
(I welcome the language patrol but this time I'm ahead of you ;-) )
./ (but as I said, I don't complain or mind, but maybe some moderators do who - rightly - mod this "offtopic")
I should have said "had been on a horse before", not "have been". I wouldn't add yet another post if I hadn't had relevant experience (with getting corrected) before at
Opening this thing up would be something like trying to rebuild an Automatic Transmission, then add the complexity of doing this in micro-gravity. It would probably be easier for NASA to send up a complete replacement instead of trying clean out all of the metal shavings and replace the parts that are damaged.
Homo homini lupus
If you coat the solar panels with oil, then you're going to be reducing their efficiency because the photons from the Sun will have additional media and boundaries to get across... more opportunities for reflection & absorption to take their toll. Also, according to a previous post, traditional oils as you and I think of them wouldn't work in space, because they'd freeze or evaporate. Nice try, though.
"It's quite another to get the metal on metal thing going and getting stranded in space"
They have spares on board. Excepting the fact that it came as a surprise (a similar setup is ok), this is a non-issue.
Come on now, we all know Jap cars are the most robust and maintenance free.
http://www.youtube.com/watch?v=Lrk6vsb77xk
Sure you have to do things yourself occasionally, but there's nothing wrong with learnings from others too.. if you tried to play golf or an instrument without any lessons, then you'd be missing out on hundreds of years of experience and little techniques that could help you play/sound better. Just a silly example.. I get your point though, if you just mooch off of others then you lose the ability to fend for yourself.
which is totally what she said
I think that was his point. That the F-150's differential is NOT over-engineered.
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
over-engineering doesn't mean tight tolerances or precision parts. It means you just spent 3/4 of your budget to go from 95% accuracy to 96% when you only needed 95%.
Yeah I should have known that. Check the username, it's my job.
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
Someone must remember the Asimov story about the space mechanics sent to check out some satellite and inside they find some kind of metal worm burrowed into the thing.
Metal on Metal grinding? Or have we been found?
-- taking over the world, we are.
They supplied part of the computer system and the O2 Generator.
In addition, they have never done anything near this big. As it is, the ISS is already double the mass of MIR, and it will go up by 50%. In addition, it is about 50% more living volume than mir and will still double over the next 2 years. This is WELL beyond what russia has done. This is all an new learning experience for the world. Fortunately, this experience will enable us to go to the moon and mars a lot cheaper and faster.
Heck, look at China. Their space program is now outspending yearly what Apollo did at its' height. And with that, they launch a fraction of the flights that did and currently do. That is because they are busy trying to acquire the same technology (generally buying it from Russia or simply stealing it from NASA and RSA).
I prefer the "u" in honour as it seems to be missing these days.
we should send up some republicans and/or neo-con ministers and then listen to the toe tapping and doing drugs all night long? No thanx.
"Try and fail" can be a bad approach when you're dealing with the space shuttle, which is simultaneously the least reliable and most expensive option.
Another option would have been to bring back the Saturn V, which despite having 10 times the payload capacity of the shuttle, costs less for a single launch. We could have had the space station built long ago for much less cost if we weren't so hell bent on using our space shuttles for everything.
God I want to mod you up NC buddy, but you're already at 5 ;-)
"...twenty year old piece of machinery needs upkeep."
In other "news", What is now a supercompuer will fit in your hand in a few years. Researchers achieve amazing memory density. And so on.
What would be news (for nerds, stuff that matters) would be "aging solar panels repaired, here's how they did it", "Researchers build supercomputer out of 1,000 networked cell phones", or "new memory device with no moving parts has greater capacity than the largest hard drives and can be manufactured for twenty dollars per unit".
Wake me up when there's something to see here and I can stop moving along.
-mcgrew
mcgrew's razor: Never attribute to stupidity that which can be explained by greedy self-interest
Ya know, a metal shaving, released from a Chinese satellite (with a Clinton-Gore'94 bumper sticker) moving at 17,000mph or more is a cheap way to supress satelittes, and, it's been done before. I hope it's just the wearing of a part, and not the start of an orbit-war.
--- For a good time mail uce@ftc.gov
I didn't know the ISS had such a big despun platform. On uncrewed satellites, despun platforms have historically been a source of catastrophic failures. If the bearing suddenly locks up, the whole satellite starts spinning wildly out of control. I assume the ISS wasn't designed so that the failure of this bearing would kill eveyone aboard, but then what does happen if it fails? The article in today's NY Times says there are backup motors, but how does a backup motor help you if the bearing completely seizes?
Find free books.
Correct on the oil. The article also mentions about micro meteorites damaging the rails. They also really need the technology for some kind of a force field. Anyone know of any work or research or how long?
Shoot, I even have a spare Ford 3.08 ratio differential. NASA can get it off me for what I paid for it, or I'll even give it to them if they let me do the installation ;)
I'm surprised they're not using a magnetic bearing, considering the size and relative lack of graviational stresses. If it was properly thermally managed it might even be possible to make it superconducting, but maybe that's a stretch.
Random and weird software I've written.
Now that's what I call a galling problem.
Don't you think it'd be better if there were several ISS's up there? Because for the amount we spent on this one, we could have have two or four more up there. While redesigning the system so that the Russians ended up on the critical path was remarkably expensive and stupid, we also have a dependence on the Space Shuttle which costs $2 billion per year even if nothing is launched (as was the case from 2003-2005). And currently the projected ISS costs are somewhere over $1 billion per year. I occasionally hear claims that by the end of its guaranteed lifespan in 2016, it'll be over $2 billion per year. My take is that NASA could have done a lot better by scrapping the Shuttle way back in the early 90's, never building the ISS, and instead work on encouraging commercial launch vehicles in the 25-50 ton range.
Since what is done is done, I think the next best strategy is to complete the ISS as soon as possible, phase out the shuttle, and switch to commercial launch vehicles like the EELVs (Delta IV heavy and Atlas V heavy) for near term space development goals. In 2016, I can see the possibility that the ISS survives, namely, that the cost of a replacement is high enough that it is better to keep the ISS with its heavy maintenance in orbit. But that doesn't seem likely. I think by then we'll be able to replace most of the functionality of the ISS for the cost of a few years of maintenance of the ISS.
My take is that the number one lesson of the ISS is that it was a huge money sink. If you ignore that it took more than $50 billion just in US spending to put it there and maintain it till now, then you are ignoring the biggest lesson of all.
These *were* designed to run for many rotations. The design specs for the SARJ (Solar Alpha Rotary Joint) were that the 10.5'x2.5', 2,500lb structure would rotate at 4 degrees per minute without imparting vibration to the laboratories that would mess up the microgravity experiments, for a minimum of 15 years. They also have to transfer 60kW of power at 160V while rotating through a "roll ring". These were the design specs, and they were engineered around that; this break was not supposed to happen. That's why this is considered an anomalous event. It's not a case of an insufficient design goal.
One thing that a lot of people don't realize is that there's still a tremendous amount of stuff that we don't know about living and operating things in space. It's deceptively similar to our world; just picturing it being like an Earth where you can't breathe and you can have enough velocity to fall in a circle simply doesn't cut it.
Example: TSS-1R. Space Shuttle Columbia deployed this as part of NASA's series of experiments with orbital tethers (for "hanging" craft from other craft and for raising and lowering orbits). When the tether was 19.7km out of the desired 20.7km deployed, it snapped. Evidence suggested arcing and burning in the tether. Why? The tether was at -3500VDC compared to the orbiter, with no current flowing through it. A minor defect in the tether's insulation left the conductive core exposed to space. Unexpected trapped gas in the insulation bubbled out in the vaccuum of space. This gas created a path for conduction to the orbiter, creating a plasma arc that burned away at the tether until the remaining strands failed under the strain.
In hindsight, it's easy to look at this and say, "Oh, we should have had a short-detection system." However, hindsight is 20-20. We've learned a great deal from past experiences, which unfortunately means that systems have to get more complicated. For example: where does the heat from running the drive motor for the arrays go? Why, it goes all over the place! It took an entire design study just to figure out where it would be going and what to do with it. Now picture unexpected current draws (creating more heat) from the metal shavings thrown into the mix, and what that will do for heat load, or what the metal shavings themselves could get into or allow to conduct unexpectedly. Things get tricky fast.
Too many people seem too eager to see a "finished product" in space. It's important that things like the ISS be seen foremost as learning experiences. In this case, I'm sure we'll see the same thing.
"We consider that six courts and an asylum claim are a rather odd way of returning to Sweden within a month."
Reduce, reuse, cycle
This might be a good time to try a small robot. I am guessing that a bolt came lose and is getting ground up. It may be possible to send a small robot up there, inspect it, and clean it up. I just wonder how far along the robotic tech has moved
I prefer the "u" in honour as it seems to be missing these days.
Even on rough vacuum systems here on good old terra firma, you learn that in a vacuum system, damn near everything evaporates. Even the special 3M vacuum grease evaporates, just that it does it slowly. Throw in some pretty damn low temps when you're not facing the sun and you've got even more problems trying to get stuff to work. Than again, the folks at NASA do have the experience and the equipment to test stuff like this http://www.nasa.gov/mission_pages/constellation/orion/vacuum_chamber.html.
Okay..I'm going with the obligatory Armageddon quote: "American technology, Russian technology, what's the difference? It's all made in Korea!" Send up a crazy Russian mechanic and a wrench to beat on the equipment with...problem solved. :) Aside from that, I used to work with the space station program...these things ARE overengineered...but made by the lowest bidder...btw, the space shuttle seats rock. :) Only the commander has power seats. :)
Remember, it's not paranoia if they really ARE out to get you...
God, can we just de-orbit the waste of money ISS and spend the money on real science already? Also toss out that turd space shuttle program and make some decent vehicles.
On the other hand we do know a great deal about people and I'd bet that NASA is rife with cronyism, nepotism and patronism. Looking at what progress has been made, personally, I'm completely disgusted by how little we've accomplished in space.
Space travel, the trial-and-error way, eh? You mean, Wan Hu style? ;)
"Early in the sixteenth century, Wan decided to take advantage of China's advanced rocket and fireworks technology to launch himself into outer space. He supposedly had a chair built with forty-seven rockets attached. On the day of lift-off, Wan, splendidly attired, climbed into his rocket chair and forty seven servants lit the fuses and then hastily ran for cover. There was a huge explosion. When the smoke cleared, Wan and the chair were gone, and was said never to have been seen again."
Dunno about you, but I'd rather have it designed by the kind of people who'd rather sit down and calculate, instead of just doing the first dumb thing that comes to mind and see if it works.
Yes, _sometimes_, for a very narrow class of problems (like counting the bytes) the simplest way is to just do it and measure the number. But when you actually have to design something more complex, that quickly becomes a horrible idea. Even for something as simple as a watch, the probability to get it right by just throwing some parts together repeatedly and seeing if the result works, is close to nil. At some point you have to sit down and calculate the size of those cogs.
Plus, there is a lot of other stuff around you that happened only because someone sat down and calculated stuff, instead of good ol' dumb trial-and-error.
There's no way to invent a laser by trial and error, for example. The probability that just accidentally you'd have the right kind of material, and the right kind of coating at the ends, and the right light wavelength to excite it, and it's cut at the exact right length, is completely negligible. Humans have been cutting and setting rubies for millenia, and there are exactly _zero_ that started just emitting a laser beam by trial and error. It took someone calculating what happens there, before you could even know that a laser is possible, and how to make one.
In fact, pretty much the last major invention (that I know of) that was perfected by trial and error, was the light bulb. And, at least according to Tesla, that was a monumentally wasteful undertaking. To quote Tesla, "His method was inefficient in the extreme, for an immense ground had to be covered to get anything at all unless blind chance intervened and, at first, I was almost a sorry witness of his doings, knowing that just a little theory and calculation would have saved him 90 percent of the labor. But he had a veritable contempt for book learning and mathematical knowledge, trusting himself entirely to his inventor's instinct and practical American sense."
But even that stopped working for anything more complex than a light bulb. There's no way you could design a CPU nowadays by trial and error, for example. Even with specialized tools and massively simulating everything ahead, just one glitch sunk 3DFX. (Their Voodoo 5 was supposed to compete with the Geforce 1, but due to having to fix the malfunctioning chip design produced by their tools, it ended up competing with the Geforce 2 instead.) Now picture doing that layout by dumb trial and error instead. I wouldn't even try.
Heck, even in the job of counting bytes, sometimes the "American approach" (*) you describe would give the awfully wrong results until you've fully ported it. E.g., if the code was written with hard-coded constants for the saved data (which probably wouldn't be the case in Oracle's code, but I've seen it happen in other places), then compiling and running it would give the wrong results anyway. E.g., if someone saved an int by writing exactly 4 bytes to disk, it would still be 4 bytes for 64 bit code... and the very incorrect answer.
(*) As a side note, I hate thinking of those as "American approach" and "German approach", as it's really just the approach of whatever person gave that answer. I know there are plenty of Americans too who will stop and calculate, because otherwise the
A polar bear is a cartesian bear after a coordinate transform.
Example: TSS-1R. Space Shuttle Columbia deployed this as part of NASA's series of experiments with orbital tethers (for "hanging" craft from other craft and for raising and lowering orbits).
That was a nice tid bit of information, thank-you. Looking it up out of curiosity, it also appears that the TSS-1R experiment on STS-75 was the first time Linux was used in orbit! (http://en.wikipedia.org/wiki/STS-75#Trivia)
Actually, your strategy is exactly what they are doing with 1 major exception. They are looking at using COTs providers rather than EELV to provide the launches. EELV is already supported by DOD and are quite expensive compared to what the others are showing. A falcon 9 costing 30 million delivers the same as atlas V 401 costing 90M.
As to the costs of replacing it, well, I suspect that it will be replaced part by part. In particular, I suspect that Bigelow will be attaching his first section to it. He needs a place to test it and it will probably be attached for free. From there, I think that other nations will simply buy 1 and attach it there as well (for at least the first few put up). In fact, I am guessing that Canada, India, and perhaps Brazil will buy 1 or more and attach to the station. The reason is that they can learn from both NASA and RSA, while they develop their space programs. Once the program is developed enough to do their own launches, then they may choose to break apart.
I prefer the "u" in honour as it seems to be missing these days.
If only that were true, as it is we are learning at such a slow pace and small scale that all the engineers that "learn" from this effort will be retired by the time we try again, much like what is happening now relearning so much stuff from the Apollo program.
Ike
Magnetic bearings have their place but it is not in this sort of application. They excel where the physical contact of normal bearings would cause low lifetime at high speed but in other applications normal bearing are just so much easier to build, use, and replace that their limited lifetimes are not significant.
The space station failure is probably either related to a temperature coefficient mismatch between two parts that are now rubbing or physical damage. A magnetic bearing would not specifically solve either problem.
But you can read as many good books about golf as you want, or ask the best golf players in the world about everything and the rest, you won't become a good golf player unless at some time you try it for yourself. The same of course it true for instruments.
The Tao of math: The numbers you can count are not the real numbers.
What? Another space station up on cinder blocks in the front yard?
But seriously, TFA says that the joint is 10 feet in diameter. And those panels look pretty big to be just left floating around while they strip the gearbox down and put in new bearings or whatever. Wouldn't they be better off bringing a new panel/joint combo up on the next flight, folding the old one up and swapping the woule assembly?
Have gnu, will travel.
New rules. Please shave your legs before take off, not in space!
Engineering is the art of compromise.
I forgot about COTS. If that works, that might chop a good bit off the maintenance costs for the station and drive down the cost of getting experiments to the station (which apparently is big enough an obstacle that the ISS can't fill it's experiment slots even by offering free rent).
Oops, I intended to reply to Windbourne, not to khallow. Sorry, khallow.
I thought of this when I read about the joint damage. As far as I know they never found the source of the crunching noise.
It could also be something as mundane as a bad heat treat in a bearing leading to launch-load brinelling and subsequent low cycle fatigue. Or maybe they got the launch loads wrong because something resonated and that caused the damage. Or something could have been assembled too tightly.
What I'm curious about is how the metal chips got on the outside of the thing, I would have thought there would be a casing around the mechanism.Equine Mammals Are Considerably Smaller
Why didn't they use some Dura-Lube? With all the infomercials they had a few years ago, you would have thought it could lubricate ANYTHING.
Just vacuum out the joint.
Oh. Never mind.
All these stupid problems could be avoided by following the known universal patterns that never fail. These ships are supposed to be designed ROUND, in the shape of a small Moon.
Currently #2: http://end-times-hoaxes.blogspot.com/ from http://www.google.com/search?hl=en&q=%22hoaxes+exposed%22 Google, God's angelic warrior in Illuminati End Times - Information Highway Parallel Lanes - Traffic Jam in the Lane to Hell... http://end-times-information.blogspot.com/