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Audacious Plan to Make Electricity as Easy as WiFi

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Re: Audacious Plan to Make Electricity as Easy as WiFi

#51

Post by s_q_b »

gerbal wrote: post #50
s_q_b wrote: post #47

Earlier quoted context omitted.

Meredith Perry is no fraud. She was in a Penn graduate program before this venture, and has worked at NASA. It's directional transmission technology. The power loss is minimized as the ultrasound is directed and focused at a particular location. There's no inverse square law here, and it's easily within the bound of known physics. As far as I know, (indirect relationship with the a good friend of the founder, that I…

I don't care how smart she is, she can't defy the laws of physics. Also, the reflection and harmonics are going to drive any animals and/or children & teenagers nuts.

She's not defying the laws of physics. It's a tracked directional system that concentrates the ultrasound at the point of the device. Honestly, not even really that out there as far as the physics is concerned.

EDIT: Unlikely. Children hear better in upper ranges, not lower. And animals are unlikely to be too perturbed. These types of noises are generated naturally all the time.

The challenge here is the engineering. How precisely can you build the tracking? How much leakage is there? Are there problems with harmonics? How do you build an app that can relatively reliably 3d position a device relative to a base station. And finally, how do you get that base station to be able to simultaneously or rapidly re-aim itself to target each of the devices. That's hard, but certainly exciting and very possible.

Re: Audacious Plan to Make Electricity as Easy as WiFi

#52

Post by chillingeffect »

Tesla drove himself crazy trying to transmit power wirelessly.

Physics and nature make it hard to safely transfer a large amount of energy between a source and our bodies. Wide beam = loss. Narrow beam = destroying human flesh.

Wireless anything has a reality distortion field around it.

This plan seems like it is bulging with "almosts."

I don't think it will go widespread, but it will be a valuable niche. Kind of like google glass and segways. Their job is to find that niche. Perhaps in a laboratory or food processing factory setting? or another manufacturing environment where a machine or robot must operate wirelessly.

Re: Audacious Plan to Make Electricity as Easy as WiFi

#53

Post by seasoup »

Wow, I didn't expect this level of skepticism and negativity on hacker news. This is exactly the kind of audacious, potentially world changing invention that hackers should be striving for. Merideth has my respect. We should be supporting her in this endeavor, not trying to tear her down.

Re: Audacious Plan to Make Electricity as Easy as WiFi

#54

Post by gerbal »

s_q_b wrote: post #51
gerbal wrote: post #50

Earlier quoted context omitted.

I don't care how smart she is, she can't defy the laws of physics. Also, the reflection and harmonics are going to drive any animals and/or children & teenagers nuts.

She's not defying the laws of physics. It's a tracked directional system that concentrates the ultrasound at the point of the device. Honestly, not even really that out there as far as the physics is concerned. EDIT: Unlikely. Children hear better in upper ranges, not lower. And animals are unlikely to be too perturbed. These types of noises are generated naturally all the time. The challenge here is the engineering.…

The patent application[1] lists the transmission frequency as 40-60kHz, a high frequency. Humans typically hear up to around 20kHz, dogs 44kHz, cats 79kHz. Not Low frequencies.

A directed, concentrated, high decibel volume, in the 40-60kHz range is not the sort of thing found naturally 'all of the time.' As other posters have mentioned, transmitting energy via sound is likely impossible do both safely and at useful amperage. Ultrasound is not safe at high energies even if you can't hear it.

[1] patentimages.storage.googleapis.com/pdfs/US20120299541.pdf

Re: Audacious Plan to Make Electricity as Easy as WiFi

#55

Post by gerbal »

seasoup wrote: post #53

Wow, I didn't expect this level of skepticism and negativity on hacker news. This is exactly the kind of audacious, potentially world changing invention that hackers should be striving for. Merideth has my respect. We should be supporting her in this endeavor, not trying to tear her down.

For selling Snake Oil to foolish investors?

Re: Audacious Plan to Make Electricity as Easy as WiFi

#56

Post by kybernetyk »

s_q_b wrote: post #47
johnw wrote: post #11

There's noway that this is going to be practical within the current laws of physics. You can't use a wide beam to cover an area because the amount of energy available drops by orders of magnitude the further you get from the transmitter. If you used a focussed beam (which is what they are suggesting) then you need a separate beam that tracks and follows the location of each device. So to cover a very small area you'd…

Meredith Perry is no fraud. She was in a Penn graduate program before this venture, and has worked at NASA. It's directional transmission technology. The power loss is minimized as the ultrasound is directed and focused at a particular location. There's no inverse square law here, and it's easily within the bound of known physics. As far as I know, (indirect relationship with the a good friend of the founder, that I…

> This is a "First they dismiss you. Then they laugh at you. Then you win" scenario.

Then god knocks at your door and angrily asks why you didn't obey the laws of physics.

Re: Audacious Plan to Make Electricity as Easy as WiFi

#57

Post by kybernetyk »

seasoup wrote: post #53

Wow, I didn't expect this level of skepticism and negativity on hacker news. This is exactly the kind of audacious, potentially world changing invention that hackers should be striving for. Merideth has my respect. We should be supporting her in this endeavor, not trying to tear her down.

> We should be supporting her in this endeavor, not trying to tear her down.

Yup. Also we should write nice letters to the guy currently working on perpetual motion ... (for which patents have been filed too btw).

Re: Audacious Plan to Make Electricity as Easy as WiFi

#58

Post by xkcd-sucks »

pocketstar wrote: post #14

I am skeptical of the claimed safety of uBeam. The FDA does not advocate the safety of ultrasound. From the article: "Was it safe? Well … for starters it is just an inaudible soundwave being transferred – as in the kind also used for women during pregnancy." From the FDA: "Even though there are no known risks of ultrasound imaging, it can produce effects on the body. When ultrasound enters the body, it heats the tiss…

I use "inaudible soundwaves" on a daily basis to turn cells into formless goo. It's so destructive that we generally only use it for really tough things like bacteria.

Ultrasound is also really good at chopping up DNA into little fragments.

Granted, this is for 10s-100s of watts, but I still avoid putting my fingers into the low power sonic bath... cargo-cult superstition dies hard.

Re: Audacious Plan to Make Electricity as Easy as WiFi

#59

Post by seasoup »

seasoup wrote: post #53

Wow, I didn't expect this level of skepticism and negativity on hacker news. This is exactly the kind of audacious, potentially world changing invention that hackers should be striving for. Merideth has my respect. We should be supporting her in this endeavor, not trying to tear her down.

And when it's working, against everything you said, what will you do then? I hope you'll at least admit you were wrong.

Re: Audacious Plan to Make Electricity as Easy as WiFi

#60

Post by scottlocklin »

jerf wrote: post #46
scottlocklin wrote: post #27

Earlier quoted context omitted.

If I were a VC invested in this, I'd want hearing tests on the engineers working on this project; once a month, over time. Of course, if I were a VC, I wouldn't invest in this, because it is physically retarded on inspection. Whoever did the dil on this is either a fool who doesn't understand basic physics, or was bribed somehow. Off the top of my head a) sound energy falls off as 1/r^2, b) that those sorts of energy…

"a) sound energy falls off as 1/r^2" No, it doesn't. That's how it falls off when being transmitted perfectly spherically in an environment that won't reflect or refract anything. Consequently, this turns out to be a not-very-useful equation in practice. In particular ultrasound can be beamed just like light, making the "perfectly spherical transmission" not even a close approximation, just as it is not a good approx…

"In particular ultrasound can be beamed just like light, making the "perfectly spherical transmission" not even a close approximation"

You do realize that energy from a point source of light also falls off like 1/r^2, right?

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