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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 need multiple transmitters tracking and beaming sound to the exact location of each device. And the transmitters are going to have to be very close by, and then there are all the obstacles between your pocket and the transmitter that will block the beam. You might as well just use an inductive charger. But still, just like solar freaking roadways and perpetual motion machines we want to believe and since most people don't understand the science these ridiculous and impossible ideas draw people in again and again.

There's a more in depth analysis of why this won't work here: http://www.eevblog.com/2014/08/07/ubeam-ultrasonic-wireless-...


Well, in principle you can divide one transmitter's attention to several devices over time. (Either by changing the direction of the antenna, or more sophisticatedly via beamforming.)

Otherwise I agree with you. Even the tone of this article is unconvincing. I wonder what Andreessen’s due diligence team was thinking, maybe the patents have value?


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 densities are almost certainly physically dangerous to more than ears c) sound doesn't propagate well in air at those frequencies; you're basically heating up air d) transducers are not good at turning sound into 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 approximation for focused lasers. Our intuition doesn't support this because our hearing tops out at frequencies still low enough to do some significant bending around obstacles (though at the higher end if you pay attention you can tell they don't do it as well), so we don't have an intuition of sound acting like a beam, but it can.

There's more to sound than "basic physics", and what you learn in Physics 101 about sound is simplified to the point of total uselessness as in real-life you will never encounter a situation where the prerequisites are met for inverse square falloff.

Mind you, I'm still pretty skeptical, but not about the ability to beam sound. That's established engineering, not wild-eyed craziness.


"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?


OK, since conversation has moved on, let me be blunt: You don't know what you're talking about. Your physics 101 education is not the end-all, be-all of physics, and what "point" transmission does doesn't matter because we aren't talking about points. You are in no position to be lecturing people about physics; you are in a position to be lectured to about physics.


With electromagnetism the energy fall off depends on the radius and the wavelength. If the wavelength is is greater than a certain amount of the radius (the Fraunhofer distance) then the energy fall off is a linear 1/r. This is called the near field.

http://en.wikipedia.org/wiki/Near_and_far_field


Sound which you can't hear isn't going to be dangerous to the ears in a conventional sense. Of course at electrically significant power levels, it is just potentially dangerous generally.


Inaudible sounds can indeed affect and possibly damage hearing. Here's a source: http://news.sciencemag.org/biology/2014/09/sounds-you-cant-h...

Ultrasound can also cause tissue damage at high intensity.

I'd be cautious about making claims that humans are not damaged by high intensity sound, even if inaudible.

Perhaps this is what you mean by saying "a conventional sense" but I just thought I'd expand on your answer in case others read it and get the wrong idea.


Here are the published patents thus far:

http://patents.justia.com/inventor/marc-berte http://patents.justia.com/inventor/matthew-angle

The problem I can see is that the filing date for those patents is far later than public demonstrations such as the one at D9 on or around 04/22/2012


>The problem I can see is that the filing date for those patents is far later than public demonstrations such as the one at D9 on or around 04/22/2012

That would indeed cause a problem in a country with an "absolute novelty" requirement in patent applications, but the United States is not a such a country. In the US, the inventor has 12 months after the first public demonstration to file for a patent, and in this case, the patent was filed within 12 months.



> I wonder what Andreessen’s due diligence team was thinking, maybe the patents have value?

The job of a VC is to sell to later investors. Long term viabilty isn't always in their best interest. I could name half a dozen specifics but I'll let you imagine instead.


a16z can make stupid investments, but usually they don't. my guess here is there is more to this than just simple quackery.


(from the article) >Did the physics actually work? Check

I apologize if this question is terribly ignorant, but do investors publicly disclose the results of due diligence that would lead them to believe in the functionality and practicality of such a product? I'm very interested in learning their opinions on the challenges presented by the naysayers (with whom I agree right now).

I appreciate everyone who provided sources that prove uBeam has, at the very least, some huge challenges to overcome in practicality. Like you mention, though, I imagine that these investors have probably considered these challenges.


As far as I know the circulation of DD reports is extremely limited, usually to the company paying for the report and occasionally the management of the company that was looked at.

In the case of outright BS it stays with the VC, if there are useful 'to-fix' prior to closing items then they usually get passed (sometimes edited or excerpted) to the company.

A general public disclosure is a possibility but I've never seen one, investors are not 'speaking for the company' in any way and if investors started to release such sensitive documents that would be considered a false step by the company (and probably rightly so, the information gathered during the process is company confidential and no VC in their right mind would want to suggest to future investments that they have a cavalier attitude towards such information, be it positive or negative, disclosure should be up to the officers of the company).


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 won't say anything more about to protect his privacy) Meredith is actually genius-level and a relentless work horse. I'd bet big on this one.

If I could work for any one company it would be uBeam. I just started a great position, and I'd do it despite the press. The moment they made an offer I'd be on a plane.

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


> 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.


Tell me what part of the physics you find impossible.


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.


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


Initial patents rarely resemble final technology. There's something you get out right away. Most startups do this.


Given that the patent followed a prototype, it has to in some way resemble the final tech.

The fact remains that Ultrasound is not an efficient mode of energy transmission [1]. Wireless induction is almost certainly more efficient over the same distances. And ultrasound is a potential nuisance and hazard to wildlife and pets in way EM broadcasts simply aren't.

[1] http://dx.doi.org/10.1109/IECON.2011.6119486


Does anyone know how you actually use this? I built the project and ran it then enabled Bluetooth on my Mac and iPhone somewhat expecting to receive a notification of the iBeacon but got nothing. Does it have to be coupled with an iOS app to work or can it send notifications even without an app installed?

EDIT: Figured it out - You need an iOS app as well. There's one that can locate and display iBeacon info here: https://itunes.apple.com/us/app/locate-for-ibeacon/id7387090...

I'm a little disappointed. The use case I had in mind was: Customer walks into a store with iBeacons and is given a notification that they tap which installs the app. I suppose this would have too much potential for abuse though.


Yes you have to couple it with an app. You can use the https://itunes.apple.com/us/app/locate-for-ibeacon/id7387090... app. Just make sure you have the same UUID you gave to the mac app in your list of registered UUIDs on the iPhone.


Well the notification is for the app. So I think it is not intuitive for the app to notify the customer to install itself. Did you understand what I am trying to explain?


One big hole in this theory is that its been widely reported [1] that a transponder was switched off before the pilots last radio contact. The pilots would have had no reason to pull the breakers before the last communication if they weren't already aware of a fire.

[1] http://www.nytimes.com/2014/03/17/world/asia/malaysia-airlin...


Another massive hole is that the closest airport ,at the point where communication was lost, was Sultan Mahmud in Kuala Terengganu. Long runway, approach directly from sea, can accommodate a 747 according to Wikipedia. There is no justification to go to Langkawi which is on the other side of the Malay Peninsula.


Never underestimate "pilot familiarity." In an emergency, a pilot is going to favor an airstrip he/she is familiar with over an unknown one. Perhaps the captain was more familiar with Langkawi?


apparently the co-pilot was fresh off his 777 training which occurred on Langkawi.


It's quite possible to think of reasons why they decided on that course of action. I'm no expert, but here's some based on previous incidents:

They wanted to burn off fuel.

There was a fault with the rudder

There was a fault with the control system

They pilots were dead, and the autopilot was doing something off.


In an emergency, the safest way to burn fuel is to reach the closest airport and then circle it. Not head to a more distant airport which you might not reach because of the very emergency.

All hypotheses will invalidate the major premise: that the pilots chose that particular heading not randomly, but in a calculated attempt to reach the nearest airport because of an emergency. Basically, no matter where the plane would have turned, if you draw a long enough line you will find an airport. But that does not explain anything.


In a dire emergency, you would just dump the fuel and not try to burn it off.


Except, the 777 does not have fuel dumping.

It was not required for certification because it meets the minimum required climb rate with an engine failure after takeoff at Max Gross Weight.


Yes it does:

http://cdn-www.airliners.net/aviation-photos/photos/7/4/7/23...

Look at the top center, at the "Fuel Jettison" switches. (This is a 777-200 non ER, but I doubt the ER model would remove this feature.)


Or even land heavy.



Damage from an electrical fire on board could possibly explain the first transponder going out, even if the crew wasn't aware of the fire yet.


You'd imagine that the transponder going out would immediately bring up a fault warning in the cockpit, though, even if the fire itself had somehow not been detected. But I suppose a sufficiently bad bug in the flight systems might be invoked to cover that.


If so, they would probably already have seen other faults as well, and at the very least have a warning about the transponder being disabled. Their last communication made no mention of any problems.


So, is there a publically traded company that makes fireproof transponders? Because I have this hunch...


there was also rumor captain grow up around that airport. i suggest research his childhood schools if possible.


Also interesting is the amount of damage being done to the wheels as it drives around up there. Some good pictures of that here[1]. Apparently the wheels are designed to leave a mark so they can keep track of the rovers location by looking at the tracks[2]. The tracks spell out JPL in morse code.

[1] http://news.discovery.com/space/martian-wear-and-tear-curios...

[2] http://www.planetary.org/blogs/emily-lakdawalla/2013/1002210...


Thanks for the links, I figured that the lack of compliance in the "tire" section of the wheels would be an issue but that is a bit more damage than I would expect. I am guessing that under some driving conditions you might get up to 50% of the rover weight on a wheel and if that was while the wheel was rolling over a rock, the tendency would be to cut into the aluminium. So one wonders why not titanium outer rims? or a compliance system that would allow the wheel to deform until enough weight had been distributed across enough surface area to keep it under the 'minimal damage' threshold.


Considering the hole is non-structural and it's more than halfway through the original planned mission duration, those wheels look fine to me!

I wouldn't mind seeing the progression, though, since they say it's accelerated recently on the rough terrain.


"It appears to be correlated with driving over rougher terrain."

Who'd have thought....


When I read the article that also popped out for me.

Unbelievably obvious. Obviously somethings are different in the Martian environment, but the laws of physics didn't just look the other way when they saw the rover coming.


Absolutely agree, free software has so much to offer and yet here we see it being promoted using the most desperate and ineffective means possible: dressing up in costumes and handing out flyers to people - people who quite likely just had a positive buying experience at an Apple store which offered real products and solutions and not some half thought out nonsense on a piece of paper that only a few geeks are likely to understand.

They need to find another way, because this isn't going to win over anyone, and it may lead some to believe that free software folk are desperate nutcases (which couldn't be further from the truth). There is just no thought or substance to this campaign at all.


Alright, but how do you explain the instructor who had 3,200 hours on the 777 who was sitting beside the pilot not making any mention of a too low airspeed or incorrect landing configuration right up until it was to late? Makes me wonder if there was some ambiguity in the instrument display or procedures for neither pilot to make mention of any problems.


The pilot expressed his concerns about performing a visual approach to his instructor before the flight. The instructor let him fly anyway instead of instantaneously grounding him and saying, "WTF? This is Piloting 101, go get your shit together."

The instructor let this person fly when he was lacking such a basic skill, and that the instructor came from the same system that allowed this incompetent pilot to attain command of a large airliner. This to me indicates that the system is broken and there's no reason to think it couldn't produce an instructor who was also completely useless at performing a visual approach.


Thanks. Really glad you're enjoying it. The code is a real mess, but I'm hoping to gradually improve it now it's open source.


This is amazing. The UI is absolutely gorgeous. A few minor things I noticed:

-Scrolling seems very laggy when scrolling with the mouse wheel, although dragging with the scrollbar seems fine. This only seems to be happening in the Popular (Now), view. This is under 10.9.

-When I favorite songs, they don't show up in the favorite section although they did after relaunching the app.

-It would be nice if when you moused over a song in the list if it scrolled the full song name into view - at the moment they get cut off and you can't see the full name.

-The song list scrollbar on the right is obscured by the controller at the bottom. I like what you've done with having the songs scroll underneath the slightly transparent controller but the scrollbar should really end where the controller starts.

-I don't seem to be getting notifications from the app even though it's listed in the Notifications app list under the Notifications section of System Preferences.


> Scrolling seems very laggy when scrolling with the mouse wheel, although dragging with the scrollbar seems fine. This only seems to be happening in the Popular (Now), view. This is under 10.9.

OK, we'll check it out.

> When I favorite songs, they don't show up in the favorite section although they did after relaunching the app.

The app doesn't auto-update favorites yet. For now you can manually update via pull-to-refresh.

> It would be nice if when you moused over a song in the list if it scrolled the full song name into view - at the moment they get cut off and you can't see the full name.

Agreed, we're working on this one.

> The song list scrollbar on the right is obscured by the controller at the bottom. I like what you've done with having the songs scroll underneath the slightly transparent controller but the scrollbar should really end where the controller starts.

Good point, i'll have to look into that.

> I don't seem to be getting notifications from the app even though it's listed in the Notifications app list under the Notifications section of System Preferences.

If the app is out of focus you should get a notification popup. We don't store notifications in notification center though, since it doesn't seem useful to keep a history.

Thanks for the feedback. Hit us up @plugformac if you want to get in contact with us in the future.


> The app doesn't auto-update favorites yet. For now you can manually update via pull-to-refresh.

Just to let you know: I favorited a song (using menu bar) and then pulled to refresh in my favorites view. The song was shown twice on the list. Same after another refreshes. After restarting the app the song is shown only once, but after pulling to refresh it's doubled again. The second copy appears slightly after the first, so it's probably some list populating launched twice.

The app is awesome and I loved it at the first sight. Thank you! I didn't know Hype Machine before, but they seem to serve some good music.

You should provide links to iTunes & Amazon to allow easy purchases if someone would like to add songs to their music library.


I haven't seen this before. If you can, shoot us a screenshot @plugformac or support@plugformac.com.

If you click the share button and go to the hypem.com page for a track they have the option to buy the track. We'll have to look into it as well.


You're welcome :) I'd love to see some other platforms supported as well.


Yep, it's for messaging using Dropbox shared folders.


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