Tensions Rise At Space Elevator Challenge

New Scientist ^ | 10-22-2006 | Kelly Young

[blam]

Tensions rise at space elevator challenge

21:40 22 October 2006
NewScientist.com news service
Kelly Young, Las Cruces

An emotionally charged, late-night competition to test the strength of tethers designed for use in space elevators ended with no one walking home with the $200,000 first prize on Saturday.

Designs for future space elevators call for robotic platforms to carry payloads into space on 100,000-kilometre-long tethers. Proponents of the idea say the method would be cheaper than launching rockets, but the requisite technology still needs to be developed.

So in 2005, NASA began sponsoring the Tether Challenge to spur breakthroughs in building cables for the elevators.

"The single most important thing about building a space elevator is that the tether is very strong and very light," says Ben Shelef, founder of the Spaceward Foundation, which administers the competition for NASA.

In the competition, teams must use tethers that weigh no more than 2 grams and must be able to carry more weight before breaking than a NASA-built "house" tether that weighs 3 grams. Each tether is made of a single fibre wound into a loop many times. A special machine then stretches the loop to the breaking point.

The challenge, held at the Wirefly X Prize Cup in Las Cruces, New Mexico, US, did not get started until 2300 MDT on Saturday (0500 GMT on Sunday).

It was immediately beset by controversy. Four teams were supposed to compete head-to-head in the challenge. But three teams – called Centaurus, Fireball and Snowstar – were all disqualified for winding their fibres into too narrow of a loop.

Disqualified teams

According to the rules, the circumference of the loop must measure at least 2 metres. Some came quite close – the Snowstar team from Canada's University of British Columbia. . .

[blam]

Ping.

[kinoxi]

They should increase the prize money a little bit promote more serious competition. Three fourths of the entries were measured wrong?

[RightWhale]

Meanwhile, another space elevator challenge that involves robot climbers racing each other to the top of a long ribbon also became mired in controversy on Saturday (see the New Scientist Space blog Space elevator scandal).

According to the rules, the robots were supposed to climb a ribbon at least 50 metres long at a rate of 1 metre per second or faster. But organisers realised they did not know whether the ribbon used in the competition was 50 metres or 60 metres long.

The length is crucial, since a team from Canada's University of Saskatchewan ascended the ribbon in 58 seconds – fast enough to qualify for the $150,000 top prize if the ribbon is 60 metres but not if it is 50 metres.

Other teams, however, say the University of Saskatchewan should not qualify for the prize regardless of the length of the ribbon because their robot got stuck at the top and was not able to descend the ribbon again in a controlled fashion, as the rules state.

[Balding_Eagle]

because their robot got stuck at the top and was not able to descend the ribbon again in a controlled fashion, as the rules state.

That's interesting. While not quite what happened in the real story (real story?) it is close enough to catch my attention.

[Westlander]

I have the magic lube for the tether...ha ha ha..

[biff]

spider web silk. just need a hell of a lot of spiders.

[Fatuncle]

You know, in all seriousness, I have never seen any group or individual address a major problem of the space elevator concept - orbital debris. I cannot understand how any strand stretching from the ground to a point way the hell out beyond geosync, all other problems being solved, can survive a collision with a chunk of trash moving at orbital velocities.

And how the dickens are you going to deal with an increasingly crowded sky, when every satellite in it orbits at or below geosync? In A C Clarke's story, the sky is swept. How are we to do that?

Or is it a case of solve the problems you can now, and hope the solutions for the ones you can't will come along later?

[Louis Foxwell]

Or is it a case of solve the problems you can now, and hope the solutions for the ones you can't will come along later?

Well, DUH!
How is it possible to solve problems that are unforeseen or do not yet exist?

[Reaganesque]

Well, the DARPA robotic vehicle challenge didn't go so well it's first year out either. Most of the vehicles failed to go much beyond the starting line. The next year, however, five finished the course in impressive fashion. I imagine next year's X-Prize Cup will be far more successful than this year's.

[Fatuncle]

This problem is foreseen, and exists now - the shuttle has come home more than once with a hole or ding from orbiting debris. And most of that is accumulated from stuff moving in more or less the same orbit, at much the same speeds.

The elevator "cable" would be stationary, and anything hitting it would be at orbital velocities or greater.

[mikrofon]

Tensions rise at space elevator challenge

You'd expect the materials used to be under tension.

Anyway, they'll eventually select one option or t'ether...