A private group has taken one small step toward the prospect of building a futuristic space elevator.
LiftPort Group Inc., of Bremerton, Washington, has successfully tested a robot climber - a novel piece of hardware that reeled itself up and down a lengthy ribbon dangling from a high-altitude balloon.
The test run, conducted earlier this week, is seen as a precursor experiment intended to flight validate equipment and methods to construct a space elevator. This visionary concept would make use of an ultra-strong carbon nanotube composite ribbon stretching some 62,000 miles (100,000 kilometers) from Earth into space.
The space elevator would be anchored to an offshore sea platform near the equator in the Pacific Ocean. At the other end in space, the ribbon would be attached to a small counterweight. Mechanical "lifters" -- robotic elevator cars -- would move up and down the ribbon, carrying such items as satellites, solar power systems, and eventually people into space.
LiftPort's plan is to take the concept from the research laboratory to commercial development.
"We were very pleased with the test," said Michael Laine, President of the LiftPort Group. "It worked really well," he told SPACE.com.
The assessment of flight hardware took place September 20 at an undisclosed location in eastern Washington. Due to the experimental nature of the equipment, actual whereabouts of the test site can't be revealed, primarily due to safety reasons, Laine said.
"If our 23-pound (10.5-kilogram) robot falls from the ribbon...we don't want spectators to be in the way as it makes a couple thousand dollar crater," Laine explained.
This week's testing involved a 12-foot (4-meter) diameter balloon. Safety lines held by team members kept the balloon from floating away. The ribbon dangling from the balloon was made of composite fiberglass, with the robot lifter running up and down the tether.
"This lifter is much smarter than our previous versions. It's our 18th version," he said, with the Mark VII robot named 'Sword over Damocles' or 'sword' for short. The "belt driven" robot is battery-powered, featuring two motors and an expanded cargo area due to increased intelligence built into the device, he said.
Goal in sight
During the day, the highest altitude reached by the balloon/ribbon/robot combination was 1,000 feet (305 meters). "It gives us complete confidence that the mile goal is well within reach," Laine said.
Laine said that the Federal Aviation Administration (FAA) has been very supportive and helpful in orchestrating their test flights.
"We are cleared up to one mile high, off of a tethered helium balloon," Laine said. "Our series of tests are designed to gain in altitude as we go, as we test our communications, range sensors, global positioning system satellite gear, along with temperature and camera systems."
Miles to go
Further experiment dates have not been pinpointed as yet, although the weather in the area will play a key factor.
"We have a fairly open window to do more tests," Laine said. "We've probably got another month or so if we're going to do it here in Washington State."
Other options are being looked at, such as staging LiftPort hardware tests from Denver, Colorado, as well as Northern California, he added.
Laine and his space elevator team know that they have miles to go - literally - before a space elevator can be shown to be workable.
"But the test was a step in the right direction," Laine said. "It shows that our hardware design is valid."
LiftPort has been busy at work on the space elevator idea for over two years.
Furthermore, the company has created LiftPort Nanotech in Millville, New Jersey. That company is delving into mass production of nanotubes, focused on creating super-strong materials, "because, ultimately, that's what leads to a long and strong ribbon in the sky," Laine said.
"We're not a PowerPoint company anymore...we're a hardware company," Laine concluded.
In a related development, the Spaceward Foundation of Mountain View, California has announced the First Annual Space Elevator Competition, to be held October 21 at NASA's Ames Research Center in Silicon Valley.
Two competitions are being held: The "Tether Challenge" and "Beam Power Challenge". These are two of the key technologies required to build a space elevator.
The Tether Challenge will test the strength and weight of carbon nanotube based materials. The Beam Power challenge will feature climbers attempting to scale a 200-foot (61-meter) tether powered by a high intensity light source.
Prize money is furnished by the NASA Centennial Challenges program. Teams from universities and industry around the country have entered into the competitions.
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