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MIT Wirelessly Powers a Lightbulb
Posted by
Zonk
on Thu Jun 07, 2007 05:51 PM
from the magic-tubes-and-pots-and-pans-bits-and-pieces-and dept.
from the magic-tubes-and-pots-and-pans-bits-and-pieces-and dept.
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.'"
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Burnt out... (Score:5, Funny)
Nothing for you to see here. Please move along.
Apparently the power supply failed.
Mmmmmm...wireless (Score:5, Funny)
Re:Mmmmmm...wireless (Score:5, Funny)
Re:Mmmmmm...wireless (Score:5, Funny)
Induction? (Score:5, Insightful)
Re:Induction? (Score:5, Funny)
Chiefly by the differentiating degree of buzzword compliance.
Re:Induction? (Score:5, Informative)
This is great! (Score:5, Funny)
Re:This is great! (Score:5, Funny)
Are you retarded? Seriously, are you retarded? You want LESS reason to interact with hip coffee shop girls who also happen to have enough cash to buy a Mac? And geeks wonder why they never get laid.... sheesh!
Not the first remotely powered lightbulb (Score:5, Informative)
http://www.boxyit.com/r/index.htm [boxyit.com]
Wow. 100 years and they finally caught up with... (Score:5, Insightful)
Re:Wow. 100 years and they finally caught up with. (Score:5, Insightful)
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.
Re:Wow. 100 years and they finally caught up with. (Score:5, Informative)
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].
They should make me the editor (Score:5, Funny)
The successful experiment to lit a 60-watt light bulb
It should be "to lite a 60-watt light bult." Duh?
Large deal... (Score:5, Interesting)
40% efficiency (Score:5, Insightful)
Why this is important. (Score:5, Informative)
In short, this is NOT the same as holding a flourescent tube under a high voltage powerline. The MIT method uses controlled power tranmission over larger distances (2m or 6ft). The technique uses resonance frequency but has 40% loss, which is very bad meaning it is only 60% efficient. Many modern PSU (Power Supply Units) are 90%+ efficient. Unless they increase the efficiency, the power industry probably won't be jumping on board anytime soon.
tag 'cancer' (Score:5, Funny)
(;
Re:Cancer.. (Score:5, Funny)
Re:Cancer.. (Score:5, Interesting)
Proof positive in my book that women are the result of genetic damage.
I'm sure the power requirements are much lower, but yeah it's all about power level and exposure time. It could be handy for things that normally don't have anyone around, like runway lights that could light up with application forward looking radar or maybe something on the highway that could take advantage of the various auto-braking systems that are finding their way onto cars and trucks.
Actually, this solves the immigration issue. (Score:5, Interesting)
What surprised me was the lack of imagination in the applications. They were talking about remotely recharging cell phones and MP3 players or letting you move around electronics without needing to find a plug. Well those are all fine ideas and quite obvious indeed but I saw nothing about the one area that seemed to potentially benefit the most from this: robotics.
All the pieces are there in robotics except for the one that this technology addresses: lightweight, high-density power. Oh, and let's not forget cheap.
Powering the lights without wires is a fine thing to do. I'm all for it. But what is the high energy deensity application that absolutely requires mobility? It seems to me that there is one in particular and that is robotics.
Moreover, this technology has a limitation of range that actually becomes a feature when applied to robotics. As we know all too well in the age of Iragi battle drones Asimov's laws of robotics are a fantasy relic of a time that couldn't imagine how software would really develop. The truth is, robots can be dangerous and this kind of technology effectively puts a leash on their range. They can do whatever within the home, but they can't just go out and go for a walk. It's a classic example of a limitation becoming a feauture.
So how would it solve the immigration issue?
I just mentioned this range limitation. So then, how could we use this for agricultural robots that would alleviate the need for low paid illegal immigrant farm labor? No problem. Obviously tractors bring their own power sources into the field. So, power in the field is not a problem. You would simply have gangs of robots attatched to resonant inductor power modules hanging off arms of the tractor. Say each tractor controls six platoons of robotic field hands with six resonant inductor orbs. They could work twenty four hours shifts. One tractor and labor gang could harvest dozens of farms per season in a timely manner.
If you need higher power, that's not a problem. There's no reason this technology is limited to 110volts. You can use 600V or 1200V. As much as you need. Your robotic workers would be as powerful as necessary.
Not only would it eliminate the need for foreign labor, it would also reduce the need to use high impact farming techniques such as posioning the soil with bromide gas and laying down plastic mulch. These things are done in the name of economy because it's too expensive to have human labor go through a farm and pick weeds. Monocrops are also planted for the same economic considerations. By dramatically shifting the labor equation you would enable a vast increase in the use of organic farming techniques.
The implications of this technology are far more revolutionary than re-charging an MP3 player.
No, it doesn't. (Score:5, Insightful)
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.
Re:so if cellphone radiation might cause cancer... (Score:5, Insightful)
Re:so if cellphone radiation might cause cancer... (Score:5, Informative)
The intense fields generated in MRI present more immediate and sometimes less manageable risks than cancer.
An MRI magnet can pull a stray hairpin across the room at 40 miles per hour. Hemostats, scissors, wheelchairs, patient gurneys, intravenous poles, and defibrillators have all been turned into projectiles capable of severe harm. When nonmedical people enter the magnet room, things can get even worse. In one instance, a police officer's gun discharged as it was sucked out of his grip; in another, a firefighter was trapped and nearly suffocated as he was drawn into the bore when the breathing apparatus strapped to his back became magnetized in the MRI room.
The phenomenon by which metal becomes spontaneously magnetized is ferromagnetism, which affects iron, nickel, cobalt, and many other familiar metals and alloys. Although most implants today are made with titanium or other nonferromagnetic metals, it's common knowledge that MRI systems can affect older angio and cerebral clips, bone pins, dental work, and even some tattoo dyes. That's the key reason patients are screened. What's less recognized is how MRI scanners may interfere with devices such as pacemakers, pulse oximeters, automated defibrillators, cardiac monitors, insulin pumps, cochlear implants, and vagus and other neurological stimulators.
Where a CT installation's lead shielding is designed to keep radiation inside, MRI shielding keeps stray radiowaves out. The focus is on protecting the magnet from interference, not the other way around.
Plate steel is the only physical material that can contain an MRI system's magnetic field. The lines of force penetrate brick, wood, concrete, cement--which means that not only people outside the MRI suite but even people and machines outside the building can be affected. Any steel in the building construction reshapes the magnetic fields in the MRI, and MRI magnetizes the steel in the building. So the levels of complexity are several orders of magnitude greater than a CT, even though they may not look all that different on the floor plan. Current designs using plate shielding, however, usually are not equipped to deal with the newest crop of 3 Tesla (3T) commercially available systems--and even higher-powered research magnets.
MRI magnets have been known to affect gamma cameras, nuclear medicine hot labs, PET/CT scanners, and other equipment--even those sited at what seems a reasonable distance. The extraordinary sensitivity of today's [imaging] systems--the same feature that makes them so valuable--makes them vulnerable to such disruptions. You don't want to expose them to anything significantly above normal. Basically, any magnetic force stronger than the one that makes a compass point north can disrupt or degrade some types of this equipment. MRI Facility Safety -- Understanding the Risks of Powerful Attraction [radiologytoday.net]
Re:Losses? (Score:5, Interesting)
I wonder how well it takes to moving objects. Such a system could be a boon for moving us toward grid-powered electric vehicles if there were regular transmission coils embedded in heavily-trafficked roads, and they'd be a lot closer to the car than 7 feet, so they'd probably get much higher effiency numbers (perhaps even comparable to battery charge/discharge losses).