An Inventor Wants One Less Wire to Worry About • Hacker News Board

Re: An Inventor Wants One Less Wire to Worry About

#41

Post by greenyoda » Sun, Aug 18, 2013, 8:25 PM UTC

lreeves wrote: post #38

hkmurakami wrote: post #35

Most of us here are discussing the science of this thing. But let's just say that the science somehow miraculously works. Would any of you actually want to buy that big square thing and put it in your rooms? I can't imagine I would.

If it actually works it'll inevitably be miniaturized over time I'd imagine, pretty much like everything else in technology.

Electronics have gotten miniaturized, but that doesn't mean that a mechanical device that generates sound vibrations can be miniaturized. For example, an iPhone contains the computing power that used to take up a large room, but we don't have loudspeakers that are 0.01 inches in diameter and deliver the same sound output as conventional ones.

Re: An Inventor Wants One Less Wire to Worry About

#42

Post by greenyoda » Sun, Aug 18, 2013, 8:38 PM UTC

tedsanders wrote: post #34

bnegreve wrote: post #17

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.

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 furniture in the way.)

Re: An Inventor Wants One Less Wire to Worry About

#43

Post by nwh » Sun, Aug 18, 2013, 8:43 PM UTC

tocomment wrote: post #28

Here's what I've been wondering. A transformer provides very efficient wireless power transmission but on a few centimeters. Has anyone considered scaling up a transformer? Would that increase the range? What if we made a house sized one and buried it under the house? Could that provide wireless electricity to the whole house?

You'd still be battling the inverse square law. Wireless power is just too inefficient to ever be used for serious appliances.

Re: An Inventor Wants One Less Wire to Worry About

#44

Post by leoedin » Sun, Aug 18, 2013, 8:49 PM UTC

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…

I think the equation given does give units in watts/m^2? Unless I'm missing something, power has the units of W, and the only dimensions on the bottom of the equation are the radius, which is meters. Because it's r^2, the result is in W/m^2.

For a non-directional beam, it would be P/(4.pi.r^2).

Re: An Inventor Wants One Less Wire to Worry About

#45

Post by gibybo » Sun, Aug 18, 2013, 8:58 PM UTC

leoedin wrote: post #44

gibybo wrote: post #37

Earlier quoted context omitted.

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…

I think the equation given does give units in watts/m^2? Unless I'm missing something, power has the units of W, and the only dimensions on the bottom of the equation are the radius, which is meters. Because it's r^2, the result is in W/m^2. For a non-directional beam, it would be P/(4.pi.r^2).

Yea my mistake, I missed the units on the radius :( thanks!

Re: An Inventor Wants One Less Wire to Worry About

#46

Post by mattdeboard » Sun, Aug 18, 2013, 9:12 PM UTC

ferongr wrote: post #4

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

What if we came up with a way to directly connect the device to the ubeam device? Like some kind of connecting wire through which the energy could travel? THEN we'd have some serious efficiency!

Re: An Inventor Wants One Less Wire to Worry About

#47

Post by kiba » Sun, Aug 18, 2013, 9:22 PM UTC

zerohp wrote: post #29

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..…

I think that the reason this new idea came from someone outside of Physics or Electrical Engineering is because its poor efficiency is obvious to people with a background in those fields. Sometimes it takes an outsider to challenge assumptions and achieve a breakthrough, but I don't think thats going to happen in this particular case.

If you have really low power sensors, you could use the technology to power it indefinitely in conjunction with other power generating modules.

Re: An Inventor Wants One Less Wire to Worry About

#48

Post by iyulaev » Sun, Aug 18, 2013, 9:23 PM UTC

Did anyone else read this and immediately wonder, "how many watts?" 1.5 pages of prose and no hard numbers. Years in the industry reading marketing white papers and such cause things like this to really set off the bullshit detector. I'm not saying it's not possible, but, just give me the power (in watts) that is being transmitted by a prototype device. If you don't put that number as a feature bullet, I automatically assume you've got something to hide.

Re: An Inventor Wants One Less Wire to Worry About

#49

Post by cma » Sun, Aug 18, 2013, 9:25 PM UTC

iyulaev wrote: post #48

Did anyone else read this and immediately wonder, "how many watts?" 1.5 pages of prose and no hard numbers. Years in the industry reading marketing white papers and such cause things like this to really set off the bullshit detector. I'm not saying it's not possible, but, just give me the power (in watts) that is being transmitted by a prototype device. If you don't put that number as a feature bullet, I automaticall…

I was wondering about the watts for a different reason...

From Wikipedia:

"Although the long term effects due to ultrasound exposure at diagnostic intensity are still unknown,[24] currently most doctors feel that the benefits to patients outweigh the risks.[25] The ALARA (As Low As Reasonably Achievable) principle has been advocated for an ultrasound examination — that is, keeping the scanning time and power settings as low as possible but consistent with diagnostic imaging — and that by that principle non-medical uses, which by definition are not necessary, are actively discouraged."

Re: An Inventor Wants One Less Wire to Worry About

#50

Post by vacri » Sun, Aug 18, 2013, 9:29 PM UTC

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…

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".