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Fraser
2005-Apr-27, 05:47 PM
SUMMARY: The Liftport Group of space elevator companies has announced that it will be building a carbon nanotubes manufacturing plant in Millville, New Jersey, to supply various glass, plastic and metal companies with these strong materials. Although Liftport hopes to eventually use carbon nanotubes in the construction of a 100,000 km (62,000 mile) space elevator, this move will allow it to make money in the short term and conduct research and development into new production methods.

View full article (http://www.universetoday.com/am/publish/liftport_manufacture_nanotubes.html)

What do you think about this story? Post your comments below.

antoniseb
2005-Apr-27, 06:11 PM
I hope they have rapid success.

John L
2005-Apr-27, 06:32 PM
I follow the Liftport activities and those of a new NASA iniative on the Space Elevator. I think we'll see the first one built before 2025.

Greg
2005-Apr-27, 07:04 PM
Excellent news. The payoff for liftport if they succeed in building the first space elevator would be enormous. So it makes perfect sense for them to get out ahead in the field this early. Their efforts may well catch the attention of other firms, perhaps sparking competition that will move development along even faster.

Fraser
2005-Apr-27, 07:11 PM
I don't normally cover this kind of business news, but I thought this was just too cool.

Don Alexander
2005-Apr-27, 07:19 PM
Wow! First Virgin Galactic, now this.

The future is NOW!!!

Thanks, Fraser.

TuTone
2005-Apr-27, 07:58 PM
What is the space elevator going to connect to at the end of the elevator?

antoniseb
2005-Apr-27, 08:15 PM
Originally posted by TuTone@Apr 27 2005, 07:58 PM
What is the space elevator going to connect to at the end of the elevator?
space.

(and some large thing that we build there at the other end).

piersdad
2005-Apr-27, 08:22 PM
- So you use the space elevator to get up to 100,000 km and then you have to accelerate to 17,000 approx km/h to stay up there
or you are in for a very long drop.
- I think these people are using this way out idea to develop nano tube tech and use it in industry the elevator is just the carrot.
- But they wont admit to that will they

There is no material in the universe that would be strong enough to make a wire that long for a convential elevator.
- So they will have to have some sort of propulsion and at some considerable speed ie 1000 km ph
- So duh!? the elevator will have to have a vaccume in it to be efficient.
so after 100 hours of flight time you then get on board another rocket and get up to orbital speed.

- Before you leave you had better get a pie from the eating place there.

a pie in the sky

TuTone
2005-Apr-27, 09:18 PM
What is the space elevator going to be primarily used for?

John L
2005-Apr-27, 09:26 PM
- So you use the space elevator to get up to 100,000 km and then you have to accelerate to 17,000 approx km/h to stay up there
or you are in for a very long drop.
The gravitational center of the elevator is maintained at geosynchronus orbit. The gravitational pull on the cable keeps it firmly attached at the Earth end and centrifugal forces hold the upper end taught in space because a counterweight is attached at the end. Like a ball tied to a string the you swing around your head - the ball stretches the string taught. This keeps the whole assembly traveling at a speed sufficient to maintain the cable over one spot. If you let go below geosynchronus orbit altitude you will end up in Earth orbit. If you let go at geosynchronus orbit you will simply float next to the cable. If you let go at a sufficient height above geosynchronus orbit you will be exceeding Earth's escape velocity and launch out into the solar system.


- I think these people are using this way out idea to develop nano tube tech and use it in industry the elevator is just the carrot.
- But they wont admit to that will they
Carbon Nanotubes don't need a way-out application. Industry already uses them and wants more of them - LOTS MORE. Like the article said they are already being used to reinforce and strength glasses and plastics.


There is no material in the universe that would be strong enough to make a wire that long for a convential elevator.
- So they will have to have some sort of propulsion and at some considerable speed ie 1000 km ph
- So duh!? the elevator will have to have a vaccume in it to be efficient.
so after 100 hours of flight time you then get on board another rocket and get up to orbital speed.
When the idea was first proposed they joked that the material needed to make the cable was unobtainium because the strongest known materials could not withstand the tension calculated by the engineers. Then Carbon Nanotubes were discovered and they far exceed the tensile strength needed, but are too small in the form currently producable. The goal of this project is to generate cash flow from producing existing nanotubes and fund research into long nanotube production. It is estimated that the nanotubes will need to be uniform in strength and about 1mm long to be usable in the produciton of the elevator. Now the longest ever produced that I've read about were over 3cm long, but were of poor quality and consistency. We're close, though.

And it won't be a conventional elevator. It will in fact be a meter wide, milimeter thick epoxy-nanotube composite ribbon stretching from a floating platform at the equator to out past geosynchronus orbit. There will not be an elevator shaft. Climbers will use rollers on opposite sides of the ribbon to drive up the ribbon at speeds of about 200 km/h. Yes, it will take a while to even reach geosync orbit altitude, but at about 1/10th to 1/100th the cost of a modern rocket per lift it will be worth the travel time. And the masses that can be lifted using this system far exceed even the Ariane 5 and the Space Shuttle.

John L
2005-Apr-27, 09:33 PM
Originally posted by TuTone@Apr 27 2005, 03:18 PM
What is the space elevator going to be primarily used for?
Right now it cost anywhere from $3,000,000 to $400,000,000 to launch on rockets from the simplest conventional rockets to the Space Shuttle. On the Shuttle it costs $10,000 per pound to launch something into space, and it only flies a few times a year. The goal of the space elevator is to get the cost per pound below $500 and to be able to lift tons of payload each day. Instead of taking a decade to build the tiny International Space Station you could assemble one that would make Arthur C Clark proud in a few years.

Also, riding the cable to its 100,000 km length and letting go will leave you traveling at greater than the Earth's escape velocity. Instead of needing to haul tons of fuel to take years to travel across the solar system you could time your release to launch you toward most destinations in the solar system and save all your fuel until you arrive. Even better, build a space elevator here on Earth, send another in compact form up the first one and sling shot it to Mars. Then you can lauch a payload from Earth straight to Mars, have it capture the Mars elevator and ride it down to the surface. Instead of a few cramped little pods for a 6 person expedition to Mars we could send 100 pods and build a city on the surface where thousands of scientists could work. The same system could work to send massive payloads and large groups of people to any destination in the solar system.

400poundgorilla
2005-Apr-27, 11:27 PM
Wow. This whole concept sounds too good to be true if you asked me. Not that I want to be negative about it though... It just seems like there are going to be a lot of variables. If we actually pull it off, it would be the greatest engineering feat of all time. (until the next one that's better of course) In the class of the wonders of the world, etc. Developing an ultra-high tensile material is only ONE of the challenges! A climber might be easy by comparison. Anchoring this thing to the earth... how? what about weather? wind resistance? Space debris?

John L, you seem to be more in the know about this project... any more juicy details... size/weight of the centrifugal counterweight? effects of the climber in motion? ...under weather? What studies have actually been done and where can we find these? I know NASA is holding X-prize like contests for tethers and climbers towards this end as well...

I would LOVE to see this work in my lifetime! But will it? Will it work at all? It seems that we may be a little over confident.

TuTone
2005-Apr-27, 11:55 PM
Yeah, I feel the same gorilla. I hope its not money wasted.

piersdad
2005-Apr-28, 12:43 AM
thanks for the clarification john l
the mind boggles at the problems of actually getting it up there
from the ground up the top will have to be accelerated to get into geo synchronous orbit and if launched into space it will have to be accelerated again to reach the earths rate of spin.

hop on a childs round about and move rapidly inwards and you will see what i mean your body has to slow down to the slower pace of the centre part and visa versa

sam_lelime
2005-Apr-28, 02:53 AM
The speed of the Pendulum is slower at the top and higher at the bottom... reverse the effect and deducte the reverse effect and you roughly have the concept. And as you get closer to the platform you will become part of the biggest mass, you are closest to the portion of…….
If you guys want the formula I can look up my physics book and fetch it
A space elevator will work… not sure of the measurements and so on.

However is it possible to build one.. Well that requires a lot more research. I don’t have enough information to say:
But in effort to stay positive, I’ll do my own research into the idea. …
That is me as scientist… as Business man however after the construction of TP101
I think Carbon nanotube are worth investing into regardless of the space elevator idea.

piersdad
2005-Apr-28, 04:07 AM
Hmm lets say we are about to take a 1 ton weight to the top of the elevator.
- Now the elevator would be essentially flexible and as the weight rises it has to be continuously accelerated to the new orbital speed so as the weight rises it will strech the elevator like a bow string and so the top of the elevator will have to resist this force by pullng upward and forward or it will be pulled out of geo stationary orbit.
L O L to do this they will have to use the same amount of rocket power as a rocket launched into orbit from a high flying aeroplane into space.

As much as it is a great idea any weight going up the elevator is going to swing the elevator out of orbit even if it is in a higher than geostationary orbit it will still get pulled down by any weight being accelerated to the speed of geo stationary orbit.
un less the weight is rocket powered so whats the advantage


wait on geo stationary orbit is about 400 miles what is the other 96.000 miles for ?
even with the inertia of elevator that height i think that as there is no free energy the top will have to be pulled down by the weight of the rising payload unless the payload is self powered.

John L
2005-Apr-28, 02:41 PM
Here a few sites where I learned all I know about the Space Elevator concept. Several contain FAQs that answer the questions you are all posing. You should understand that there has been about 50 years of research into this idea and I feel confident that the issues have been adressed.

This site (http://www.isr.us/SEHome.asp) is where I first learned the details of the space elevator. This was a NASA funded study into the feasibility and major issues facing the concept. They first looked at requiring a tower at the base of up to 16km in height, but it has been determined that such a tower is not necessary.

Liftport (http://www.liftport.com/index.php) is the company founded by some of the guys that did that NASA study. They have already invested research dollars into the lifter technology and the power systems, and are now working directly on the cable issue.

This site (http://www.elevator2010.org/site/index.html) is a new NASA funded X-Prize type project to encourage the development of the technologies needed for the cable and lifters.

Basically, the anchor on the Earth end will be a floating platform stationed in the Eastern Pacific ocean at the equator - an area with very little weater activity. By using a floating platform similar to the Sea Launch system the entire space elevator will be movable to avoid tracked space debris and satellites. The obstacles still facing the project are mass production of carbon nanotubes of a uniform length and strength, testing that the cable will not be excessively degraded by upper atmosphere oxygen, and proving the beamed power concept in practice.

Nick4
2005-Apr-28, 03:26 PM
It sounds hard to belive that we are making things like this. But it will be alot beter and faster to get into space.

John L
2005-Apr-28, 03:48 PM
Originally posted by Nick4@Apr 28 2005, 09:26 AM
It sounds hard to belive that we are making things like this. But it will be alot beter and faster to get into space.
Better and Faster depends on what you mean. It will take about two weeks to make the trip from the anchor station to geosynchronus orbit, but they'll be able to run payloads up and down all day everyday, so in the long run we'll be able to get more up into space faster than using the occasional launch of rockets. And since rockets will not be used anymore we'll stop dumping chemicals into the atmosphere from burned fuel and we'll stop leaving large sections of rockets in orbit that will help us clean up near Earth orbit.

John L
2005-Apr-28, 06:56 PM
Today at Space.com (http://www.space.com/astronotes/astronotes.html) is an Astronotes story both on Liftport's new plant and further discussion of the space elevator.


A space elevator may be the only way to cut down costs for access to space. That’s the view of Wolfgang Demisch, owner of Demisch Associates LLC, an aerospace financial consultancy.

Demisch told Congress last week that access to space will stay expensive “until we can achieve something like the proposed space elevator,” with need to mobilize the talents of people “to realize the materials and power technologies that underpin such a transformative capability,” he said.

400poundgorilla
2005-Apr-28, 08:37 PM
John,

I was reading the informative link that you referred us to. It looks like it has been quite well thought out but needs brave pioneers to champion the cause. ...and likely a bold president that could divert 10% of our war budget to fund this most exciting challenge.

A quote from the site:

This manuscript is not intended to be the final word on any aspect of the space elevator. It is intended to be a starting point. The next stage is not to form large design committees but to get armies of graduate students and researchers examining each individual aspect of the scenario we have presented. Carbon nanotube composites, meteor impacts, weather, orbital mechanics of the deployment, induced oscillations from every source, power beaming, on-orbit operations, electric propulsion, atomic oxygen, nanotube and epoxy coating, climber design, cable spooling and cable design all need to be studied and can be done by many small programs. Once the individual efforts have produced the needed information, a technically-driven, fiscallyresponsible team of committed individuals can be formed to build the space elevator. With a concerted and objective effort we could begin construction of the space elevator in the coming decade.
SO WHAT ARE YOU GRADUATE STUDENTS WAITING FOR? This looks like exciting real world work here.

John L
2005-Apr-28, 08:52 PM
400 Pound Gorilla,

The 3rd link I posted for the Elevator 2010 (http://www.elevator2010.org/site/index.html) project is a NASA funded (that means the President approved adding these prizes into NASA's budget) X-Prize like competition to get university teams and corporations to attack the biggest design issues like cable material and climber power, lifting capacity, and speed. The project seems to be geared to working out all of the issues over the next 5 years so that all of the materials needed to build the first space elevator are available.

vet
2005-Apr-28, 11:27 PM
my cousin's husband was w/NASA before being 'outsourced' to 'martin-marietta'---his job ranged from controlling most, even 'shuttle-burns' and doing the orbitals of all the 'space-junk' of concern. there's much more up there than the public realises.
my last visit to houston, he showed me a glimpse of what he was up-against---amazing.

how may this elevator defend itself from such? it's one thing to order a sattelite, or shuttle burn---they are not fixed objects. my other wonder is why a structure of 67,000 kliks?

piersdad
2005-Apr-29, 04:21 AM
The ribbon is 62,000 miles long, about 3 feet wide, and is thinner than a sheet of paper. It is made out a material called Carbon Nanotube Composite
ok it seems that at 62,000 miles the cenrtipal force is as they quote 20 tons pull on the ribbon.
so they can lift up to 15 tonns at a time using electrically powered lifts climbing up the ribbon.

i can imagine they will have a way station at geo synchronus orbit where the load is released and it has to then use its own power to change its orbit otherwise the ribbon will be permanently deflected.
I cant imagine at the moment where the energy is going to come from to accelerate the rising load to geosyn, orbital speed as the side ways acceleration will deflect the ribbon.

Vaguely i imagine the effort to accelerate the load will react against the earths spin and slow the earths rotation a un-imaginable small amount.

So the base station on the ground will be pushed sideways as the load rises and as this reaction is from outside the earth it will slow the earth down.

so yes i am thinking that it is feasable and a ribbon taken in bulk into geo stationary orbit could be rocketed both down and up wards at the same time eventually reaching both earth and near the 62,000 mile orbit at the same time.

they could possibly be unwinding the ribbon slowly day by day and keeping it ballanced steering it into a verticle downward/upwqard way till it gently gets anchored on earth and then the upper portion further extended to create the 20 tonn pull required to enable loads to lift off.

so im a lot less skeptical now ;)

John L
2005-Apr-30, 12:31 AM
Piersdad,

I was the same as you when I first heard about it, too. How could that possibly work? What could withstand the tension? Wouldn't it just snap, tilt and fall, etc?

But now like you, I've read the studies and seen the research and see that its actually possible. Yes, the cable/ribbon still needs research to make it strong enough and light enough, but we're past the unobtainium and have a real material that can do the job. And you're right that the elevator and its loads will slow the Earth an extremely tiny amount, but the Boxing Day quake that caused the Indian Ocean tsunamis sped it up a bit. Our rotation speed changes a little bit this way and that all the time, and the Moon slows us down a little each year, too. The amount is tiny.

From what I've seen in the studies of the elevator concept, the continuous outward force on the cable will keep it from being deflected out of alignment more than about 1%, and when the load reaches geosync the cable is back at verticle.

And the best idea for powering the lifters is a laser tuned to a frequency that is the highest efficiency for conversion to electricity by solar cells. The studies I've read show that by tuning a laser to the right frequency they can get 85% efficient conversion to electicity by solar cells.

Vet22,

The problem of orbital debris is a serious one. The two things the elevator will have is the ability to move. The anchor station will be a floating platform that can be moved around to ensure that the ribbon is out of the way of any known orbital debris. Furthermore, the ribbon will be designed with criss-crossing bands of material so that if a tiny, untrackable piece of debris hits the cable it will put a hole clean through without severing the entire ribbon. And at one meter across, it will have a large area to absorb the tiny micro-debris hits. They also want to design a lifter that can monitor the ribbon and repair any holes.

piersdad
2005-Apr-30, 01:19 AM
another convert here just the tech details to process.

to simplify the concept i imagined a tennis ball whirling around my head and a slow moving weight was moved along the string to the tennis ball.
the ball will then lag behind a bit till the weight is stationary
and then the vector then created will soon straighten the ball and string to a exact radius again ready for the next weight to be flung out.

Greg
2005-Apr-30, 04:30 PM
I'll post some of my concerns on the topic since this seems to be the dominant theme here. Natural phenomenon are what concerns me the most. What would be the effect of a powerful windstorm such as a hurricane or typhoon? What would be the effect of a lightning strike? Can it withstand upper level winds which can get quite fast? If it is out in the ocean, how do we protect it from terrorists? Since it is in outer space what would happen if a piece of space debris or a meteor were to hit it?

piersdad
2005-Apr-30, 07:05 PM
Natural phenomenon are what concerns me the most. What would be the effect of a powerful windstorm such as a hurricane or typhoon? What would be the effect of a lightning strike? Can it withstand upper level winds which can get quite fast?
your concerns are very valid and the shape and construction of perhaps the lower level of the ribbon will differ from the upper.
all these dangers have to be addressed befor they start.
i would imagine that with 20 ton pull that wind would have little effect on it. lightening would be a very big concern as it is a lovely lightening rod.

the lower part will be mobile and could if sea born shifted a hundred miles to avoid a storm i would imagine as this would be one prudent solution.

so their tasks are immense ahead and i wish i was a young gratuate able to provide valid input and maybe join the scientific greats of the past

they are looking for people who on their final stages of university ie doctorate can do valid research into the many aspects.

it better to have a gang of enthusiastic graduates than a money hungry consultant
who will provide a solution but leave then too short of money to go further

dragonmaster_us@hotmail.com
2005-May-10, 08:19 PM
Try thinking about it this way.

The elevator won't be a shaft. If it's a structure, it will be on the lines of the Eiffel Tower. that way there can be levels that hold the equipment for a rail gun. There will be no constant strain on the structure trying to lift a box on the end of a cable. With carbon nanotubes, the members can be twined as in a hemp rope (though the visible structure would be a more conventional "I" beam shape. This can be built to withstand the momentary thrust of the magnetic accelerators. The coreollis effect will be compensated for by aiming the accelerator field. Nearing the top, there will be less requirement for acceleration to get to the geo-synchronous orbit position. At the top, the terminal velocity will have been totally controlled to cause it to remain, or to continue on to further heights. This has all been worked out by the science-fiction writers over several decades. It just took the development of carbon nano-tubes to make it a possibility, soon becoming a probability. If a thing is proven to be feasable, and there is an economic benefit, it will be tried, and tried again till it is done.

400poundgorilla
2005-May-10, 09:48 PM
I have to voice some additional concerns even after reading about the extensive foresight that has already gone into aleviating them.

Space junk is one of the big concerns, and they are proposing designing the cable to survive many small piercings, tracking debris so the cable can be moved out of harms way, and have thought about repairability as well. But have they gone far enough? Every year earth passes through many cosmic debris fields, remenents of comets and so forth and there is plenty of junk already in orbit. The longevity of the space stations that have withstood these bombardments should be tribute to survivability from these things, but what about the human element? Can it be protected against terrorists too?

Is there such a thing as a "lightning free" zone? Can this cable really be made to survive a lightning strike? ...one side thought too, this would have to be just about the biggest antennae on the planet, do you think they might let a radio station broadcast from it? :D good source of revenue, no? okay, I digress... All sorts of things can be done to make the cable non-conductive... until it gets wet that is. or frosty/icy. Even at the equator, it gets cold at altitude and there is going to be moisture.

Finally, the oxidation issue seems to be another major hurdle. Coatings are proposed over certain sections, but if these coatings are breached, the degradation of the cable could be very rapid. What types of coatings can really be effectively applied and survive the 200Km/Hr lifters? Is there anything in existence today?

dragonmaster_us@hotmail.com
2005-May-10, 10:15 PM
Very good observation about impact possibilities. The structure will need to be built with redundant supporting members. Just because we have junk up there that hasn't been hit by other junk doesn't mean it is safe. Far from it. A stationary structure will be in the path of almost all orbiting junk sooner or later. The only solution is a continuous repair program, and, as I said, redundancy in the structure itself. When I first heard of the proposal several years ago, I thought about the weight, the queerness of it, and the possibility of the construction. I have seen a few proposals since then and it seems to make more sense as time goes on. I don't see how we can build the top of the structure before the bottom fails, but that is an engineering problem, and structural engineers like impossible projects (Golden Gate Bridge, San Diego Strand Bridge, etc.) This would just be another bridge with one end suported by the ground, the other by centrifuge. I'm sure our Great Grandchildren will be as amazed seeing it, as we are, seeing the Golden Gate. It will be attempted because, theoretically, there is no cheaper way to lift into orbit.