Build Your Own Arcade Controls Forum
Main => Everything Else => Topic started by: shorthair on June 08, 2007, 12:33:28 pm
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From what I know of Telsa, I think this isn't any different a concept than what his was. To him, resonance wasn't segmented by application or medium. It was all the same thing, and he had both electro-magnetic and mechanical devices. And as far as the statement about high voltage being involved, well, back then they're stuff was crude and large. Duh. It's going to get more interesting.
Wireless power a reality
7 June 2007
The mess of electrical cables that recharge our laptops, mobile phones and PDAs could soon disappear altogether -- at least according to a team of US physicists, who have shown how power can be transmitted without wires using special "resonant" antennas. The researchers used the system to power a 60-W light bulb placed two metres from a wireless transmitter, and say that it could be scaled down for use in portable devices without a loss of efficiency (Science Express doi: 10.1126/science.1143254).
Power without wires isn't a new concept – in the early 1900s before electricity grids were established, the Serbian inventor Nikola Tesla envisioned a world of wireless power using a network of high-voltage "Tesla coils". Although his scheme didn't catch on because of the dangerously large electric fields involved, recent proposals of wireless power employing radiation from a transmitter have begun to rekindle interest. Unfortunately, those that have relied on transmitters emitting in all directions have been too inefficient, and those that have opted for unidirectional transmitters have been impractical for most applications because they need a clear line of sight between transmitter and receiver.
A power of good
Last year, physicists at the Massachusetts Institute of Technology (MIT) proposed a way to avoid these problems by employing non-radiative "evanescent" electromagnetic waves. These waves are usually generated in addition to the familiar radiative waves used in wireless communications, but decay very quickly as they extend from an antenna. Marin Soljacic and colleagues thought that if the receiver could resonate with the transmitter, the evanescent field would instigate a current between the two. In this way, non-resonant objects placed in the field would neither interrupt the signal nor absorb much of the field's energy (see related story: "Gadget recharging goes wireless").
Now, Soljacic's team have put their idea into practice. Using their theory, they have created a pair of ring-shaped copper antennas. One of these they connected to an electricity supply, while the other they connected to a 60-W light bulb placed two metres away. When they ran an oscillating current through the first, it produced a magnetic field that "resonantly coupled" to the second, thus inducing a current. This current, the MIT team claim, fully lit the bulb with a transmission efficiency of 40%, just as their theory predicted.
Although the antennas demonstrated were over half a metre in diameter, Soljacic and co-workers say that scaled-down versions of the system could be made for portable devices without sacrificing efficiency. This might also enable the design of electronic medical implants that do not need cumbersome wiring.
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GI Joe solved that. Don't you remember the Broadcast Energy Transmitter?
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Which one? I wasn't all that into Joe, though more so in the 80s incarnation, and all I remember was the mass something device they used to teleport around with in the pilot series.
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From the Movie, that's what Cobra was trying to capture, when Serpentor was captured and Cobra became Cobra-LA (and Cobra Commander's origin was revealed).
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http://www.thinkgeek.com/stuff/41/wec.shtml
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From the Movie, that's what Cobra was trying to capture, when Serpentor was captured and Cobra became Cobra-LA (and Cobra Commander's origin was revealed).
I wasn't that into later Joe, either...though I do recall seeing the movie where Serpentor was created. Really, anything that people didn't die in got left quick. Robotech was very welcome. Not much later, I'd dropped any American animation and comics for anime and manga (Appleseed, Xenon, anything with more life-like attributes - Akira was killer animation but I wasn't hot on the story).
AS: oh sure, there's microwave - but like the article says, it and everything else requires line-of-sight.
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AS: oh sure, there's microwave - but like the article says, it and everything else requires line-of-sight.
Actually that product was an April Fools joke (try to buy one), this thread just reminded me of it.
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...Cobra-LA...
Is that Louisiana or Los Angeles?
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There's a company thats already been doing this and will start late this year selling it to commercial places
Good work on MIT tho :)
I love telsa he really was a great man just never gets much credit
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...Cobra-LA...
Is that Louisiana or Los Angeles?
Neither, it's an evil-military utopia... like Shangri-La.
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its TESLA
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One of the best concerts I have ever been to. They ROCKED! :notworthy: :notworthy: :applaud: :applaud:
J_K_M_A_N
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CHUN-CHUN CHUN, CHUN-CHUN CHUN, AOOOOOHHHHHHHHH . Needed a little metal relief, there.
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I just picked up their new album Real to Reel and its a really good album. The covered a bunch of classic rock songs and gave them just a bit of a heavy metal feel, which works really well.
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....heavy metal. No, I meant like XM's liquid metal: 'LI-QUID FU-&*ING ME-TAL'. I mean some of Journey's latest stuff is some of their best, but rock was basically sitting taking a crap from 83-84 till just a few years ago.