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An Inventor Wants One Less Wire to Worry About

nytimes.com

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Re: An Inventor Wants One Less Wire to Worry About

#11

Post by sxp »

A demo at All Things D 2 years ago: http://allthingsd.com/20110602/demo-at-d9-ubeam/

The design in that video involves transmitting ultrasound from a central charging station to an ultrasound receiver and that receiver is then plugged into a cell phone using a normal cable. The claim in that video is that it takes 3.3 hours to charge the receiver but she doesn't actually mention the watts or joules involved. Given that most claims of technology that can charge a device from across the room have turned out to be bullshit, I'm going to lump this claim of into the same bucket until there is more evidence to show otherwise.

Re: An Inventor Wants One Less Wire to Worry About

#12

Post by marshray »

keithpeter wrote: post #7
ferongr wrote: post #4

How can one extract usable amounts of power out of sound? Even 100dB SPL has actual power around 1mW/m2.

Concentrated beam I imagine. I wonder about heat generation locally.

It's a laptop charger ... and a crowd control device!

Re: An Inventor Wants One Less Wire to Worry About

#13

Post by etrautmann »

I'd be curious to see a graph of transmission efficiency vs. distance. The technology here is almost certainly acoustic beamforming, and that large square under wraps in the image is an array of small ultrasonic piezo speakers. Beamforming will give you better than 1/R^2 relationship between power and distance, but probably nowhere close to linear.

I'd be hard pressed to imagine this working over distances larger than the 3 feet demonstrated, which suggests constraints on the use case, like charging your laptop while its on a desk, for which there would seem to be easier methods of wireless charging (inductive coupling, conductive pads, etc).

Very interesting in concept, I'd like to see numbers before I believe anything.

Re: An Inventor Wants One Less Wire to Worry About

#14

Post by JoshTriplett »

ferongr wrote: post #9
keithpeter wrote: post #7

Earlier quoted context omitted.

Concentrated beam I imagine. I wonder about heat generation locally.

It's more likely that a somehow extremely directional soundwave would knock a phone off the table than provide any appreciable amount of power.

The ability to create a directional soundwave powerful enough to move specific objects from across the room would be a highly useful invention of its own, quite aside from remote power charging.

Re: An Inventor Wants One Less Wire to Worry About

#15

Post by javajosh »

At first I felt awful because I was thinking like part of the establishment: there's no way she came up with something that will replace power cords. I've got a degree in physics, and have always been interested in acoustics, and sound in air has some amazing properties, including the ability to transfer non-trivial amounts of power, especially at nodes, and especially when focused with, say, a parabolic reflector.. The best case would be a tracking parabola that follows your device through space beaming concentrated ultrasound at it, and even then the power transfer is going to be a handful of milliwatts. The power draw of modern laptops is around 10 watts (although it varies somewhat). This, of course, is the bet case ignoring inefficiency to transfer that mechanical energy back into electricity (piezo is probably really efficient, but coupling the sound to the piezo won't be).

I was feeling really bad about myself, but then I realized: without such skepticism the surprise and delight of proving others wrong (not to mention being proved wrong) would be lessened, and so my skepticism does serve a useful purpose, and I could go on living with myself again. This is one skeptic who's hoping that he's wrong and that the inventor is right!

Re: An Inventor Wants One Less Wire to Worry About

#17

Post by bnegreve »

It’s one thing to pull an idea out of your head and shape it into a prototype. But it’s a whole other thing to figure out how that device will get out of your test kitchen and into the marketplace.

Hum... in this particular case, the problem is to make a prototype. If you have a working prototype for safe wireless energy transmission, no doubts that you'll find customers willing to buy it.

Re: An Inventor Wants One Less Wire to Worry About

#18

Post by doctorpangloss »

Did she have a hard time finding investors because it was a hardware business, or because she was a woman?

Did she ultimately get investment because she was a woman, in spite of the hardware business?

According to a friend's college thesis, there are lots of concrete reasons VCs don't invest in women.[0] In summary, VCs don't take a girl very seriously. The thesis makes the case though that there's real opportunity for women founders, not the least because they're so undervalued for reasons under than business fundamentals.

So maybe Meredith got investment precisely because she was a woman. The collection of investors is curious. According to CrunchBase, Marissa Mayer invested in 8 companies over the last 2 years (+Square in 2009), 7 of which have women founders or co-founders. Lady Gaga's manager, who I thought was not a professional investor, in fact makes a lot of investments. According to CrunchBase, 4 of 16 of his investments have women founders or co-founders. By comparison, VentureSource shows about 1 in 14 startups with funding have women founders or co-founders in 2010—more details in Alisha's paper.

Still, it would be wrong to accuse of sexism the "hundreds" of the investors who declined her project. She's an astrobiologist who wants to run a mass-manufacturing business. I'm not a venture capitalist, but I can see aversion to hardware manufacturing risk generally being the biggest factor here.

[0] http://alisharamos.com/women-vc-funding/AlishaRamos_Thesis.p...

Re: An Inventor Wants One Less Wire to Worry About

#20

Post by Kurtz79 »

javajosh wrote: post #15

At first I felt awful because I was thinking like part of the establishment: there's no way she came up with something that will replace power cords. I've got a degree in physics, and have always been interested in acoustics, and sound in air has some amazing properties, including the ability to transfer non-trivial amounts of power, especially at nodes, and especially when focused with, say, a parabolic reflector..…

Funny, I was thinking that most people with an engineering/physics background would dismiss the though that spurred her to investigate the matter in the first place ("why in this day and age should I plug my "wireless" device to charge it") as just absurd, and drop the issue without a second thought...

Wireless power is something that has been researched for years I believe, the fact that to this day there is not a feasible solution (that I know of) means that it's a really hard problem, I guess.

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