Posted on 02/15/2006 10:24:11 AM PST by Neville72
In January, LiftPort team members deployed a mile-long tether with the help of three large balloons in the Arizona desert (N Aung/LiftPort Group)Related Articles A slim cable for a space elevator has been built stretching a mile into the sky, enabling robots to scrabble some way up and down the line.
LiftPort Group, a private US company on a quest to build a space elevator by April 2018, stretched the strong carbon ribbon 1 mile (1.6 km) into the sky from the Arizona desert outside Phoenix in January tests, it announced on Monday.
The company's lofty objective will sound familiar to followers of NASA's Centennial Challenges programme. The desired outcome is a 62,000-mile (99,779 km) tether that robotic lifters – powered by laser beams from Earth – can climb, ferrying cargo, satellites and eventually people into space.
The recent test followed a September 2005 demonstration in which LiftPort's robots climbed 300 metres of ribbon tethered to the Earth and pulled taut by a large balloon. This time around, the company tested an improved cable pulled aloft by three balloons.
Rock solid To make the cable, researchers sandwiched three carbon-fibre composite strings between four sheets of fibreglass tape, creating a mile-long cable about 5 centimetres wide and no thicker than about six sheets of paper.
"For this one, the real critical test was making a string strong enough," says Michael Laine, president of LiftPort. "We made a cable that was stationed by the balloons at a mile high for 6 hours…it was rock solid."
A platform linking the balloons and the tether was successfully launched and held in place during the test. LiftPort calls the platform HALE, High Altitude Long Endurance, and plans to market it for aerial observation and communication purposes.
But the test was not completely without problems.
The company's battery-operated robotic lifters were designed to climb up and down the entire length of the ribbon but only made it about 460 m above ground. Laine told New Scientist that the robots had worked properly during preparatory tests and his team is still analysing the problem.
Carbon nanotubes In March, LiftPort hopes to set up a HALE system in Utah's Mars Desert Research Station and maintain it for three weeks. Then, later in the spring, Laine says he wants to test a 2-mile (3.2-km) tether with robots scaling to at least half way up.
Laine aims to produce a functioning space elevator by 2018 – a date his company chose in 2003 based on a NASA Institute for Advanced Concepts study, which said an elevator could be built in 15 years. "This is a baby step, but it's part of the process," he says of LiftPort's recent test.
The idea is to build the actual elevator's ribbon from ultra-strong carbon nanotube composites and to have solar-powered lifters carry 100 tonnes of cargo into space once a week, 50 times a year.
Beams and climbers Laine sits on the board of the California-based Spaceward Foundation, which partnered with NASA to put on two space-elevator-related competitions that were the first of the agency's Centennial Challenges programme – the Tether Challenge and the Beam Power Challenge.
The first is designed to test the strength of lightweight tethers while the beam challenge tests the climbing ability and weight-bearing capability of robots scaling a cable. Laine’s team is not competing in the NASA challenges so there is no conflict of interest.
In October 2005, none of the competition entrants performed well enough to claim the twin $50,000 purses. But the challenges are scheduled to take place again in August 2006 with $150,000 top prizes. Nineteen teams have signed up for the beam power challenge so far and three will compete in the tether challenge.
Ben Shelef, founder of the Spaceward Foundation, hopes the competitions will drum up interest and drive technological innovation. He told New Scientist he is pleased to hear of LiftPort's successful test. "A journey of a thousand miles starts with a single step," he says.
And we all are equally excited for the glorious day when this monument to human achievement will be blown to bits for the glory of Allah, killing as many jews and infidels as possible.
Awesome indeed!
The guy who comes up with that kind of a control system will win fame and fortune for sure!
In some places, yes. In others, it's slower. Folks 'round here call that "weather".
That's what the little guy said. Not sure I believe him...
Where are people getting the 62,000 miles? Orbit can be reached at only 100 miles altitude. Geo-stationary is only 24,000 miles.
they discovered the material you're talking about last year. Its a kind of carbon nanotube
I agree that terrorism is no reason to not try... but it's defensibility isn't as easy as you might think. You wouldn't even need a small LearJet to cause separation, and you'd have at least the bottom 3 miles to "defend".
I wondered about this myself when I first heard of the project. How is torque dealt with in the plans?
Yeah... I got around to doing that right after I posted that moronic post... Mea culpa.
Then I would take the first express elevator, (sans muzak, LOL) and using the mass of a gazillion billion stars start walking the cat...
...and of course cool the earth with the breeze...
...and also, of course I would have patented a super anti-nausea compound for earth peoples...
...solving both global warming and hiccups.
The idea is that the cable would actually be in orbit, with it's center of mass at the geosync point. Although it would be anchored to provide som additional stability and weather resistance, in theory the cable could be unanchored to the ground and simply have the bottom 'floating' a meter or two off the ground.
As for counterweights/pawer generation, since you already have 50% of the system mass outside geosync (where centripetal accelleration is greater than gravity) weights or payloads moving away from earth could help balance those being lifted from the surface. Also, assuming a decent energy storage system, cars traveling down the cable could power those moving up.
Overall, a promising idea, but will probably require some pretty serious advances in automated production of long-chain nanotubes, or some other yet-to-be-named wonder material.
Paging Mr Gates...paging Mr William Gates....
Scared of progress???
Dangle
A man out walking in the middle of nowhere on a cold day discovers a mysterious cord dangling from the sky. Should he tug on it? Of course!
http://www.atomfilms.com/af/content/dangle
Where do you think the story about Jack and the Beanstalk came from?
It's already there. You have it, everything on earth has it. The earths rotation provides it.
When you jump in the air, does the ground suddenly zoom by at 1037 MPH?
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