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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

#81

Post by dllthomas »

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..…

A good skeptic should always want to be proven wrong, it's just that doing so should be a high standard.

Re: An Inventor Wants One Less Wire to Worry About

#82

Post by foobarqux »

zacharycohn wrote: post #22
doctorpangloss wrote: post #18

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 f…

Lady Gaga's manager is very active in the startup/tech community and is a known angel investor.

Any hits?

Re: An Inventor Wants One Less Wire to Worry About

#83

Post by diydsp »

marshray wrote: post #78

Shouldn't it be "One Fewer Wire"? I'm not trying to troll with pedantry here, I'm genuinely interested in the reasoning that surely went on at the NYT.

lol, irony: http://afterdeadline.blogs.nytimes.com/2011/03/01/fewer-vs-l...

(BTW, since you were one of us who was reading carefully, how did you like this phrase: "it was almost like a stoner’s aha:" ?)

Re: An Inventor Wants One Less Wire to Worry About

#84

Post by marshray »

diydsp wrote: post #83
marshray wrote: post #78

Shouldn't it be "One Fewer Wire"? I'm not trying to troll with pedantry here, I'm genuinely interested in the reasoning that surely went on at the NYT.

lol, irony: http://afterdeadline.blogs.nytimes.com/2011/03/01/fewer-vs-l... (BTW, since you were one of us who was reading carefully, how did you like this phrase: "it was almost like a stoner’s aha:" ?)

Honestly, I couldn't read the second page of that article because I felt too badly about forming an impression of the (surely brilliant) Ms. Perry from it.

The stoner quote was immortal, but I'll raise you:

Nothing in her training prepared her for this kind of research. She was an astrobiologist, after all.

Re: An Inventor Wants One Less Wire to Worry About

#85

Post by mturmon »

gibybo wrote: post #37
Kurtz79 wrote: post #36

Earlier quoted context omitted.

Yes, the radio solution is what I read about in the past. The amount of power needed would really depend on the device and the application, I guess. How many mW are we talking about, in the best case scenario ?

I found some napkin math on stackexchange: http://electronics.stackexchange.com/questions/4664/stealing... One of the answers has the following math: For a large radio tower (100kW), you'd get roughly 80 W per square meter of receiving antenna area at 100m distance. Since the typical distance to a nearby radio tower is probably more like 5 miles, we can reduce that to ~12mW for a 1m^2 antenna. For the size of a phone…

It just occurred to me that the / (4 pi r^2) factor may not be relevant here. The reason is that the acoustic wave could be steered (http://en.wikipedia.org/wiki/Beam_steering) so it does not propagate evenly over all the solid angle.

Perhaps the steering could be done cooperatively with the device(s) being charged. I.e., devices announce their location to the charger, and the charger steers the beam towards them.

Maybe that would bring the power required down to a reasonable range.

Re: An Inventor Wants One Less Wire to Worry About

#86

Post by marshray »

eCa wrote: post #65
vacri wrote: post #50

Earlier quoted context omitted.

I've always found it odd that people talking about sexism use 'woman' like it's an adjective. Common use has made it one, but it used to be just a noun. Anyway, my point is that we don't say "man founders" or "man drivers" or "men professionals".

Me too. I've always thought male/female is a better fit (English not being my first language).

Women sometimes find 'female' offensive. I'm not sure I can fully explain the reason, but it has to do with its use as a biological term.

Re: An Inventor Wants One Less Wire to Worry About

#87

Post by marshray »

etrautmann wrote: post #68
svantana wrote: post #23

I wonder about the health aspect of this. It seems there is very little known about long-term exposure to high intensity ultrasound. Also, there could be a risk of ear damage if a non-linear material came into the sound field, and producing distortion artifacts in the audible frequency range - given that about 1W/m^2 can be enough to cause damage.

It can't actually harm your hearing, by definition. Hearing damage caused by high intensity sound is the result of mechanical transduction of sound waves to hair cells in your inner ear. When the amplitude of a certain frequency is too high, the cells responsible for turning those mechanical vibrations into electrical signals are physically damaged. Ultrasound is mechanically filtered, so it can't propagate into your…

No filter has an infinitely steep cutoff slope, it's a question of the 'degree' of attenuation. It may or may not be safe in practice, but if it is it's not "by definition".

50KHz is just two octaves above our normal range of hearing. She's claiming "charge laptop in 3.5 hours" levels of power transferred to a transducer "the size of a flash drive" a useful distance away.

Now apply the inverse square law to estimate the necessary output power or assume a focused beam.

Now imagine that flash drive is your ear, your eyeballs, or a pregnant lady.

Re: An Inventor Wants One Less Wire to Worry About

#89

Post by nekopa »

greenyoda wrote: post #42
tedsanders wrote: post #34

Earlier quoted context omitted.

Even if you had a working prototype, there's no way people will buy it until you can solve reliability, yield, cost, etc. A prototype that took 100 tries to make and cost $1000 and works only for a minute under the right conditions will never find a buyer. It's not enough to transmit wireless power - you need to transmit wireless power cheaply, reliably, safely, durably, etc.

Especially when what you're competing with is a conventional power supply that costs less than $10 to make, is small enough to carry in your luggage and can be used wherever there's an electrical outlet. (The device in the article is going to require an unobstructed path between the charger and the device to be charged, so it won't work very well in a place like a coffee shop where there are lots of bodies and furnit…

Unless they mount them on the ceiling...

Re: An Inventor Wants One Less Wire to Worry About

#90

Post by espeed »

"Each expert seemed to dwell in his own private silo, so that whenever she crossed from one discipline to another, she would run into the same wall of constricted thinking."

Keeping abreast of emerging tech is hard for specialists whom are focused deep within their silos. It's always good for teams to include broad-minded generalists that continually survey the landscape, connect the dots, and keep the team's reservoir stocked with fresh developments from the outside world. At some point a specialist may recall something from the reservoir that turns out to be the missing piece that enables your team to break through the silos and jump the curve.

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