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MIT Wirelessly Powers a Lightbulb
kcurtis writes "According to the Boston Globe, MIT Researchers have powered a light bulb remotely. The successful experiment lit a 60-watt light bulb from a power source two meters away, with no physical connection between the power source and the light bulb. Details about WiTricity, or wireless electricity, are scheduled to be reported today in Science Express, the advance online publication of the journal Science, the Massachusetts Institute of Technology said. 'The team from MIT is not the first group to suggest wireless energy transfer. Nineteenth-century physicist and engineer Nikola Tesla experimented with long-range wireless energy transfer, but his most ambitious attempt - the 29m high aerial known as Wardenclyffe Tower, in New York - failed when he ran out of money. Others have worked on highly directional mechanisms of energy transfer such as lasers. However, unlike the MIT work, these require an uninterrupted line of sight, and are therefore not good for powering objects around the home.'"
I want a wireless lightbulb hanging above my head, for when I have good ideas.
No longer having to search for an ethernet cable or phone jack for my modem was great! In a few years, I won't have to battle against the hippie-chick mac users in the coffee shop for one of the tables next to one of the three electrical outlets in the joint! The only problem is, I wouldn't call my computer a, "lap top," anymore, as I wouldn't want to put any device that is recharged wirelessly anywhere near my, ... um,... "equipment."
This isn't really the first lightbulb to be lit remotely. Flourescents can be lit by an EM field.... so in a microwave, or under highpower lines:
http://www.boxyit.com/r/index.htm
Ash nazg durbatuluk, ash nazg gimbatul, ash nazg thraktuluk agh burzum-ishi krimpatul.
Chiefly by the differentiating degree of buzzword compliance.
I'm tired of mistakes like this:
The successful experiment to lit a 60-watt light bulb
It should be "to lite a 60-watt light bult." Duh?
Apology to Ubuntu forum.
I don't know about cancer, but I'll wager standing in the way of a very high power transmitter would probably negate the need for condoms, or possibly skin.
The world's burning. Moped Jesus spotted on I50. Details at 11.
nah, there are enough people imagining this sort of garbage. Let's try studying it instead. MRI uses huge magnetic fields that researchers are exposed to on a daily basis and there is no solid data that it causes biologic harm. All waves that are invisible are not Roentgen's, let's be prudent rather than luddite.
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Hell, back in the 60s, I had a monstrous WWII surplus transmitter, a BC-610 by name. This thing was the size of a large washing machine, and had vacuum tubes in it the size of your head. It would produce a vertiable torrent of RF. As a young ham operator, I was a little sketchy on the principles and practice of proper antenna load and impedance matching, so the whole feedline was radiating, and causing standing waves in all of the house wiring...in my house and the houses around ours. Enough power was intercepted by house wiring that the incandescent bulbs in light fixtures would glow dimly when I was on the air...even though they were turned off. You could hear my voice on telephones for approximately 10 houses radius, since non-linearities in the old phones were enough of a rectifier to do AM detection on the signal the phoen wiring picked up. Fluorescent tubes in my house & my immediate neighbours would light with a strange plasma looking pattern, caused by the structure of the standing waves present. And forget watching TV or listening to the radio in the neighborhood - my voice was heard on radios louder than the program material, and TV pictures were obliterated by a dancing pattern of hum bars. Enough complaining got back to my parents that I could only operate late late late at night....anyway, you can see why I am not that impressed with the concept of wireless power transmission...I did it in person over 40 years ago...
There is no God, and Dirac is his prophet.
First off, Nicola Tesla was not insane. Secondly, he *did* do this, many times in fact.
Personally, I am a bit miffed at the MIT folks for not giving credit where credit is due. This is the second article I have seen in the last month or two on this topic and they hardly even mention the fact that this is a key Tesla invention that was in fact accomplished by him and repeatably demonstrated. To read the articles one would think that the folks at MIT just sat down last week and invented this all by themselves when it is simply not true.
It *is* the case that Tesla is a "fan favorite" of the same type of folks that like to believe in free energy machines and it *is* the case that his *commercial* attempt at providing wireless power was never finished, but the technique and the methodology behind it was sound and I think even patented by Tesla.
To ignore his achievements, simply because many years after his death the man has gained some tertiary association with the lunatic fringe is a bit outrageous to my mind. The particular article referenced here even goes out of it's way to say that Tesla tried wireless power but "failed" (even though they mention off-handedly that it was only through lack of funds, not through any technical problems).
Tesla invented this technique, plain and simple. And those articles that fail to mention it are doing history a great dis-service.
The summaries really should explain these things, I hate having to RTFA. From TFA: At first glance, such a power transfer is reminiscent of relatively commonplace magnetic induction, such as is used in power transformers, which contain coils that transmit power to each other over very short distances. An electric current running in a sending coil induces another current in a receiving coil. The two coils are very close, but they do not touch. However, this behavior changes dramatically when the distance between the coils is increased. As Karalis, a graduate student in electrical engineering and computer science, points out, "Here is where the magic of the resonant coupling comes about. The usual non-resonant magnetic induction would be almost 1 million times less efficient in this particular system."
Frosty piss posts are worthless, GNAA posts are worthless and hurtful, but they are the least of this site's neuroses.
Personally, I am a bit miffed at the MIT folks for not giving credit where credit is due. This is the second article I have seen in the last month or two on this topic and they hardly even mention the fact that this is a key Tesla invention that was in fact accomplished by him and repeatably demonstrated. To read the articles one would think that the folks at MIT just sat down last week and invented this all by themselves when it is simply not true.
p df
The opening paragraph of their earlier paper:
http://arxiv.org/ftp/physics/papers/0611/0611063.
In the early days of electromagnetism, before the electrical-wire grid was deployed, serious interest and effort was devoted (most notably by Nikola Tesla [1]) towards the development of schemes to transport energy over long distances without any carrier medium (e.g. wirelessly). These efforts appear to have met with little success. Radiative modes of omni-directional antennas (which work very well for information transfer) are not suitable for such energy transfer, because a vast majority of energy is wasted into free space. Directed radiation modes, using lasers or highly-directional antennas, can be efficiently used for energy transfer, even for long distances (transfer distance LTRANSLDEV, where LDEV is the characteristic size of the device), but require existence of an uninterruptible line-of-sight and a complicated tracking system in the case of mobile objects. Rapid development of autonomous electronics of recent years (e.g. laptops, cell-phones, house-hold robots, that all typically rely on chemical energy storage) justifies revisiting investigation of this issue. Today, we face a different challenge than Tesla: since the existing electrical-wire grid carries energy almost everywhere, even a medium-range (LTRANS fewLDEV) wireless energy transfer would be quite useful for many applications. There are several currently used schemes, which rely on non-radiative modes (magnetic induction), but they are restricted to very close-range (LTRANSLDEV) or very low-power (~mW) energy transfers [2,3,4,5,6].
As someone with a robotics degree from Carnegie Mellon, I feel to compelled to point out that you're ignoring just how abjectly stupid and incompetent robots still are. We do not have anywhere near the level of AI needed for robot farmers to deal with the messy, filthy, ever-changing world of a farm. Automatic tractors that can plow fields or spray crops, yes. Weeding and picking fruit, no. Power isn't the problem; intelligence is.
There is so much negativity in the air tonight!
Tsunami -- You can't bring a good wave down!
Tesla would be shaking his head in disgust.
do a wiki lookup on the "earth battery"; after that, jump over to "Wardenclyffe".
People really need to stop thinking that hertzian waves are the only thing under the sun.
Why, yes, I AM a Pagan Libertarian.
Have we considered, possibly, perhaps, maybe just, that with greater research this technology could improve over time?
Nah, that's silly!