Design principles for magnetic levitation

Thornton, R.D.

doi:10.1109/proc.1973.9115

Cited by 26 publications

(5 citation statements)

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“…At high speeds the low inherent damping coefficient of the suspension or guidance further reduces and in fact can become negative, presenting some quite serious problems of vehicle stability in general. It has been reported that passive damping may be inadequate , Thornton 1973, Qhno et a1 1973, Coffey et a1 1969. If a linear synchronous motor is used as propulsion unit, a proposal to vary the drive to the motor in accordance with the vertical acceleration signals fed back (Greene 1974) or variation of coil currents (Ooi and Banakar 1975) to produce more damping at the expense of the figure of merit have been considered.…”

Section: Levitation Using Superconductorsmentioning

confidence: 99%

“…The other project, called the magnaplane project, was partly under the direction of the National Science Foundation. Both studies were theoretical as well as experimental but involving permanent magnets (Thornton 1973, Ooi and Banakar 1975, Tang et a1 1975, Reitz and Borcherts 1975. Research in the United States appears to have been halted indefinitely since about 1975.…”

Section: Levitation Using Superconductorsmentioning

confidence: 99%

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Electromagnetic suspension and levitation

Jayawant

1981

Rep. Prog. Phys.

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The phenomenon of levitation has attracted attention from philosophers and scientists in the past. The recent advances, notably in power electronics and magnetic materials, have focused this attention within the last decade on the application of electromagnetic suspension and levitation techniques to advanced ground transportation. Regardless of the fact that there is, in effect, a separate technology involved for each electromagnetic method, the whole subject is given a blanket title of 'maglev'. There is also a very wide range of industrial applications to which magnetic suspension techniques could be profitably applied, particularly in the area of high-speed bearings to reduce noise and to eliminate friction, and yet only high-speed ground transportation has caught the imagination of the media. This review deals with the physics and engineering aspects of the four principal contenders for advanced ground transportation systems and describes the most up-to-date developments in Germany, Japan, USA and the UK in this field. This article also describes some of the very recent challenging developments in the application of electromagnetic suspension and levitation techniques to contactless bearings. A fairly comprehensive bibliography is given to enable the more interested reader to pursue the topic further in any one of the technologies dealt with in this review.

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Section: Levitation Using Superconductorsmentioning

confidence: 99%

Section: Levitation Using Superconductorsmentioning

confidence: 99%

Electromagnetic suspension and levitation

Jayawant

1981

Rep. Prog. Phys.

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“…Proposals have also been made to use the tower as a linear induction propulsion system that would recover energy from a descending capsule and reuse the energy later to propel a capsule up the tower. 11 A second major application of the elevator is to use the tower's rotational energy to launch spacecraft on orbits that would allow them to reach other planets. An object released from rest from a point sufficiently high up on the tower would be able to escape the Earth's gravity and sail away to infinity.…”

Section: Applications: Launching Payload Into Orbit and Spacecraftmentioning

confidence: 99%

The physics of the space elevator

Aravind

2007

American Journal of Physics

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A space elevator is a tall tower rising from a point on the Earth's equator to a height well above a geostationary orbit, where it terminates in a counterweight. Although the concept is more than a century old, it was only with the discovery of carbon nanotubes that it began to receive serious scientific attention. NASA commissioned a study of the space elevator in the late 1990s that examined the feasibility of such a structure and explored many of its applications. I explain the basic mechanical principles underlying the construction of a space elevator and discuss several of its applications: the transport of payload into space and the launching of spacecraft on voyages to other planets.

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“…Solve (11.10) and (11.11) simultaneously to obtain Yip » nondimensionalize, and substitute (11. 19) to obtain the open loop equations of motion:…”

Section: 3 Non-optimal Situationsmentioning

confidence: 99%