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Physicists Promise Wireless Power
StrongGlad writes "The tangle of cables and plugs needed to recharge today's electronic gadgets could soon be a thing of the past. Researchers at MIT have outlined a relatively simple system that could deliver power wirelessly to devices such as laptop computers or MP3 players. In a nutshell, their solution entails installing special 'non-radiative' antennae with identical resonant frequencies on both the power transmitter and the receiving device. Any energy not diverted into a gadget or appliance is simply reabsorbed. The system currently under development is designed to operate at distances of 3 to 5 meters, but the researchers claim that it could be adapted to factory-scale applications, or miniaturized for use in the 'microscopic world.'"
... and the subsequent and inevitable lawsuits brought about by people convinced that the wireless power technology is giving them cancer would probably get a little tiresome.
Eviscerati.Org: All Hail the Eviscerati
Umm..
hello.. Tesla??
ever hear of that guy??
yea.. he proposed this well.. 100 years ago..
incidently.. the security word in the image.. photon.. how appropriate..
I bet I'm not the only one here who has taken the piss out of someone for asking if they can get a wireless power supply for their laptop
http://rareformnewmedia.com/
Three Cheers for Nikola Tesla!
This would bring an entirely new scale of issues. People getting arrested for wireless power theft would be cute.
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I can't see
that's why you're not a genius.
Actually, the ironic thing is, if this is using Tesla's principles, it's extremely efficient. Maybe not as much as copper wire, but still rather higher than would be expected.
34486853790
Connection too slow for X forwarding? Try "ssh -CX user@host"
now the people driving around in vans stealing my wireless don't even have to stop to recharge their laptops.
... there might be health issues -- but I suspect there will be lawsuits whether there are health issues or not.
Eviscerati.Org: All Hail the Eviscerati
be best suited for low power applications. Charging a cell phone or palm pilot for example. I mean, I don't see this working for my 500watt computer or my xbox 360. It might charge the controller for my 360, but it would really only get rid of maybe 2 cables behind my computer.
You mad
This is using frequency resonation, Tesla's system didn't.
Think about it this way.
Lets use sound.. Lets say I make a crystal that vibrates at an exact sound frequency, I can make that frequency sound causing no harm to anyone but that crystal, which will vibrate, and potentially break with intense exposure to the sound. Now of course making a sound intense enough to to shatter the crystal and at the same time cause no harm to ones ears is difficult but its possible.
Now do this with electromagnetic waves. The real trick is figuring out how not to waste energy pumping it out in all directions. But its about as dangerous as me sitting here 1000 feet from a major radio broadcast station.....
This thing is supposed to transmit at 6.4MHz. Searching for 6.4Mhz on Google brings back many many links about devices for which that frequency is important. And we wouldn't just be talking about a little bit of radio interference. This would be high power interference.
tesla promised not only wireless power, but also death ray. could you make sure you deliver that to?
thanks!
signed,
technology historians for the realization of past promises
ps: don't think we've forgotten about those rocket cars mr. popular science!
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
What would happen if these were used on highways to power electric cars? Batteries still only return a tenth of the energy put into charging them, so directly conveying power to automobiles would be interesting indeed.
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I guess truth CAN be stranger than fiction.
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___ I don't respond to Anonymous Cowards, and I Never Mod them UP.
...welcome our new tumor causing overlords!
-"...bad old ideas look confusingly fresh when they are packaged as technology" - Jaron Lanier (Digital Maoism on Edge.o
This sounds so much like one of the first Sci Fi books I ever read in high school called, "Microscopic gods" (or was it "Microcosmic gods"?) -- I think it was. A scientist creates microscopic evolution. He keeps experimenting, forcing "stresses" on the creatures to make them evolve. They eventually become sentient, intelligent, creative. To fund his research he invents wireless power. A congressman hooks up with him and uses subterfuge to wrist the new power invention from him. Meanwhile, his microscopic gods keep evolving until they are more advanced than the scientist himself. They refer to him as their "father" or "god" or something. The congressman sends in the military, using the wireless power, to take over the scientist's lab and even washington I think. The scientist sends a request to his creatures to invent an invulnerable forcefield to withstand the attack. They do so, but make it only big enough to cover their little area. He cannot contact them. They send him a -- for the first time ever -- message humbly asking if the parameters were right since they suspected he could not reach them. They also provide the means for him to communicate back. He tells them to increase the size to cover his island and they do. All the planes using the wireless power to take over the country crash, and senator is fouled and the scientist lives happily ever after in his grey, dome, shelled, island with his little gods. The story ends stating the military continues to use the dome for target practice....
"All great things are simple & expressed in a single word: freedom, justice, honor, duty, mercy, hope." --Churchill
Even cell phones are proved to cause cancer...
No, they're not. Cellular phones don't emit ionizing radiation, all their communications happen in the microwave band. This is not powerful enough to cause cell damage on its own. The thermal effects raise cell temperature a fraction of a degree on the surface of the head (an order of magnitude less than the change experienced by standing in sunlight), and the non-thermal effects show no rigorous evidence of genetic damage. Now, near a base station, the situation is a little different, but don't try to scare John Q. Citizen with unfounded FUD about cellular phones causing cancer.
More info here.
There is no mod option "-1: Disagree" for a reason. "Overrated" is not an acceptable substitute. Post something instead.
Didn't he do that "Little Suzie" song?
Pi Ran Out
You're not alone. It's amazing how the man who is largely responsible for the use of AC power in our society, (Edison tried to champion DC because AC with all it's complex maths was too difficult to understand!), and the radio, (Marconi basically just used Tesla's insights to deliver a viable product for the war effort in WWI), goes unheralded.
There's a reason for this. Tesla worked in such a way which would have exposed the world to ways of thinking about reality which lead to freedom. --Despite his push for exactly the kind of power distribution system described in this article, such thinking would have eventually led to an understanding that all matter, (including elements of the human nervous system), resonates at specific frequencies. This would have led people to question things like cell phones a little more carefully before accepting them.
I've looked and looked, but I cannot find the reference I originally read many years ago now. . . His discovery of the radio was sparked by an incident where he was instantly aware that his mother who was in another country at the time, had just experienced a severe trauma. This experience is what caused him to think along the lines of sympathetic resonance. The science book people of today don't like guys who talk about such things. Again, it's about withholding freeing knowledge from the populace so that they are more easily controlled.
-FL
Whoever modded this insightful obviously wears magnetic immortality rings.
sudo killall humans
Thats why I try not to move around too much, go out in the sun, or wear pants.
Any one of those could heat up my cells a little bit and give me cancer!
Ummm... he actually made one... and caused an earthquake...
http://www.intuitor.com/resonance/tesla.html
The problem with hiding technology is the telephone/radio/programming issue, where more than one person can come to the same conclusion, albeit via different means/functions/devices.
A computer once beat me at chess, but it was no match for me at kick boxing. Emo Philips
And what makes this not waste energy by pumping it in all directions, or not waste energy when there's nothing around to charge?
The antenna is composed of more than a dipole - like a quadrupole or more. (Details aren't clear from the article.)
At large distances the fields cancel out. So energy is not radiated away. At short distances it doesn't cancel out exactly. There another antenna can couple to the transmitting antenna and absorb energy from it.
It's much like total internal reflection with light trying to make it from inside a high-index-of-refraction material to its lower-index surroundings. If the incident angle is increased beyond the angle where the light would be refracted to be parallel to the boundary surface, there's no direction in which the light wave could add up to non-zero strength. Thus the light can't escape. Since the surface isn't "lossy" and can't absorb the energy, the light is totally reflected. But the fields from the light extend a small distance - like a half-wave or so - from the surface (and cancel out rapidly beyond that). If you bring another piece of high-index material close enough to (or touching) the surface, this field will penetrate it. Now the fields add up in a particular direction and the light can travel beyond the formerly totally-reflecting interface. (That's how you measure the refractive index of opaque things like ketchup, and how some fingerprint readers get a clean image.)
Most of our insights about light and radio have to do with the "far field" - where the observer is so far from the transmitting antenna that the angle between lines-of-sight to its various parts is negligible. In the direction of antenna nulls there is no field, because the total of the field from all the points on the antenna adds to zero. But get close enough that the angles become significant and the distances - and thus the wave phases - no longer add up the same way. Then you're in the "near field", where the signal doesn't cancel out.
With this device, as with total internal reflection, you've got an "antenna null" in every direction. There's a significant amount of electric and magnetic field for a quarter-to-half-wavelength from the antenna, but beyond that the field falls off to essentially zero very quickly. Cancelation means the open space acts like a perfect mirror and puts all the energy back into the transmitting antenna before it gets to far-field distances. So there's no load on the transmitter. (The antenna acts like a short or open circuit on the end of the transmission line and bounces all the energy back into the transmitter.)
But bring a probe close enough to the transmitting antenna that the lines between the probe and the transmitting antenna's parts are no longer near-parallel. Then the differences between the distances to the various transmitting parts deviate from the relationship they had at the large distances. You're "in the near-field" and the signal DOESN'T cancel out. The probe can suck in some of the power, potentially with near-perfect efficiency. The loss of this energy may also disrupt the far-field cancelation a little bit, allowing another part of the energy to leak away. But the leaking energy won't exceed the amount captured, since it consists of the fields that would otherwise have been canceling the energy that was grabbed. And other parts of the receiving antenna - which are at other distances from the transmitting elements so things add up differently - can capture some or all of THAT energy. So the leakage may be very small to non-existent. In that case essentially all the energy lost from the transmitting antenna ends up in the receiving antenna's feedline. The transmitter sees the receiver's load (plus the load of any leakage from imperfect field disruption) and the energy is tranferred with negligible loss.
Does this make any sense yet?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way