Scientific Grandstanding at MIT

witricity at MIT.

Am I missing something here? It's a transformer. This is how my wife sonicare charges.

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Kiteman10 years ago
The difference is the range - toothbrush chargers are almost in contact, witricity works at a range of >2m. I don't get all the details, but it's not a strict magnetic link. The witricity "resonates" - the power-transfer starts small, and each cycle of the signal pushes the power up in the receiver a little more (like small pushes on a swing), until it's enough to do something useful. As I understand it, the plan is to create a system that charges mobile devices (laptops, phones, mp3 players) just by having them in the right room, not connected to the mains via a knitted mess of cables and chargers.
Kiteman Kiteman10 years ago
Oh, and if a normal transformer was operated over that range, it would have to have a strong enough field to drag cutlery across the room.
Whee! Fork shooter!
Tool Using Animal (author)  Kiteman10 years ago
So it's a resonant LC circuit? Like a Tesla coil? BTW The actual range cited in the abstract is 8r, so that 2 m range requires a 1/2m dia. coil.

It's the too cutesy name that makes it suspect.
"The experimental setup consisted of two 60cm (2ft) diameter copper coils, a transmitter attached to a power source and a receiver placed 2m (7ft) away and attached to a light bulb."

http://news.bbc.co.uk/1/hi/technology/6725955.stm
endolith8 years ago
I'd like to see you transmit energy over 2 meters at 45% efficiency with a transformer.