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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/
I can't see avoiding a large degree of power loss, and the last thing we need right now is something more inefficient than wll-warts.
...
It would also suck to have a random bdy part resonate in a similar frequency
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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Now I know you haven't seen the rats nest behind my desk, but 3 computers (only one a notebook), a PS2, monitor, KVM, Hub, printer, associated power strips, Nintendo DS plug and MP3 player plug... I assure you, I would not just use this for my laptop and MP3 player. I have way too many wires, and if I could remove a dozen or so of them, it'd help a lot. Add wireless networking to the mix, and wireless speakers, and it just might be manageable again... And yes, I know both of those already exist.
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.....
Particularly as TFA clearly says "the team has not built and tested a system".
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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
This amazing new "wire-less" technology is the all the rage to-day.
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.
Nothin new hear really. remember Tesla's dream? Free wireless power. The Huge facility at colorado springs did just that.
The only wireless energy source transmission I've seen so far is with RFID tags. have you ever taken one apart? Chek out the
antennea.. much like the tesla antennea.
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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.
This was concepted by powerman Alex Chiu. You are right. It is not new idea of super energy platform.
I suggest you read Slashdot
...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.
Well, yes, sure, but how can one get through the metal bulkheads with an electromagnetic signal ? Unless your aircraft is made from some type of material that will allow e and b fields to buzz right through it (and if so, perhaps we can sell that material to various Stealth programs, no ?), you're going to have to cut holes for waveguides instead of cable ways.
The major savings in transmitted power in an aerospace environment would be in weight of wiring. If your transmitter / receiver assembly and waveguide pipes weigh less than the equivalent direct copper power busses, then it's all worth while.
Of course, the most likely savings these days has to do with signal / information cables. Replacing complex multi-wire signal cables with digital network / fiber optic busses is your best chance to cut weight.
Other interesting features of a waveform power transmission solution would need to include power interruption devices, load sensing devices, and the like. If this takes off, I would find some millimeter wave radar companies that want to get in on the 'ground' floor.
More like it was (and remains) highly inefficient and would have used a large part of the spectrum. You could have wireless power to your home but you can kiss the cell phone, tv, radio, etc goodbye.
A great deal of Tesla's achievements are apocryphal. There is no real proof about claims of wireless power to motors miles away and other things people attribute to him. In reality he was a clever guy but not this victim of forward thinking/backwards government as his myth protrays him as.
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
Has no one else heard of similar technology from SplashPower http://www.splashpower.com/. I think MIT should check out the Cambridge spinoff before they go any further.
Sorry, this is rubbish. Batteries are generally highly efficient. The efficiency of the system is determined by the charger which can be anything from crap (30%) to excellent (90%).
Deleted
The article mentions resonant frequencies, and I'm suddenly reminded of a certain visor-wearing Starfleet officer always blaming the phase-inducers for some damn thing to do with resonant frequencies...
A-Bomb
I admit, the idea of using this on lower power devices is sexy. Never charging a cellphone, iPod, laptop, or wireless game controller would be great. I just don't know if I would trust it for heavy duty power needs like appliances and computers. What would the rate of charge on something like this be, btw?
However, I hope they can get a version of this working for electric cars. That would be perfect. A transmitter in the garage at home, a transmitter in the parking structure at work, etc... If they could prove it was safe enough, they might even be able to put them near major freeways. (at least at gas stations/rest stops) Never having to plug the car in would be a big selling point for manufacturers.
You would need to make this pretty idiot-proof, however. What happens if someone accidentally steps on a transmitter? Would that alter it's frequency? What kind of problems would that cause? Furthermore, according to the article, both the transmitter and the receiver need to be at the same frequency for this to work. Does that mean this would be a powered antenna? That seems to me like it would sort of negate the point because you would still need some way to get power into the device if it runs completely dry.
This also opens up some other problems, the largest of which I can think of is theft. There would have to be one or two set frequencies these devices could operate on, so someone else is bound to have a matching receiver. If you are doing this in your home in the suburbs, that's fine, but in a crowded metropolitan area, it would be easy for lots of people to siphon power off your transmitter as well. Even for low-power devices like cellphones, that can add up to a lot of cost over time, the only solution being limiting the range of the device, which defeats the whole point of wireless charging.
What Tesla came up with is not alien-abduction fiction, but true.
Unlike what Tesla thought about the aether, we now know what RF energy is, how it propagates, and how it stores energy. We have a decent command over a large portion of the spectrum under visible light (400 nm and lower), and we understand that the frequency is linked to the relative energy of the RF.
I once created a 20.5 MHz version of this using a car battery, but since there's soo much energy, filtering is almost pointless. I ended up wiping out a nice 4 MHz chunk of spectrum and had the FCC on me. To put it bluntly, this stuff is worse than spark-gap xmitters. I ended up dismantling this contraption when I received my Ticket (amateur radio license)
Lest to say, it IS possible, but stick with very very low power stuff over short distances. Otherwise you'll end up doing bad things to your local electronics and receiving gear.
KC9JEF.
Isn't that one of the laws of thermodynamics? Not all the energy would be reabsorbed, correct? And that excess, no matter how small ... well, it would be enough for lawyers if not doctors.
Infuriate left and right
Finally, a solution to Boston traffic!
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!
Me being someone that's been electrocuted more times than I can count, you have to understand why this scares the living shit out of me.
Perhaps you have received electric shocks more than once, but you can only be electrocuted (killed by an electric shock) once.
The real danger here is excessive heating of living bodies, and possible RF burns if your hand gets too near the power transmitter. At 6 MHz, it's too high a frequency for the nervous system to respond, thus it won't shock you, but it still can hurt you.
Tag lost or not installed.
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
You can buy "Wireless extension cords" from ThinkGeek.com
And no, I haven't RTFA.
Yes, I saw that episode. I also saw that using a VERY small weight (like 5lbs max) they made the entire steel bridge oscillate. I believe Tesla did not specify how long it would take, only that it would do so. So IMO the theory was sound. If run long enough the oscillations should induce metal fatigue causing the bridge to fail. Too bad they don't have a bridge they could try to destroy, I'd like to see them hook up progressively larger weights to see if they could take it down.
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This unfortunately seems to be a case of "cargo cult science". It looks like science, but isn't. I just got hold of the actual paper on arXiv.org, and some comments after quickly browsing through are:
1) It is a purely theoretical study made by a physicist, who evidently has little experience within RF engineering. With such a "simple" concept, why didn't he bother making a quick experiment? (Spoiler warning: Many beatiful theories have been killed at infancy by experiments...)
2) He is assuming totally unrealistic Q-values.
3) He doesn't explain how he will get the RF energy into and out of the resonators. The Q-value of these circuits would load his resonators.
4) He is using ridiculous precision in his results (6 significant digits...)
5) Magnetic coupling between tuned circuits has been known for ages, but then of course cast in its standard EE terminology. Now a physicist has rediscovered it...
6) "Publication by press release". Making exaggerated claims in the media is no substitute for peer review (where the peers are within the correct field).
Here's the actual paper the article is about.
Seems to me to be little more than a clever way to couple oscillators using higher order moments (that confine the majority of the energy around the device to be very close as they drop off much faster than inverse squared). The paper contains some interesting preturbation methods for determining how badly other objects in the nearby area would affect such a system, however I haven't had time to go through the math in detail.
Disclaimer: IANAP (but I do have a degree in physics) - any actual physicists like to comment on the mechanism here?
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?
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