In the model concept art, the lift will be able to carry up to 13 tons of cargo into space, propelled by a laser beam.
Image courtesy of ElevatorPort Group
On April 12, 1981, the Space Shuttle Columbia was launched at the Kennedy Space Center in Florida, starting its first space mission and realizing the dream of reusable spacecraft. So far, NASA has launched more than 100 successful missions, but the price has little room to float. Whether it's a space shuttle or a non-reusable Russian spacecraft, the cost of launch is about $10,000 per pound ($22,000 per kilogram).
A new space transport system is being developed that could put travel to Earthsat orbit (GEO) on the agenda and boost the global economy.
The space lift, made of carbon nanotube composite tape, is fixed to a movable platform at sea, which can extend into about 62,000 miles (100,000 kilometers) of space. Mechanical lifts attached to the lift belt will then load into the lift belt, sending cargo and people into space for just $100 to $400 per pound ($220 to $880 per kilogram).
In this article, we'll look at how the concept of a space elevator moves from science fiction to reality.
The weight at the end of the space elevator conveyor belt space lift will keep the carbon nanotube strip tight.
In order to better sort out the understanding of space elevators, it can be compared to a game in which one end of the rope is tied to the pole and the other end is tied to the ball. In this analogy, the rope is a composite belt of carbon nanotubes, the pole is the earth, and the ball is the weight. Now, imagine the ball spinning around the pole all the time, speeding up so much that the rope tightens. This is the overall idea of the space elevator. The counterweight rotates around the earth, keeping the cable straight and allowing the robot lifter to move up and down on the steel belt.
According to the design proposed by LiftPort (Elevator Harbor Group), the height of the space elevator is about 62,000 miles (100,000 kilometers). LiftPort is one of several companies that have a development program for the space elevator or its components. At the X Trophy in Las Cruz, New Mexico, in October 2006, teams from around the world competed for the first prize in a $400,000 space elevator competition.
At the heart of the elevator is a composite tape of carbon nanotubes, which is only a few centimeters wide and almost as thin as a piece of paper. The discovery of carbon nanotubes in 1991 led scientists to believe that they could be used as building materials for space elevators. According to Dr. Bradley Edwards of the Space Foundation, "Materials manufacturing was too challenging before, but now we are approaching a new phase of creating carbon nanotubes, and in manufacturing machines a lifting belt that can extend to outer space with a large number of materials." According to some early plans, the remaining building materials will be used to process them into counterweights.
Carbon nanotubes may be 100 times stronger than steel and are as flexible as plastic. The strength of carbon nanotubes comes from their unique structure, similar to that of a soccer ball. Once scientists are able to make fibers out of carbon nanotubes, it's possible to create lifting belts for space lifts. Previously available materials are too weak or inflexible to form ribbons and can break easily.
Tom Nugent, research director at LiftPort Group, said: "They have a very high modulus of elasticity and very high tensile strength, all of which theoretically suggest that a material could make space elevators relatively easy to build. ”。
Ribbons can be built in two ways:
Long carbon nanotubes — a few meters long or longer — will be woven into a rope-like structure. As of 2005, the longest nanotubes were still only a few centimeters long.
Shorter nanotubes can be placed in the polymer matrix. Current polymers do not bind well to carbon nanotubes, which causes the matrix to be pulled away from the nanotubes when tension is applied.
Once a long band of nanotubes is made, it will be wound into a spool and then emitted into orbit. When the spacecraft carrying the spool reaches a certain altitude, possibly in low Earth orbit, it will begin to uncool, lowering the ascending belt back to Earth. At the same time, the spool valve will continue to move high into the air. When the lifting belt is placed into the Earth's atmosphere, it will be lowered and fixed on a moving platform in the ocean.
This lifting belt will serve as the track of a railway to space. The lifting belt is then lifted into space with a mechanical lifter.
How well the space elevator performs
If built, this lifting belt will represent a modern world wonder and will be the tallest building ever built. In 2005, the world's tallest independent tower belonged to the CN Tower in Toronto, Canada, and is the tallest national tower in Canada, reaching 1815 feet 5 inches (553.34 meters). The space elevator will be 180,720 times taller than the CN Tower!
The 62,000-mile (100,000 km) long space elevator will be well above the space shuttle's average orbital altitude (115-400 mph/185–643 km). In fact, it is nearly a quarter of the distance to the Moon, which orbits the Earth for a total of 237674 miles (382,500 kilometers).
Take a space elevator to the top of the mountain
Climbers at both ends of the lift will roll up the lift belt at a speed of about 200 mph.
While the lifting belt is still a conceptual component, all other components of the space lift can be manufactured using known techniques, including the [UNK] robotic lifter, the [UNK] anchorage [UNK] and the [UNK] power beam system. By the time the lifting belt is completed, the other components will be ready around 2018.
lift
The robot lift will use a lifting belt to guide it into the air. The traction tread rollers on the lift will clamp the composite pipe belt and pull the lift belt over, allowing the lift to pull into the lift belt.
Stand width
The space lift will come from a maritime movable platform in the equatorial Pacific Ocean that will hold the ribbons fixed to Earth.
Counterweight
At the top of the lifting belt, there will be a counterweight that acts as a balance. Early space lift programs included capturing an asteroid and using it as a counterweight. However, LiftPort and the Institute of Science (ISR) have recent plans to include the use of artificial counterweights. In fact, the counterweight may have been assembled from equipment used to make lifting belts, including spacecraft used to launch lifts.
beam
The lift will be powered by a free electronic laser system located at or near the anchor station. According to the ISR, the laser will emit 2.4 megawatts of energy to the photovoltaic cells, which may be made of gallium arsenide (GaAs) connected to the lifter, which is then converted into electrical energy for use by traditional niobium-magnetic DC motors.
After successful operation, the lift will be loaded into the space elevator every day. The size of the lift will vary from the initial 5 tons to 20 tons. The 20-ton lift will be able to carry up to 13 tons of payload and another 900 cubic meters of space. The lift will transport physical objects from satellites to solar panels at a speed of about 118 miles per hour (190 km/h), ultimately transporting humans.
Space elevator repairs
The space elevator belt will be fixed to a maritime movable platform in the equatorial Pacific Ocean. As part of the system that coordinates elevators to avoid track debris, the mobile platform can be repositioned.
At 62,000 miles (100,000 kilometers) of space elevators, they will be vulnerable to risk factors, including weather, space debris and terrorists. As space elevator design initiatives advance, developers are considering these risks and ways to overcome them. In fact, in order to maintain at least one functioning space elevator, the developer plans to build multiple space elevators. Each budget is cheaper than the previous one. The first space elevator will serve as a platform for building more space elevators. In the process, developers can ensure that one space elevator has a problem, and other elevators can continue to lift the payload into space.
Avoid space debris
Space lifts need to be able to avoid orbiting objects, such as satellite debris. The anchoring platform will use [UNK] active avoidance [UNK] to protect space lifts from such objects. Currently, the North American Aerospace Defense Command (NORAD) tracks objects larger than 10 centimeters (3.9 inches). Securing the space lift requires an orbital debris tracking system that can detect objects about 1 centimeter (0.39 inches) in size. The technology is currently being developed for other space projects.
Tom Nugent of LiftPort said: "We plan to fix the lifting belt on a mobile platform in the ocean. ”。“ In fact, you can move the anchor to separate the lifting belt from the satellite. ”
Strategically evade attacks
The isolated location of the space elevator will be the biggest factor in reducing the risk of terrorist attacks. For example, according to LiftPort, the first anchorage will be located in the equatorial Pacific Ocean, at least 404 miles (650 kilometers) from any route or channel. Only a fraction of the space elevators would be exposed to attack range, 9.3 miles (15 kilometers) or less. In addition, space elevators will be a valuable global resource, likely protected by U.S. and other foreign military forces.
Space elevator impact
Spatial model of the solar landscape.
The potential impact of space elevators is being compared to another great transportation achievement, the U.S. Transcontinental Railway. Completed in Utah's Cape in 1869, the railroad line connected the country's east-west coast for the first time, accelerating immigration to the american west. Cross-border travel has decreased from months to days. It also opened up new markets and spawned entirely new industries. By 1893, the United States had five transcontinental rail lines.
The idea of a space elevator has many similarities to a transcontinental railway. The space elevator will create a permanent passage connecting Earth to space that will not close. While it won't make space travel faster, it will make space travel more frequent and will usher in a new era of development for space. Perhaps the biggest factor driving the idea of a space lift is that it will drastically reduce the cost of sending cargo into space. While slower than chemically propelled space shuttles, the lift will cost from $10,000 to $20,000 per pound, equivalent to about $400 per pound.
According to Bradley Edwards, author of Space Elevators, NIAC Phase II Final Report, the cost of building a space elevator is currently estimated at $6 billion, and the legal and regulatory costs are $4 billion. (Edwards is also President and Founder of Low Carbon Design, Dr. Bradley Carl Edwards.) In 1971, the cost budget for the Space Shuttle program was $5.2 billion, but the incurred cost was $19.5 billion. In addition, the cost of flying each space shuttle is $500 million, more than 50 times more than the initial budget.
Space lifts can replace the space shuttle as the primary means of transportation in space and are used for satellite deployment, defense, tourism, and further exploration. For the latter point, the spacecraft will be teleported onto the elevator's conveyor belt and then launched once in space toward its main target. This type of launch consumes less fuel than a traditional flight out of the Earth's atmosphere. Some designers also believe that space elevators can be built on other planets, including Mars.
NASA funded Dr. Edwards' three-year research. In 2005, however, it only provided $28 million to companies working on space elevators. Although the company is still very interested in the project, it prefers to sit back and watch further development.
Note: The offshore mobile platform is a hovering ball platform, which is mainly used for lifting operation. The design was started a decade ago by fundraising from LiftPort in Tacoma, Washington.
BY: KEVIN BONSOR
FY:jane
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