Slashdot Mirror
A Tablecloth to Charge Your Laptop
moscowde writes "Research scientists at the University of Tokyo have come up with a unique sheet-like material that can transmit electrical energy over a large area to nearby devices without the need for direct contact, so it can be made into a tablecloth or wallpaper and your appliance can be anywhere on a surface to get charged.
The system uses organic molecules as transistors, microelectromechanical switches, and miniature copper coils to transmit energy using electromagnetic induction."
i think we're talking about a dupe.
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If this could help get rid of the mess of power plugs and cables under my desk, this would be utterly fantastic. Wonder what happens if a liquid is spilled on the surface though...
I'm sure there's nothing harful in wrapping ourselves in yet more electromagnetic fields, not even shielded ones in this case.
I mean, what could possibly go wrong? After all little Jimmy's third arm is quite handy.
Nothing I want more than putting my metal cup down on a frayed kink on the basement table with my bare feet. Wearing a pacemaker?
Sweet, no cords for my laptop! but i still need to plug in my dinner table. personaly if i wasnt at a work station id be in a chair with my notebook on my lap
It sounds cool and convenient, and unlike the RF couplers that have cropped up lately they are up-front about efficiency: >80%, which they achieve by activating only the area where the power "receiver" sits--not blanketing a large area. However, the energy-conservation targets set by EPA, California, etc. are even higher. There needs to be further improvements before this can be a marketable solution. I hope they happen soon!
My soup has electrocuted a fly!
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
These endless stories of prototype devices that transmit electricity wirelessly are really not very interesting at all, especially after the tenth story on them. Let's just forget about them until they can actually be bought and reviewed. Jeez.
It sounds like magnetic induction -- same thing they use to charge electric toothbrushes without exposing any wiring to water and toothpaste. It should work just fine with water.
My questions on this would be more focused on how practical it'll actually be, unless it's standardised so that different devices can charge off it, and on how wasteful it is, if it's throwing out energy even when nothing needs it.
http://hardware.slashdot.org/article.pl?sid=07/04/ 30/1630217
One of the intriguing Nichlai (sp?) Tesla did in his lab was to place an inductive ring just below the cieling like crown molding. Then he had electric motors powered by inductive coupling. Instead of "plugging" in the device to the wall socket, all he has to do was to raise a ring the ceiling. To "unplug", lower the ring by a few inches. Will try to find some references and post it soon.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Nope, you just have simpler needs than others. I have a laptop and desktop on a LAN, firewire external drives, usb printers, joypads, headsets, phone, camera, etc., and I'd still consider that a very modest setup. My plan for a rack-like setup is very much held back right now by cable planning. Not that it's insurmountable, of course.
Some of these types of EM sources really bother me. At certain frequencies I can actually feel the EM field as a slight tingling in my skin. My Wacom tablet does it but my hand has to be pretty close to it to feel anything (which is really annoying because I otherwise love that tablet).
I wonder what this would feel like? I imagine it would have a pretty high level of output, I wonder what frequency it runs at and if it will bother some people. It could make being anywhere near one of these charging table cloths pretty uncomfortable.
The ratio of people to cake is too big
I see a lot of sparks when i use wool blankets and a acrylic t-shirt, maybe thats what started this project?
http://hardware.slashdot.org/article.pl?sid=07/04/ 30/1630217
Article references to University of Tokyo and organic molecules as well.
1. What are the power losses like?
2. Will it give me brain cancer?
http://en.wikipedia.org/wiki/Inductance
They're using their grammar skills there.
Is no one worried that the cloth will block the air vents in the bottom of the laptop case, causing it to overheat?
I cannot find any reference, however I recall reading an article several years ago which detailed a consumer deskpad which contained dozens of micro contacts. The idea was you simply lay your laptop, mobile phone, pda on the pad, and it begins to charge. Of course this product assumed that your devices were outfitted to use the charger. A microcontroller would actively sense the current between pad contacts, allowing charging, but preventing short circuits. Again, as I cannot locate this product now, I expect it did not take off.
Inductive charging also seems inefficient to me. The article claims 80% efficiency. What exactly do they mean? How many AC-DC conversions take place within this charger?
Also, my laptops require more like 80w. It may be okay for PDAs and mobile phones.
IMO, a good research project, but not yet near a consumer product.
In original research paper published in "Nature Materials" there is a picture of a fish tank with fish inside. The light inside the tank is powered using this transmitting material. Power cables, sockets, and plugs are not required, and all of the metallic parts are coated with insulating materials. So it is safe.
Lord Armstrong, a Victorian inventor and armaments manufacturer had one of, if not the first, electrically lit house in the work. Cragside" was lit (initially by carbon arc lamps but then by Joseph Swan's incandescent light bulbs) powered by hydroelectric power. During the day horses pumped water to a lake up the hill side. During the night that water generated electricity.
The table lamps replicated old oil lamps in style but had spikes which poked in to table clothes which were threaded with copper wire carrying current. This meant you could carry them around, put them down, and they would just light.
So if I wear gingham trousers I can use my laptop on my lap without having to plug it in? Fantastic.
Induction - doesn't this mean your hair will stand on end whenever you're holding cutlery? Or is the field too weak/short-ranged for humans to notice?
Thats what i like about slashdot a lot (versus digg) :)
(almost) no dupes.
Hivemind harvest in progress..
The first great add-on I see to this is the ability to crank up the current and voltage so that all the people at the conference table are shocked into paying attention. Too many people brings their Notebook PC's to meetings, and then they glue themselves to the screens. Answering instant messages, typing notes, playing games, who knows what! And they all clamor for the plug because they all seem to be low on power...
With this, they can be 'charging' and also 'shocked' when needed...
I saw a TV Program about something Phillips developed a few years ago, for the kitchen of the future. They showed a table cloth that you could put electric candles, heated plates, and even a food tester on.
There's nothing wrong with anything - Phillip J. Fry
How efficient is it? In these days of global warming the last thing we should be thinking is replacing all those chargers which are left plugged in 24/7 with something that's even less efficient...
No sig today...
Just get a wool tablecloth, a dozen hamsters running in circles with cables in their mounths and you'll get the same effect.
I'd be willing to try this out with my laptop. Aero on my Vista eats the battery so if this'll give me power without cords..woo hoo!
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Induction is nothing new. Submersible waterpumps use inductive impellers. Every chemistry lab I've ever been in has used both inductive mixers and inductive heaters. This is all established, stable technology.
Even inductive charging is nothing new - I've had a toothbrush that does this for years.
So when I read articles about inductive mats saving me from my rat's nest of cables, don't think I'm not enthusiastic about the prospect. My concern, though, which I haven't yet seen addressed adequately, is what sort of an effect this kind of inductive magnetic field is going to have on my sensitive electronics and their magnetic storage. I have to say that I'm a lot more than merely hesitant to lay my laptop down on such a device. Everything in me says - no, screams - "You're throwing your hard drive to the wolves!"
I'm not thinking such a mat is throwing off gauss like a bulk eraser, but it doesn't have to. It might not wipe a drive clean in a single sitting, but I can't imagine that prolonged exposure is not doing minute, cumulative, and ultimately fatal, damage to the drive. Or am I missing something?
"Hey, the third matrix movie would have been good except for the plot,story, and acting." --AC
There's a company commercializing a similar concept called splashpower. I don't work for them, although I have worked with them. It's really cool technology and, suprisingly enough, it's not vaporware.
Hopefully they'll actually have their modules out for public use sometime soon...
I don't see this so much as an 'electric tablecloth' concept rather an inlay for pressboard style tables (large conference room tables come to mind)..if these are manufactured to a standard spec, then all that needs to be done for each individual device is a receptor to take that power source and convert it into the voltage/ampereage necessary for that device. Another neat use for it would be a mousepad for your wireless mouse to keep it charged all the time..just imagine, being able to game with a wireless mouse and not have to worry about batteries..
I remember a science teacher in the early 1980s telling us of an incident from a farm.
Then I found it as a Physics exam question.
A farmer reportedly stole electrical power by strategically placing a large coil of wire beneath the high-voltage transmission lines that crossed his field. For several years, the farmer obtained free electricity to operate equipment for his farm, until the power company finally discovered the theft. Eventually the farmer was convicted of stealing power even though no physical connections were made to the transmission lines.
Maybe it was ripped from the headlines, CSI style. Or maybe it's just an apocryphal tale. What impresses me is the fact that I was a 12 year-old in England when I learned this, and this example comes from a University test in the US. It might say something about why America has lost position to European countries in technology...
Women's stilletto heels are made with steel spikes.
Have you ever been in a ground-floor office where the electric power was run over the concrete floor below the carpet, without trenching the concrete? And if you've worked in an office like this you know that women's high heels tend to drive that steel spike down into the material and cause an explosive short across the damp concrete.
Best not use your electric table cloth in the wrong kind of establishment. Spill a beer, go to jail!
--- I am known for the ones who want to find me on the net. Is that a privacy risk or a privilege? One might wonder..
Magnetic fields fall of as the CUBE of the distance, so don't expect this tablecloth to be all that useful. It will probably require no more than a centimeter between the sending and receiving coils, possible less. Also note that any uncaptured power ends up being dissipated in the sending coil, so it will make a nice heating pad for your sore muscles. If you don't mind a magnetic field going into you as lagniappe.
damn right... i hope everyone understands they don't read Digg either!
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wouldn't it be great if you had a small stand that you could mount on the wall or put on your desk, where you would put your cell phone, pda, and other gadgets? Between me and my wife we have 2 phones, two pda's, game boy ds, wireless mice, mp3 player etc.. and all the matching (and different) wall warts to charge them.
How about also building in the ability to communicate when on the pad? That way your pda or cell phone could automaticaly sync when on the pad. How about mouse pads that charge the mouse?
How about a coffee mug that heats up when on the pad?
The possibilities are endless!
No more power plugs going bad from mechanical wear (the cause of death of most of my cell phones)..
If this could be scaled up to higher voltage/amperage you could replace wall sockets with these.. totaly safe for the kids. You could probably make small little adapters for old plugs. (yes you'd have to have some kind of locking mechanism since walls are vertical, maybe magnetic like apple power plugs?)
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You may recall the cochlear implant (developed here in Australia, I did a B. Med. Sc. on further research with the team who did it). They've been implanted for decades and are kept charged wirelessly by induction from a power supply coil held in place by a magnet. It's all pretty darn close to the brain, unsurprisingly. There's reams of biological safety data on it, though the devil may be in the details if this system is substantially different.
Lloyd