[atrain] sent in this interesting wireless light bulb. It’s more of a wireless powered LED inside a lightbulb, but you get the idea. A RF signal is recieved by a coil inside the bulb – the AC signal is rectified and used by LEDs to create the light. All the technical details you need to build your own are here.
I thought this was going to be that MIT wireless electricity thing that everyone is raving about lately (like it’s a new idea or something). Glad to see that I was mistaken. Same concept really (nothing new as it states), but very cool to see it working.
Posted at 11:59 pm on Jun 8th, 2007 by Blind Tree Frog
Oh the pranking possibilities with this light. “oh that, that was here when I moved in… don’t touch it though, the ghosts don’t like that”
bwa ha ha ha ha!!!
Posted at 12:41 am on Jun 9th, 2007 by Digital
i fucked around with semaler setup i called it the electro magnetic glow but i used a 24v pcu powersupply red led copper coils but i did use an avr but using a very high powered mosfet and a car battery for the lev and i was able to get a 4″ lev
(but this was a weekend project so i scraped it now)
sorry about my typing i was up all last night preparing for the exams
Posted at 1:40 am on Jun 9th, 2007 by Alex
Hmm, strange domain name “.st” – all I get is a generic link farm type page, no levitation there…
Anyone feeling like setting up a mirror?
Posted at 6:47 am on Jun 9th, 2007 by hannes
Now if i could only translate this to layman’s terms I would be all over this one
Posted at 7:08 am on Jun 9th, 2007 by dirtsnake
>> #4
“Now if i could only translate this to layman’s terms I would be all over this one”
The floating is just magnets pushing against each other.
Basically this is the deal with the wireless electricity. Know the thing about how a good opera singer can shatter a crystal wine glass? Or that bridge that shock itself apart becuase the wind was blowing just right (really cool video). That works because everything has a natural frequency that is defined by it’s shape and composition and all of that (Tesla’s Earthquake machine exploited this. They designe bridges to avoid this these days).
This is exploited with antenna’s. An antenna is designed to be a certain length so that certain frequencies resonate well with it (1/2 the wavelegnth being that magic number as I recall). So if you have a transmitter that is running a AC signal at a high frequency with an antenna that will transmit it you can have an antenna on the receiving side that will recieve that signal and resonate causing a current to flow through it. Effectively you are making a air core transformer that works really really well at a select AC frequency and specfic enviromental conditions.
Posted at 4:39 pm on Jun 9th, 2007 by Blind Tree Frog
I like others though this was going to be the other thing that everyone is jumping up and down about,(funny no one did that eons ago when it was first demonstrated) wonder why everyone is so excited, this prinicpal has been used for years and years, it’s what make all RF devices work
Posted at 8:51 pm on Jun 9th, 2007 by Josh
When I first saw the title of this post, I mistook the article for another. Coincidently, a group out of MIT just published a paper yesterday on wireless power transfer via resonant mutual inductance. The MIT paper gathered significant press (for a scientific paper) and led to over hyping. The group showed that by specially tuning the coils in a typical mutual inductance setup, you can extend the effective rage from less than one coil width to several coil widths. To demonstrate, the MIT group built two large (25 cm) precision tuned coils and used the pair to transmit power from one coil to a lightbulb attached to the other coil.
Wireless power aside, Iâm much more impressed with the magnetic levitation system. I would have assumed the lightbulb power coil would have interfered with any maglev control. Maybe thatâs why it has to float so close to the roof? I think it would have been much more dramatic floating mid-height in the enclosure.
Oh, and incase anyone else stumbles across the MIT hype, donât believe it. The transfer efficiency at 4 coil widths was only 15%, and required precision hand-tuned resonant coils. After reading the paper, there wasnât much room for improvement and any implementation would be expensive and delicate. Personally I donât want to waste 4x the electricity, so that I can charge my cell phone next to the charger, rather than plugging it in.
Posted at 2:57 am on Jun 10th, 2007 by Chuck
that bulb photo seems to be fake…look at the top of the bulb to the solid there’s a shadow…
Posted at 9:06 pm on Jun 10th, 2007 by Terramoto
Wow, someone has replicated what Nicholas Tesla did over 100 years ago…amazing that the most influential scientist in electricty is not only not taught in school but his inventions are now being copied and pawned off as ‘new’. Another one for the non-history books.
Posted at 10:56 am on Jun 11th, 2007 by Jnewman
if you follow the links, the newest version of this sculpture have been put up, much better fabrication and presentation, bulb floating 2.5″ away from top.
very cool. yes, this technology has been around for awhile (which the artist notes), its just a neat visual demonstration that i’d love to have in my living room!
Posted at 10:36 pm on Jun 11th, 2007 by makeitgood
that’s great !
can you tell me what the voltage and current level are in the primary ?
besides, the primary and secondary coils are not the same size… could you tell me more details ?
awesome thing, congrats !
Posted at 3:24 pm on Apr 29th, 2009 by deimian
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Wow, that’s really amazing. I wish I understood more how it worked.. time for google.
Cool hack, I want one of those for my room!
Posted at 11:47 pm on Jun 8th, 2007 by Erik