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Climbing elevator. A climbing elevator is a self-ascending elevator with its own propulsion. The propulsion can be done by an electric or a combustion engine. Climbing elevators are used in guyed masts or towers, in order to make easy access to parts of these constructions, such as flight safety lamps for maintenance.
The Bailong Elevator ( Chinese: 百龙电梯; literally Hundred Dragons Elevator) is a glass double-deck elevator built onto the side of a cliff in the Wulingyuan area of Zhangjiajie, People's Republic of China, an area noted for more than 3,000 quartzite sandstone pillars and peaks across most of the site, many over 200 metres (660 ft) in height.
- History
- In Fiction
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- International Space Elevator Consortium
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Early concepts
The key concept of the space elevator appeared in 1895 when Russian scientist Konstantin Tsiolkovsky was inspired by the Eiffel Tower in Paris. He considered a similar tower that reached all the way into space and was built from the ground up to the altitude of 35,786 kilometers (22,236 miles), the height of geostationary orbit. He noted that the top of such a tower would be circling Earth as in a geostationary orbit. Objects would acquire horizontal velocity due to the Earth's rotation as th...
20th century
Building a compression structure from the ground up proved an unrealistic task as there was no material in existence with enough compressive strength to support its own weight under such conditions. In 1959, the Russian engineer Yuri N. Artsutanov suggested a more feasible proposal. Artsutanov suggested using a geostationary satellite as the base from which to deploy the structure downward. By using a counterweight, a cable would be lowered from geostationary orbit to the surface of Earth, wh...
21st century
To speed space elevator development, proponents have organized several competitions, similar to the Ansari X Prize, for relevant technologies. Among them are Elevator:2010, which organized annual competitions for climbers, ribbons and power-beaming systems from 2005 to 2009, the Robogames Space Elevator Ribbon Climbing competition, as well as NASA's Centennial Challenges program, which, in March 2005, announced a partnership with the Spaceward Foundation (the operator of Elevator:2010), raisi...
In 1979, space elevators were introduced to a broader audience with the simultaneous publication of Arthur C. Clarke's novel, The Fountains of Paradise, in which engineers construct a space elevator on top of a mountain peak in the fictional island country of "Taprobane" (loosely based on Sri Lanka, albeit moved south to the Equator), and Charles S...
Apparent gravitational field
An Earth space elevator cable rotates along with the rotation of the Earth. Therefore, the cable, and objects attached to it, would experience upward centrifugal force in the direction opposing the downward gravitational force. The higher up the cable the object is located, the less the gravitational pull of the Earth, and the stronger the upward centrifugal force due to the rotation, so that more centrifugal force opposes less gravity. The centrifugal force and the gravity are balanced at ge...
Cable section
Historically, the main technical problem has been considered the ability of the cable to hold up, with tension, the weight of itself below any given point. The greatest tension on a space elevator cable is at the point of geostationary orbit, 35,786 km (22,236 mi) above the Earth's equator. This means that the cable material, combined with its design, must be strong enough to hold up its own weight from the surface up to 35,786 km (22,236 mi). A cable which is thicker in cross section area at...
Cable materials
Using the above formula we can calculate the ratio between the cross-section at geostationary orbit and the cross-section at Earth's surface, known as taper ratio:[note 1] The taper ratio becomes very large unless the specific strength of the material used approaches 48 (MPa)/(kg/m3). Low specific strength materials require very large taper ratios which equates to large (or astronomical) total mass of the cable with associated large or impossible costs.
There are a variety of space elevator designs proposed for many planetary bodies. Almost every design includes a base station, a cable, climbers, and a counterweight. For an Earth Space Elevator the Earth's rotation creates upward centrifugal forceon the counterweight. The counterweight is held down by the cable while the cable is held up and taut ...
Launching into deep space
An object attached to a space elevator at a radius of approximately 53,100 km would be at escape velocity when released. Transfer orbits to the L1 and L2 Lagrangian pointscould be attained by release at 50,630 and 51,240 km, respectively, and transfer to lunar orbit from 50,960 km. At the end of Pearson's 144,000 km (89,000 mi) cable, the tangential velocity is 10.93 kilometers per second (6.79 mi/s). That is more than enough to escape Earth's gravitational field and send probes at least as f...
Extraterrestrial elevators
A space elevator could also be constructed on other planets, asteroids and moons. A Martian tether could be much shorter than one on Earth. Mars' surface gravity is 38 percent of Earth's, while it rotates around its axis in about the same time as Earth. Because of this, Martian stationary orbit is much closer to the surface, and hence the elevator could be much shorter. Current materials are already sufficiently strong to construct such an elevator. Building a Martian elevator would be compli...
The construction of a space elevator would need reduction of some technical risk. Some advances in engineering, manufacturing and physical technology are required.Once a first space elevator is built, the second one and all others would have the use of the previous ones to assist in construction, making their costs considerably lower. Such follow-o...
The International Space Elevator Consortium (ISEC) is a US Non-Profit 501(c)(3) Corporation formed to promote the development, construction, and operation of a space elevator as "a revolutionary and efficient way to space for all humanity". It was formed after the Space Elevator Conference in Redmond, Washington in July 2008 and became an affiliate...
The conventional current concept of a "Space Elevator" has evolved from a static compressive structure reaching to the level of GEO, to the modern baseline idea of a static tensile structure anchored to the ground and extending to well above the level of GEO. In the current usage by practitioners (and in this article), a "Space Elevator" means the ...
The Space Elevator: 'Thought Experiment', or Key to the Universe? Archived February 1, 2020, at the Wayback Machine. By Sir Arthur C. Clarke. Address to the XXXth International Astronautical Congre...The Santa Justa Lift ( Portuguese: Elevador de Santa Justa, pronounced [elɨvɐˈðoɾ ðɨ ˈsɐ̃tɐ ˈʒuʃtɐ] ), also called Carmo Lift ( Portuguese: Elevador do Carmo, [elɨvɐˈðoɾ ðu ˈkaɾmu] ), is an elevator, or lift, in the civil parish of Santa Justa, in the historic center of Lisbon, Portugal. Situated at the end of Rua de ...
- Neo-Gothic
- Portuguese Republic
- c. 1899
- Lisbon, Portugal
An elevator pitch, elevator speech, lift speech, or elevator statement is a short description of an idea, product, or company that explains the concept in a way such that any listener can understand it in a short period of time. This description typically explains who the thing is for, what it does, why it is needed, and how it will get done.
Central–Mid-Levels escalator. / 22.28361°N 114.15472°E / 22.28361; 114.15472. The Central–Mid-Levels escalator and walkway system in Hong Kong is the longest outdoor covered escalator system in the world. The system covers over 800 m (2,600 ft) in distance and traverses an elevation of over 135 m (443 ft) from bottom to top.
Electrification. 15 kV, 16.7 Hz AC Overhead lines. System map. The Munich S-Bahn ( German: S-Bahn München) is an electric rail transit system in Munich, Germany. "S-Bahn" is the German abbreviation for Stadtschnellbahn (literally, "urban rapid rail"), and the Munich S-Bahn exhibits characteristics of both rapid transit and commuter rail systems.
