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Hovertrain
A hovertrain is a type of high-speed train that replaces conventional steel wheels with hovercraft lift pads, and the conventional railway bed with a paved road-like surface, known as the ''track'' or ''guideway''. The concept aims to eliminate rolling resistance and allow very high performance, while also simplifying the infrastructure needed to lay new lines. Hovertrain is a generic term, and the vehicles are more commonly referred to by their project names where they were developed. In the UK they are known as tracked hovercraft, in the US they are tracked air-cushion vehicles. The first hovertrain was developed by Jean Bertin (1917-1975) in France, where they were marketed as the Aérotrain before being abandoned by the French government. Hovertrains were seen as a relatively low-risk and low-cost way to develop high-speed inter-city train service, in an era when conventional rail seemed stuck to speeds around or less. By the late 1960s, major development efforts were underw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aérotrain
The Aérotrain was an experimental Tracked Air Cushion Vehicle (TACV), or hovertrain, developed in France from 1965 to 1977 under the engineering leadership of Jean Bertin (1917–1975) – and intended to bring the French rail network to the cutting edge of land-based public transportation. Though similar to a maglev design, which levitates a train car over a complex electromagnetic track to eliminate all resistance other than aerodynamic drag, the Aérotrain – also a "train without wheels" – rode on an air cushion over a simple reinforced concrete track or ''guideway'' and could travel at the speed of a maglev train, without the further technical complexity and expense of its track. In many respects, the entire concept resembled a product of the aircraft rather than rail industry. History In 1969, a U.S. company, Rohr Industries, licensed the Aérotrain technology to build the hovertrains in the United States. That same year the Aérotrain established the world record ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hovercraft
A hovercraft, also known as an air-cushion vehicle or ACV, is an amphibious Craft (vehicle), craft capable of travelling over land, water, mud, ice, and other surfaces. Hovercraft use blowers to produce a large volume of air below the hull, or air cushion, that is slightly above atmospheric pressure. The pressure difference between the higher pressure air below the hull and lower pressure ambient air above it produces lift, which causes the hull to float above the running surface. For stability reasons, the air is typically blown through slots or holes around the outside of a disk- or oval-shaped platform, giving most hovercraft a characteristic rounded-rectangle shape. The first practical design for hovercraft was derived from a British invention in the 1950s. They are now used throughout the world as specialised transports in disaster relief, coastguard, military and survey applications, as well as for sport or passenger service. Very large versions have been used to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otis Hovair
Otis Hovair Transit Systems is a type of hovertrain used in low-speed people mover applications. Traditional people mover systems used wheeled vehicles propelled by electric motors or cable traction, the Hovair replaces the wheels with a hovercraft lift pad. The aim is to reduce guideway complexity and vehicle maintenance. Another benefit is the system's ability to move in all directions, including sideways. The Hovair is the only hovertrain system to be used in commercial service. History Originally developed at General Motors as an automated guideway transit system, GM was forced to divest the design as part of an anti-trust ruling. The design eventually ended up at Otis Elevator who replaced its linear motor with a cable pull and sold the resulting design for people mover installations all over the world. The first installation was the Duke Hospital PRT in 1979, followed by the Harbour Island People Mover opened in 1985. Otis successfully marketed the system through the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hunting Oscillation
Hunting oscillation is a self-oscillation, usually unwanted, about an equilibrium. The expression came into use in the 19th century and describes how a system "hunts" for equilibrium. The expression is used to describe phenomena in such diverse fields as electronics, aviation, biology, and railway engineering. Railway wheelsets A classical hunting oscillation is a swaying motion of a railway vehicle (often called ''truck hunting'' or ''bogie hunting'') caused by the coning action on which the directional stability of an adhesion railway depends. It arises from the interaction of adhesion forces and inertial forces. At low speed, adhesion dominates but, as the speed increases, the adhesion forces and inertial forces become comparable in magnitude and the oscillation begins at a critical speed. Above this speed, the motion can be violent, damaging track and wheels and potentially causing derailment. The problem does not occur on systems with a differential because the action dep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Motor
A linear motor is an electric motor that has had its stator and rotor "unrolled", thus, instead of producing a torque (rotation), it produces a linear force along its length. However, linear motors are not necessarily straight. Characteristically, a linear motor's active section has ends, whereas more conventional motors are arranged as a continuous loop. A typical mode of operation is as a Lorentz-type actuator, in which the applied force is linearly proportional to the current and the magnetic field (\vec F = I \vec L \times \vec B). Linear motors are by far most commonly found in high accuracy engineering applications. It is a thriving field of applied research with dedicated scientific conferences and engineering text books. Many designs have been put forward for linear motors, falling into two major categories, low-acceleration and high-acceleration linear motors. Low-acceleration linear motors are suitable for maglev trains and other ground-based transportation applicat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poppet Valve
A poppet valve (also called mushroom valve) is a valve typically used to control the timing and quantity of gas or vapor flow into an engine. It consists of a hole or open-ended chamber, usually round or oval in cross-section, and a plug, usually a disk shape on the end of a shaft known as a valve stem. The working end of this plug, the valve face, is typically ground at a 45° bevel to seal against a corresponding valve seat ground into the rim of the chamber being sealed. The shaft travels through a valve guide to maintain its alignment. A pressure differential on either side of the valve can assist or impair its performance. In exhaust applications higher pressure against the valve helps to seal it, and in intake applications lower pressure helps open it. The poppet valve was invented in 1833 by American E.A.G. Young of the New Castle and Frenchtown Turnpike and Railroad Company, Newcastle and Frenchtown Railroad. Young had patented his idea, but the 1836 U.S. Patent Offic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modern Mechanix
''Mechanix Illustrated'' was an American printed magazine that was originally published by Fawcett Publications. Its title was founded in 1928 to compete against the older ''Popular Science'' and ''Popular Mechanics''. Billed as "The How-To-Do Magazine," ''Mechanix Illustrated'' (''MI'') aimed to guide readers through various projects from home improvements and advice on repairs to "build-your-own (sports car, telescope, helicopter, etc)." It was headquartered in New York City. History and profile From its debut in 1928, it went through a number of permutations over the years, being called at various points in its life, ''Modern Mechanics and Inventions'', ''Modern Mechanix and Inventions'', ''Modern Mechanix'', ''Mechanix Illustrated'', ''Home Mechanix'', and, in its final incarnation, ''Today's Homeowner''. Although it featured many how-to articles, the most eagerly awaited and read features were Tom McCahill's monthly automobile tests which ran from the late 1940s to the earl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popular Mechanics
''Popular Mechanics'' (sometimes PM or PopMech) is a magazine of popular science and technology, featuring automotive, home, outdoor, electronics, science, do-it-yourself, and technology topics. Military topics, aviation and transportation of all types, space, tools and gadgets are commonly featured. It was founded in 1902 by Henry Haven Windsor, who was the editor and—as owner of the Popular Mechanics Company—the publisher. For decades, the tagline of the monthly magazine was "Written so you can understand it." In 1958, PM was purchased by the Hearst Corporation, now Hearst Communications. In 2013, the US edition changed from twelve to ten issues per year, and in 2014 the tagline was changed to "How your world works." The magazine added a podcast in recent years, including regular features ''Most Useful Podcast Ever'' and ''How Your World Works''. History ''Popular Mechanics'' was founded in Chicago by Henry Haven Windsor, with the first issue dated January 11, 1902. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jet Engine
A jet engine is a type of reaction engine discharging a fast-moving jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include rocket, Pump-jet, water jet, and hybrid propulsion, the term typically refers to an internal combustion airbreathing jet engine such as a turbojet, turbofan, ramjet, or pulse jet engine, pulse jet. In general, jet engines are internal combustion engines. Airbreathing jet engines typically feature a Axial compressor, rotating air compressor powered by a turbine, with the leftover power providing thrust through the propelling nozzle—this process is known as the Brayton cycle, Brayton thermodynamic cycle. Jet aircraft use such engines for long-distance travel. Early jet aircraft used turbojet engines that were relatively inefficient for subsonic flight. Most modern subsonic jet aircraft use more complex High-bypass turbofan, high-bypass turbofan engines. They give higher speed and greater fuel eff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ford Motor Company
Ford Motor Company (commonly known as Ford) is an American multinational automobile manufacturer headquartered in Dearborn, Michigan, United States. It was founded by Henry Ford and incorporated on June 16, 1903. The company sells automobiles and commercial vehicles under the Ford brand, and luxury cars under its Lincoln luxury brand. Ford also owns Brazilian SUV manufacturer Troller, an 8% stake in Aston Martin of the United Kingdom and a 32% stake in China's Jiangling Motors. It also has joint ventures in China (Changan Ford), Taiwan (Ford Lio Ho), Thailand ( AutoAlliance Thailand), and Turkey ( Ford Otosan). The company is listed on the New York Stock Exchange and is controlled by the Ford family; they have minority ownership but the majority of the voting power. Ford introduced methods for large-scale manufacturing of cars and large-scale management of an industrial workforce using elaborately engineered manufacturing sequences typified by moving assembly lines; by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
