A Space elevator is extending from a ship-borne anchor to a counterweight in orbit. The ribbon is kept taut due to the rotation of the earth (and that of the counterweight around the earth). At its bottom, it pulls up on the anchor with a force of about 20 tons. Electric vehicles, called climbers, ascend the ribbon using electricity generated by solar panels and a ground based booster light beam. The ribbon is 62,000 miles long, about 3 feet wide, and is thinner than a sheet of paper. (Click to enlarge)
Ben engineering the tether anchor on the gantry on October 19. Image by Bob Winmill. (Click to enlarge)
The test ribbon is up! It's a long way up there, and this is just the bunny slope! Image from October 21, by Marc Schwager. (Click to enlarge)
Saturday a number of the teams did some serious re-engineering of their climbers. This Space elevator was put up for sale on Ebay for US $2,500.00. (Click to enlarge)
Snow Star I is first to climb a tether using directed energy as the power source on October 23. Image by Robert Winmill. All images courtesy of Spaceward.org (Click to enlarge)
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Space elevator reaches 40 feet, contest to continue next year
Posted: Oct 24, 2005 10:36 pm EDT
A space elevator competition was held on October 22 and 23 at the NASA Ames Research Center. Unfortunately, nobody won.
"It actually started at 4pm Friday when the company (that will remain nameless) that was to supply our generator called and said that he didn't have the 70,000 watt generator we needed to run our searchlight over at NASA! Have you ever tried to find a 70 kilowatt generator on a Friday afternoon??!!" begins the organizer, Spaceward Foundation's debrief.
"BTW, note that you can't tow a 70,000 watt generator with a Subaru wagon. Ask us how we know."
Solar cell vehicle climbed 40 ft up a blue ribbon
The event was split into two competitions worth $50,000 each to test either robot climbing or tether strength. The robots, an assemblage of solar cells, metal braces and off-the-shelf rollers were to scale as far as possible up a 200 ft blue tether at a speed of 3 ft per second using photoelectric cells to convert radiation from a NASA 10,000-watt industrial searchlight into electricity for the climb.
"We loaded 4 climbers on the gantry with mixed results. Universally they are struggling with the power budget and the power/weight ratios involved in the contest. UBC Snowstar was the star of the show as they were able to launch of the lift pad and climb up the bottom portion of the ribbon (Ed note: 40 ft)."
Saturday a number of the teams did some serious re-engineering of their climbers. One Space elevator was put up for sale on Ebay for US $2,500.00.
NASA won
The tether loop was another problem, it could only weigh 2 grams and must prove 50% stronger than the house 3 gram Zylon tether provided by NASA.
Centarus Aerospace managed to carry 1200 pounds on their Spectra tether before snapping, "The house tether won the contest. How close was this? We hooked up a (large) chain and kept going with the house tether. The house tether broke at a little over 1300 pounds. Flint was within about 10% of winning the purse! "
Next year, the top prizes will rise to $100,000. The hopes rests on other power sources such as lasers and microwaves, and future lightweight materials such as carbon nanotubes.
Arthur C. Clarke was once asked when mankind would build the first space elevator. His answer was 50 years after people stop laughing. He has since downgraded his estimate to ten years.
A Space elevator tether is extending from a ship-borne anchor to a counterweight well beyond geo-synchronous orbit. The ribbon is kept taut due to the rotation of the earth (and that of the counterweight around the earth). At its bottom, it pulls up on the anchor with a force of about 20 tons.
Electric vehicles, called climbers, ascend the ribbon using electricity generated by solar panels and a ground based booster light beam. In addition to lifting payloads from earth to orbit, the elevator can also release them directly into lunar-injection or earth-escape trajectories. The baseline system weighs about 1500 tons (including counterweight) and can carry up to 15 ton payloads, easily one per day.
The ribbon is 62,000 miles long, about 3 feet wide, and is thinner than a sheet of paper. It is made out of a carbon nanotube composite material, 300 times stronger than steel. The climbers travel at a steady 200 kilometers per hour (120 MPH), do not undergo accelerations and vibrations, can carry large and fragile payloads, and have no propellant stored onboard.
Orbital debris are avoided by moving the anchor ship, and the ribbon itself is made resilient to local space debris damage.
The elevator can increase its own payload capacity by adding ribbon layers to itself.
The Spaceward Foundation
The Spaceward Foundation is a public-funds 501(c)(3) educational non-profit dedicated to the advancement of space science and technology in educational curriculums.
The first program, Elevator: 2010, is a public challenge centered around the Space Elevator concept, offering a substantial prize for the first laser-powered tether climbing demonstration that can meet specific criteria.
The challenge is intended to be difficult (hence the 2010 deadline) and physically impressive - using a several miles high balloon-suspended tether, and a beamed-power system larger than has been built to date.
The foundation's most visible exhibit, the Space Elevator demonstrator, features a working Space Elevator ascending and descending a 200 foot (20 story) tall vertical ribbon, powered from below by a brilliant beam of light:
"The image of a Space Elevator climber, caught in a beam of light and ascending an almost invisible ribbon is such a new paradigm. During the daylight hours, it's impressive. Against a darkened sky, it's a sight to behold," writes the foundation website.
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