Geometry.Net - Science: Magnetic Levitation

Diamagnetic Levitation
The July 22 Nature paper, magnetic levitation at your fingertips, describes two configurationswhere diamagnetic materials are used to stabilize the levitation
http://www.physics.ucla.edu/marty/diamag/

Extractions: Many common materials such as water, wood, plants, animals, diamonds, fingers, etc. are usually considered to be non-magnetic but in fact, they are very weakly diamagnetic. Diamagnets repel, and are repelled by a strong magnetic field. The electrons in a diamagnetic material rearrange their orbits slightly creating small persistent currents which oppose the external magnetic field. Two of the strongest diamagnetic materials are graphite and bismuth. The forces created by diamagnetism are extremely weak, millions of times smaller than the forces between magnets and such common ferromagnetic materials as iron. However, in certain carefully arranged situations, the influence of diamagnetic materials can produce startling effects such as levitation. It was proved in 1842 that it is impossible to stably levitate any static array of magnets by any arrangement of fixed magnets and gravity. However, the addition of diamagnetic materials makes such levitation possible. The July 22 Nature paper, Magnetic Levitation at your fingertips , describes two configurations where diamagnetic materials are used to stabilize the levitation of a magnet in the field of a fixed lifting magnet.
Not A Bird Or Plane, Just Shanghai's New Maglev, The World's Fastest Train
The magnetic levitation train is finally a reality, as reporter Ron Gluckman shows on a test ride on the world's fastest train, in Shanghai.
http://www.gluckman.com/Maglev.html

Extractions: Is it a Bird? A Plane? Nope, only Shanghai's flashy new Maglev, the world's fastest train. Way ahead of its time seven decades ago, the still-futuristic magnetic levitation system may yet redefine travel everywhere. By Ron Gluckman/Shanghai,China L IKE MANY ON THE MAINLAND, I was on the move over the Chinese New Year. My flight lifted off early on the last morning of the Year of the Horse, touching down at the airport eight minutes later. Yet it never left the ground. My flight - that's what it was called - was aboard Shanghai's spanking-new Maglev (magnetic levitation) train, the world's fastest, most futuristic passenger line. Longest-awaited, too, since it's been an astonishing seven decades since the invention of the process that was finally put to a test on the next-to-the-last day of last year, when Premier Zhu Rongji took an inaugural ride with Chancellor Gerhard Schroeder of Germany, which helped fund and build this line. Now, common cadres were having a turn. Local media called them "joyrides," these series of trial runs to the international airport in Pudong , across the river from Shanghai proper, that add a bit of flash to the Spring Festival. They certainly live up to the billing.
Magnetic Levitation
Physics FAQ. Original by Philip Gibbs and Andre Geim, 18March-1997.Is magnetic levitation Possible? A theorem due to Samuel Earnshaw
http://www.hfml.kun.nl/levitation-possible.html

Extractions: [Physics FAQ] Original by Philip Gibbs and Andre Geim, 18-March-1997 A theorem due to Samuel Earnshaw proves that it is not possible to achieve static levitation using any combination of fixed magnets and electric charges. Static levitation means stable suspension of an object against gravity. There are, however, a few ways of to levitate by getting round the assumptions of the theorem. The proof of Earnshaw's theorem is very simple if you understand some basic vector calculus. The static force as a function of position F x acting on any body in vacuum due to gravitation, electrostatic and magnetostatic fields will always be divergenceless. div F . At a point of equilibrium the force is zero. If the equilibrium is stable the force must point in towards the point of equilibrium on some small sphere around the point. However, by Gauss' theorem, F x ).d S F dV /S /V the integral of the radial component of the force over the surface must be equal to the integral of the divergence of the force over the volume inside which is zero. QED! This theorem even applies to extended bodies which may even be flexible and conducting so long as they are not diamagnetic. They will always be unstable to lateral rigid displacements of the body in some direction about any position of equilibrium. You cannot get round it using any combination of fixed magnets with fixed pendulums or whatever.
Magnetic Levitation Haptic Interfaces
MSL MSL Projects - magnetic levitation Haptic Interfaces. magnetic levitationHaptic Interfaces. Using the magnetic levitation Haptic Interaction System,
http://www.cs.cmu.edu/afs/cs/project/msl/www/haptic/haptic_desc.html
Amlev (American Magentic Levitation) Is A Fulfilled Dream Of Engineers.
AMLEV is a high speed transportation system ensuring absolutely stable and safe flight of a vehicle in its own magnetic field with a speed up to 540 km/h (150 m/s) without a servo control system.
http://www.amlevtrans.com

Extractions: Inventor Oleg V. Tozoni AMLEV is a high speed transportation system ensuring absolutely safe and stable flight of a vehicle in its own magnetic field with a speed up to 540 km/h m/s ) without a servo control system. Like a live creature it reacts instantly and faultlessly to any deviation from its position on a projected track or any deflection of the vehicle speed from its given value by producing internal magnetic stabilizing forces sufficient to eliminate such variations. It has been achieved thanks to a special design of Amlev devices: both suspension and propulsion, performed in such a way that resilient magnetic lines in their air gaps work like stretched bowstrings. Amlev is based only on rare-earth permanent magnets and laminated steel cores covered by an aluminum layer. FIG.1 (Click to Enlarge) AMLEV is capable of maintaining levitation force weight of levitated magnets. Permissible lateral pressure is up to 6 t per vehicle of the length 22 m mm.
Magnetic Levitation Haptic Interfaces
magnetic levitation Haptic Interfaces. Peter Berkelman, Zack Butler,and Ralph Hollis. This project advances knowledge about how to
http://www.cs.cmu.edu/afs/cs/project/msl/www/haptic/oldhap.html

Extractions: MSL Projects Magnetic Levitation Haptic Interfaces - Early Work Peter Berkelman, Zack Butler, and Ralph Hollis This project advances knowledge about how to give computer users convincingly real haptic (sense of touch) interaction with computers. While there has been some progress in this area, chiefly through the use of back-driven robotic-like manipulators, this is a substantially new approach which promises a qualitative leap in improvement of such capabilities: A user interacts with the computer by grasping a rigid tool whose behavioral description is computed, employing this tool to interact with computed environments which are semantically meaningful in terms of the application. At the same time, the environment exerts realistic forces and torques on the tool's handle which are felt by the user. The vision is one of providing the computer user immediate, high-fidelity, convincingly real interaction with computed environments. The new haptic interface approach is based on a recently developed magnetic levitation technology, and on recent strong advances in the art of physically-based simulation. The magnetic levitation technology uses Lorentz forces to stably levitate and control a rigid body (which includes the handle through which the user interacts) in six degrees of freedom, giving a new and heretofore unexplored physical basis for haptic interaction.
Boeing: MagLev Homepage
of the magnetic levitation upgrade to the Holloman High Speed Test Track at Holloman Air Force Base, New Mexico.
http://www.boeing.com/defense-space/space/maglev/

Extractions: MagLev More Information MagLev Home Current Activity Division of Work Features Facts Boeing is part of the General Atomics/Bechtel/Foster-Miller team designing and building a magnetic levitation upgrade to the Holloman High Speed Test Track at Holloman Air Force Base , New Mexico. The upgrade is a multiphased effort to provide a Hypersonic Ground Test Facility for the Air Force and the nation. The MagLev system will not only provide important test capability for our national defense, but will also establish many of the design parameters needed to understand this technology's potential for launch assist. That's why Boeing is working to leverage this MagLev technology for the benefit of NASA programs such as the Highly Reusable Space Transportation Phase II study The research reported in this paper was sponsored by the 46th Test Group (AFMC), Holloman AFB, NM, under a Boeing North American, Inc. subcontract through contract F08635-94-C-0016 with General Atomics. Opinions, conclusions, and recommendations contained in this article are those of the author and are not necessarily endorsed by the US Air Force. MagLev Home Current Activities Division of Work Features ... Privacy
Superconductivity Technology Center At Los Alamos
magnetic levitation TRAINS Magnetically levitated (MAGLEV) trainsare considered as a future application of HTS development. To
http://www.lanl.gov/superconductivity/train.shtml

Extractions: Magnetically levitated (MAGLEV) trains are considered as a future application of HTS development. To understand why, we must look briefly at the history of the railroads. The development of trains and rails began in the early 1800s. The modern conventional train is no faster (~110 mph) than those of the late 1890s. So conventional trains have reached the end phase of their development. France, Germany, and Japan have developed "high-speed" or "bullet" trains capable of speeds of 150-180 mph. This improvement in speed is based upon improved rails and controls. However, this technology has also reached the end phase of its development. One limiting factor for these trains is the expensive and time-consuming maintenance of the rails. So it is the mechanical friction between train wheels and metal tracks that limit this technology. This leads us to the development of the magnetically levitated (no friction) trains. We briefly describe the history of this development. The idea of MAGLEV transportation has been around since the early 1900s. The benefit of eliminating the wheel/rail friction to obtain higher speeds and lower maintenance costs has great appeal. The basic idea of a MAGLEV train is to levitate it with magnetic fields so there is no physical contact between the train and the rails (guideways).
Popular Mechanics - Science
Article on Inductrack room temperature magnetic levitation system being developed at LLNL. Date 2000.05.00
http://popularmechanics.com/popmech/sci/9805STTRM.html

Extractions: PM Science Editor Reports Live From Gulf War II, U.S. Central Command DOHA, Qatar, March 21 Sources close to British intelligence say that a tip by a mole in the Iraqi leadership convinced the U.S.-led coalition to delay the start of the ground phase of Gulf War II, to allow time for a hastily planned "decapitation attack" against Saddam Hussein. That attackwhich took place shortly after the 48-hour exile ultimatum issued to Hussein expired at 4:15 am local time on Thursdayfailed. A second cruise-missile attack launched after Saddam Hussein appeared on Iraqi television also failed, but it destroyed several so-called leadership targets in the center of Baghdad. Six reports from the 2003 annual meeting of the American Association for the Advancement of Science. First up, climate-change epidemics A unique monthly feature that digests the lives of famous people who, coincidentally, wrote for POPULAR MECHANICS last century. Dig in
Welcome To The Federal Railroad Administration
magnetic levitation (MAGLEV). magnetic levitation (Maglev) is an advanced technologyin which magnetic forces lift, propel, and guide a vehicle over a guideway.
http://www.fra.dot.gov/rdv/hsgt/maglev.htm

Extractions: Magnetic Levitation Magnetic Levitation (MAGLEV) The MAGLEV Deployment Program In 1998 Congress passed the "Transportation Equity Act for the 21 st Century" making available more than $ 218 billion over a six year period for surface transportation assistance to states and localities. Section 1218 of this Act created a National Magnetic Levitation Transportation Technology Deployment Program. The program is administered by the Federal Railroad Administration (FRA), a unit of the Department of Transportation. The idea behind the program is to demonstrate high speed maglev technology in commercial service through a project of about 40 miles in length, so that it can be considered later in the century for implementation in a longer distance intercity corridor application. As provided for in Section 1218, federal funding consists of $55 million for preconstruction planning to identify the most promising project through a competitive process , and up to $950 million for final engineering and construction of the guideway of the one selected project. The Federal funds for planning and construction must be matched 1/3 to 2/3 by state, local, or private contributions. To be eligible for Federal construction funding, each project must demonstrate that operating revenues will exceed operating costs, and total benefits will exceed total costs over a 40-year period.
ABCNEWS.com : Seven Maglev Train Finalists
Seven projects in seven states are working on developing the nation's first magnetic levitation train. The hope is to reduce congestion with highspeed rail.
http://www.abcnews.go.com/sections/tech/DailyNews/trains990525.html
Magnetic Levitation
magnetic levitation. Magnetic fields are actively excluded from superconductors(Meissner effect). If a small magnet is brought near
http://hyperphysics.phy-astr.gsu.edu/hbase/solids/maglev.html

Extractions: Magnetic Levitation Magnetic fields are actively excluded from superconductors ( Meissner effect ). If a small magnet is brought near a superconductor, it will be repelled becaused induced supercurrents will produce mirror images of each pole. If a small permanent magnet is placed above a superconductor, it can be levitated by this repulsive force. The black ceramic material in the illustrations is a sample of the yttrium based superconductor. By tapping with a sharp instrument, the suspended magnet can be caused to oscillate or rotate. This motion is found to be damped, and will come to rest in a few seconds. Cube Movie 1 Cube Movie 2 Cylinder Movie Illustration of the damped motion ... Condensed Matter R Nave Go Back Levitation Currents The Meissner effect in superconductors like this black ceramic yttrium based superconductor acts to exclude magnetic fields from the material. Since the electrical resistance is zero, supercurrents are generated in the material to exclude the magnetic fields from a magnet brought near it. The currents which cancel the external field produce magnetic poles which mirror the poles of the permanent magnet, repelling them to provide the lift to levitate the magnet The levitation process is quite remarkable. Since the levitating currents in the superconductor meet no resistance, they can adjust almost instantly to maintain the levitation. The suspended magnet can be moved, put into oscillation, or even spun rapidly and the levitation currents will adjust to keep it in suspension.
Magnetic Levitation
A small rareearth magnet is suspended above a yttrium based superconductor whenthe Magnetic field is actively excluded from the superconductor (Meissner
http://hyperphysics.phy-astr.gsu.edu/hbase/solids/maglev5.html

Extractions: Damping of Levitated Magnet Motion A small rare-earth magnet is suspended above a yttrium based superconductor when the Magnetic field is actively excluded from the superconductor ( Meissner effect ).The tiny magnet can be caused to spin by tapping it with a small instrument such as the tip of tweezers. Even though the magnet is continuously suspended, this rotational motion is damped. The rotation will slow down and it will go into a rocking mode and finally come to rest. The magnet is suspended over the superconductor by immersing the superconducting disc in liquid nitrogen (77K). The induced currents in the superconductor mirror the poles of the magnet and adjust so quickly that the magnet can be translated or rotated and remain suspended. Experimenters: Darren Vick and Steven Gabriel The damping of the oscillatory motion of the levitated magnet was investigated by taking digital video of the motion and converting it to a Quicktime movie. Measurements from the Quicktime movie were made at 1/30 sec intervals using VideoPoint. The data was transferred to an Excel spreadsheet to make the plots. For a first approximation, the motion could be modeled as a damped sine wave Analysis of the damping in the illustration above gives a damping coefficient of 0.247. This number was obtained by doing a least-squares fit of the peaks of the damped oscillation. Closer examination reveals that the period of the damped motion is changing, as illustrated below.
Magnetic Levitation
Updated 8September-1997 by PEG Original by Philip Gibbs and AndreGeim, 18-March-1997. Is magnetic levitation Possible? A theorem
http://math.ucr.edu/home/baez/physics/General/Levitation/levitation.html

Extractions: Original by Philip Gibbs and Andre Geim, March 1997. A theorem due to Earnshaw proves that it is not possible to achieve static levitation using any combination of fixed magnets and electric charges. Static levitation means stable suspension of an object against gravity. There are, however, a few ways to levitate by getting round the assumptions of the theorem. In case you are wondering, none of these can be used to generate anti-gravity or to fly a craft without wings or jets. The proof of Earnshaw's theorem is very simple if you understand some basic vector calculus. The static force as a function of position F x acting on any body in vacuum due to gravitation, electrostatic and magnetostatic fields will always be divergenceless. div F . At a point of equilibrium the force is zero. If the equilibrium is stable the force must point in towards the point of equilibrium on some small sphere around the point. However, by Gauss' theorem, F x ).d
Visual Levitation - Magnetic Levitation And Suspension
Available Now Click Here. Unique magnetic levitation devices, with patented 2 ampmagnetic suspension technology, objects up to 3kg float in mid air.
http://www.visuallevitation.com/
Visual Levitation - Magnetic Levitation And Suspension
Marketing of unique levitation devices patented 2 amp magnetic suspensiontechnology, objects up to 3kg float in mid air.
http://www.visuallevitation.com/DesignGallery1.htm
Robotics Institute: Magnetic Levitation Haptic Interfaces
Text only version of this site. magnetic levitation Haptic InterfacesHead Ralph Hollis Contact Ralph Hollis (rhollis@cs.cmu.edu)
http://www.ri.cmu.edu/projects/project_111.html

Extractions: Associated lab/group: Microdynamic Systems Lab For more information, see this project's homepage This page last updated - January 1999. Jump to: Project Description Personnel Publications Project Description This project advances knowledge about how to give computer users convincingly real haptic (sense of touch) interaction with computers. While there has been some progress in this area, chiefly through the use of back-driven robotic-like manipulators, this is a substantially new approach which promises a qualitative leap in improvement of such capabilities: A user interacts with the computer by grasping a rigid tool whose behavioral description is computed, employing this tool to interact with computed environments which are semantically meaningful in terms of the application. At the same time, the environment exerts realistic forces and torques on the tool's handle which are felt by the user. The vision is one of providing the computer user immediate, high-fidelity, convincingly real interaction with computed environments. Personnel Past Members Name Title Email Address Ralph Hollis Principal Research Scientist rhollis@cs.cmu.edu
Robotics Institute: Magnetic Levitation Haptic Interfaces
Graphics enhanced version of this site. magnetic levitation Haptic InterfacesHead Ralph Hollis Contact Ralph Hollis (rhollis@cs.cmu.edu).
http://www.ri.cmu.edu/projects/project_111_text.html

Extractions: Associated lab/group: Microdynamic Systems Lab For more information, see this project's homepage This page last updated - January 1999. Jump to: Project Description Personnel Publications Project Description This project advances knowledge about how to give computer users convincingly real haptic (sense of touch) interaction with computers. While there has been some progress in this area, chiefly through the use of back-driven robotic-like manipulators, this is a substantially new approach which promises a qualitative leap in improvement of such capabilities: A user interacts with the computer by grasping a rigid tool whose behavioral description is computed, employing this tool to interact with computed environments which are semantically meaningful in terms of the application. At the same time, the environment exerts realistic forces and torques on the tool's handle which are felt by the user. The vision is one of providing the computer user immediate, high-fidelity, convincingly real interaction with computed environments. Personnel Past Members Publications Note : This list may not be comprehensive. It contains only those publications in the RI publications database. Entries are listed in reverse chronological order.
MAGNETIC LEVITATION STIRRERS
magnetic levitation Stirrers (US patent 6,357,907) were designed to stir the tallnarrow columns of deep well 96 and the new Whatman Polyfiltronics deep well
http://www.vp-scientific.com/magnetic_levitation.htm

Extractions: Simple to operate The gold standard for optimal bacterial growth is aeration using a shake flask on an orbital shaker. Unfortunately deep well blocks (96 or 384) are not aerated like the flasks are on the orbital shaker and the growth fades when the oxygen in the media is depleted. One of our customers compared E. coli growth using Levitation Stirring in 96 deep well blocks and a shake flask on an orbital shaker the results below demonstrated comparable growth curves between the two culture conditions. Thus it possible to obtain maximal DNA or protein yields in miniaturized culture conditions. INCUBATION TIME LEVITATION STIRRER OD SHAKE FLASK OD hour 1 hour 2 hours 3 hours 4 hours 5 hours 6 hours LEVITATION STIRRING VISCOUS SOLUTIONS For comparison 1 centistoke = 1.0760 x 10E-5 sq. ft./sec.
TEA-21 - Fact Sheet: Magnetic Levitation Transportation Technology Deployment Pr
magnetic levitation TRANSPORTATION TECHNOLOGY DEPLOYMENT PROGRAM. Year. 1997.1998. 1999. 2000. 2001. 2002. 2003. Contract Authority. 0. 0. $15M. $20M. $25M.0. 0.
http://www.fhwa.dot.gov/tea21/factsheets/r-maglev.htm

Extractions: (subject to appropriation) Program Purpose The magnetic levitation transportation technology deployment program encourages the development and construction of an operating transportation system employing magnetic levitation capable of safe use by the public at a speed in excess of 240 miles per hour. [1218] Funding Features Contract authority out of the Highway Account of the Highway Trust Fund is provided for fiscal years 1999-2001 totaling $60 million. An authorization for an appropriation out of the Highway Account of the HTF is provided for an additional $950 million over fiscal years 2000-2003. These funds would have to be appropriated by the Congress before they would be available for expenditure. An eligible maglev project would also be eligible for other forms of financial assistance provided in Title 23, United States Code, and TEA-21, including loans, loan guarantees, and lines of credit. [1218]

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