uBeam Ultrasonic Wireless Charging – A Familiar Fish Smell - Page 1
Forum section: electronics / projects

author: EEVblog
author_rank: Unknown
timestamp: August 07, 2014, 02:36:45 pm
content: Not really crowd funding, so I've put this one here:http://www.eevblog.com/2014/08/07/ubeam-ultrasonic-wireless-charging-a-familiar-fish-smell/

author: Lightages
author_rank: Unknown
timestamp: August 07, 2014, 02:56:55 pm
content: You basically got that debunked. Who needs to be so inefficient just so you can pretend to have convenience. I would guess a charging efficiency of like 10%. Some countries have banned the sales of incandescent light bulbs because they eat too much energy. Actually the stupid thing is that incandescent bulbs are 100% efficient in the winter when they also contribute to the warming of the house, and they are also nearly 100% recyclable without hazardous wastes being involved. Sometimes good ideas should just stay that, an idea. Wireless charging using sound waves is as stupid as the solar roadway idiocy.

author: German_EE
author_rank: Super Contributor
timestamp: August 07, 2014, 03:52:39 pm
content: Dave, why not have a 'Fundamentals Friday' covering the Inverse Square Law on the whiteboard and then demonstrating it in action? You need not even use RF energy, a light bulb and your light meter will probably suffice.And thank you for the reminder to charge my mobile phone

author: chicken
author_rank: Frequent Contributor
timestamp: August 07, 2014, 04:39:02 pm
content: That rectangular antenna is probably a "phased array"http://www.olympus-ims.com/en/ndt-tutorials/phased-array/Also could explain the highly secure communication they "stumbled upon". In theory if focus is perfect, only the targeted device can hear the communication.Still leaves the problem of how to support multiple devices. Maybe the antenna contains dozens/hundreds of transducers that can be grouped to generate individual beams for several receivers at once.

author: chicken
author_rank: Frequent Contributor
timestamp: August 07, 2014, 04:45:46 pm
content: Yup, phased array it is, from the 20120300592 patent:Quote

author: Unknown
author_rank: Unknown
timestamp: August 07, 2014, 04:51:14 pm
content: Oh man!It's bad enough that we have to live with RF spewing all over the place in a typical cityfrom an infinite number of wireless devices.Now we want our phones to be charged with ultrasound from a distance,despite various barriers, and incidental reflectors. You'd have to soakthe area with a lot of watts even when the energy is focused on a user.The shit will be bouncing all over the place.I'd like to see how many watts of ultrasound it would take to transmitenough energy to charge one phone in a reasonable amount of time, in a cafe space.Not to mention the unknown health effects on people exposed to such intense ultrasound.I think the project is about patent trolls creating patents, betting on the future use of ultrasoundthat comes anywhere close to power or information transmission.Just get up off of your fat(or boney) ass and plug in your phone'sadapter, sit back down, and lap up your overpriced coffee.

author: chicken
author_rank: Frequent Contributor
timestamp: August 07, 2014, 04:59:42 pm
content: Re health, from Wikipedia:QuoteExplains their "up to 155dB" limit.

author: Precipice
author_rank: Frequent Contributor
timestamp: August 07, 2014, 05:17:35 pm
content: I look forward to the appalling audible howl as these sources of continuous high power ultrasound beat against each other.I wish I was shameless enough to scam like this.

author: electronic_eel
author_rank: Regular Contributor
timestamp: August 07, 2014, 06:30:10 pm
content: poor little bats - won't be coming anywhere near the city if this were real.

author: German_EE
author_rank: Super Contributor
timestamp: August 07, 2014, 08:09:31 pm
content: The local dog population might object as well

author: amyk
author_rank: Super Contributor
timestamp: August 07, 2014, 08:44:15 pm
content: If these start to become commonplace they might be more functional as insect/bat/etc. repellers than power sources...

author: eneuro
author_rank: Super Contributor
timestamp: August 07, 2014, 08:53:34 pm
content: Hopefully, localhttp://www.greenpeace.org/members will not allow those devices to be used in public placesFree energy is there in thunder storms and lightingEach spot on this map is a lot of lost lighting strike energy.All you need is LF RF antena to receive this energy and power "something" eg. crystal radioIt is much closser to reuse storms energy to Tesla Tower than those stupid uBeam'shttp://en.wikipedia.org/wiki/Wardenclyffe_TowerApparatus for transmitting electrical energy.Inventor: Nikola Teslahttp://www.google.com/patents/US1119732BTW: We have about 4 months to take this big idea back into the life and celebrate its 100th anniversary while it was patented to Nikola Tesla at december 1914-12-01

author: free_electron
author_rank: Super Contributor
timestamp: August 07, 2014, 10:53:46 pm
content: Quote from: EEVblog on August 07, 2014, 02:36:45 pmthe bats will shit like crazy ... when they fly through the beam ...

author: EEVblog
author_rank: Unknown
timestamp: August 07, 2014, 11:13:16 pm
content: A "power meter"And, well, this speaks volumes:

author: EEVblog
author_rank: Unknown
timestamp: August 08, 2014, 12:47:11 am
content: Quote from: 3roomlab on August 08, 2014, 12:27:35 amThe good thing about it is that it's a very closely coupled resonate system, so not a huge amount of energy escapes. When no device is on there to charge the power drops to almost nothing.But ultrasonics is a fundamentally different concept, it is power at a distance. Get in the way of that beam and well, I hope you've done adequate research...

author: coppice
author_rank: Super Contributor
timestamp: August 08, 2014, 02:19:12 am
content: Quote from: chicken on August 07, 2014, 04:59:42 pm120dB causes hearing loss, but it takes 155dB to harm the human body. Isn't deafness harm?

author: coppice
author_rank: Super Contributor
timestamp: August 08, 2014, 02:20:15 am
content: I can't figure out if she's a scam artist, or a classic display of the Dunning-Kruger effect. When she talks about the "power meter" in the video she speaks with the confidence of someone who doesn't even realise they are bullshitting.Its easy to transfer substantial amounts of energy wirelessly, using several forms of carrier energy, provided you don't care about efficiency or collateral damage. Bring those two into the picture and everything changes. :-) Her quick Google to see if someone had done anything like she is proposing should have trawled up a lot of hits. We don't see too many of those in production use today. I wonder why? :-)To be fair, she does address the focussing issue that Dave implied she skipped over. The video does say the charger and chargee need to be paired, and the acoustic beam needs to constantly steered, with the chargee constantly feeding back to the charger to control that steering. No indication is given of how a suitably tight beam might be formed, though. The patent applications all seem content free.

author: othello
author_rank: Contributor
timestamp: August 08, 2014, 02:20:22 am
content: @Dave / All,I was wondering, i remember reading a long time ago about Nikola Tesla and the projects he was involved in. This subject made me think of Tesla again, was his idea viable to provide wireless energy at long distances, what is your opinion ? Sorry for the newbie question if i'm opening now a can of worms

author: djacobow
author_rank: Super Contributor
timestamp: August 08, 2014, 02:20:43 am
content: Quote from: EEVblog on August 07, 2014, 11:13:16 pmUmm, that second video... wow.I have a hard time believing she was talking to experts and getting wildly different answers. Much more likely is that she was asking wildly different questions.Will it work? That depends heavily on what "it" and "work" mean. If "it" is a reasonably-priced product that not too complex and "work" means some modicum of end-to-end efficiency and not blasting people with 150dB+ of ultrasonic energy, yeah, no, it's not going to work. But I can think of other definitions of "it" and "work" for which this may be possible.But the video is pretty astounding in terms of the sheer disregard for expertise and for engineers in particular. I guess that's what it takes to be a visionary. Maybe most visionaries are monkeys pounding on typewriters. Every once in awhile one types out of a few sentences of Shakespeare, then thinks it /is/ Shakespeare.In honor of that Ted Talk, I give you the matching Onion Talk:

author: coppice
author_rank: Super Contributor
timestamp: August 08, 2014, 03:19:07 am
content: Quote from: djacobow on August 08, 2014, 02:20:43 amThat Onion video is excellent.She probably did ask the same question of a number of experts. Its a common effect. Ask a few experts if something will work, and....Some will answer the science question "could this be conceptually demonstrated with no regard for other factors?"Some will answer the engineering question "could this be made and deployed as a practical engineered product, causing little or no collateral damage?".Its a matter of whether the expert thinks in a more sciency or more engineeringy way.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 08, 2014, 03:39:35 am
content: Quote from: 3roomlab on August 08, 2014, 12:27:35 amOne dot is somewhere out in the orbit of Mercury!

author: calin
author_rank: Regular Contributor
timestamp: August 08, 2014, 04:18:59 am
content: Well .. I really think she truly believes is a discovery; and for her it is 100%. The ted talk title .. "how to become a technology innovator without an engineering degree" ... says it all. The answer is you will be "AN INNOVATOR" in your empty balloon that is supposed to host a brain. Typical case of knowing so little that you don't even realize you don't know anything and you think you are an scientist; perfect test subject for this type of presentation.Unfortunately this is a disease that we start seeing more and more all over the place. I mean peoples that so uninformed and naive on a subject that they truly think are experts on the subject and everyone before them in that domain was fundamentally wrong. Remembers me of something that my grandpa used to say "Well ... everyone is an expert at agriculture and football .. problems start when you plant something that grows too big and you have to dribble around it."

author: EEVblog
author_rank: Unknown
timestamp: August 08, 2014, 04:34:25 am
content: Quote from: coppice on August 08, 2014, 02:20:15 amYep, I found all those links to research and articles on my first page of Google results, I think most of them pre-date this project by a long way.QuoteAnd therein lies the rub. As usual with projects like this there is no real proper engineering demo (after what 4 years and a million or two invested?). Just seems to be the odd mention from some tech writers or journalists who claim to have seen some sort of demo. Most likely those people would be fooled by the "5V output" nonsense too.If I had this thing even remotely feasible I'd be making a dozen videos screaming to the world and investors - "Look, see, it really does work, it really is promising, look at the efficiency and tracking we are getting etc etc.But no, after 4 years all we seem to get is a photo in the New York Times of, well, something?Meah

author: Precipice
author_rank: Frequent Contributor
timestamp: August 08, 2014, 09:18:46 am
content: Quote from: coppice on August 08, 2014, 03:19:07 amIt's always hard to know how to answer those questions.If you go for 'Yes, BUT', the asker's brain shuts down in a cloud of $$$$ and glory after the first word.If you go for "No", you're just being negative.Perhaps the answer, when faced with a well funded and charismatic loon, is to say "I can try to make it work. I'm good at that sort of thing, give me cash, not shares"And then buy a lot of really good earplugs, ear defenders and hope your bones don't shake apart...

author: eneuro
author_rank: Super Contributor
timestamp: August 08, 2014, 11:43:23 am
content: Quote from: othello on August 08, 2014, 02:20:22 amLook at those experiments where 100 years ago in Nikola Tesla laboratoryTESLA'S OSCILLATOR AND OTHER INVENTIONS - AN AUTHORITATIVE ACCOUNT OF SOME OF HIS RECENT ELECTRICAL WORK.where in one of them in the room wired around they were able switch the light on without any wires, but a small loop to lampHowever, do not try to do at home this one, whereQuoteQuoteIt must have been very taff time for Tesla's teamThis is about what was in Nikola Tesla mind those daysTHE TRANSMISSION OF ELECTRICAL ENERGY WITHOUT WIRES by Nikola Tesla (March 1904)QuoteThere are many other interesting articles written by Tesla too.It is a big pleasure to read those articles from the past, especially while they display date like thisQuotewhich means Dec 1917, but those days we can feel the same while we can write:Quotebut 100 years laterWhen you see this stupid idea with ultrasound powered devices it looks like uBeam CEO should Google longer than a few hours to invent something realy not useless

author: idpromnut
author_rank: Unknown
timestamp: August 08, 2014, 11:47:37 am
content: Quote from: Precipice on August 08, 2014, 09:18:46 amFunny, I have often found myself at the wrong end of these types of questions (be it kooky ideas or people trying to solve real problems) and I usually never answer yes or no: I usually start off with a question that is designed to make the person think about the original question. If they don't engage I typically extract myself from the conversation/argument ASAP.

author: EEVblog
author_rank: Unknown
timestamp: August 08, 2014, 12:01:04 pm
content: Quote from: Precipice on August 08, 2014, 09:18:46 amThe number of people who commented exactly that on my Solar Roadways video must now rank in the hundreds

author: jeremy
author_rank: Super Contributor
timestamp: August 08, 2014, 12:11:26 pm
content: Quote from: 3roomlab on August 08, 2014, 12:27:35 amThe signals measured by an MRI are more like RF transmission than inductive loop power. But if you mean that people are exposed to a strong magnetic field, then you are correct.However, magnetic dosing is very interesting topic, and one which is still being researched. Although nothing has really been obvious (to my knowledge), some are still interested in learning about magnetic field "dose levels" experienced by machine operators.Also, I've been told that if you get a high field MRI (>=7T), power it up and move around it quickly, you can generate eddy currents in your brain which can cause dizzyness, nausea/vomiting and fainting. So don't let your kids run around while the MRI is on

author: Precipice
author_rank: Frequent Contributor
timestamp: August 08, 2014, 12:12:17 pm
content: Quote from: EEVblog on August 08, 2014, 12:01:04 pmMostly, I just think "fsck'em", and go about my day. It's hellish annoying, watching people shovel cash into these abysses, though. Whether it comes form individual funders or institutions, it's still grim. Then again, it's all part of some huge game, and I shouldn't let it get to me. And that's the point at which I wonder if I'd take their shilling. And their shilling...

author: German_EE
author_rank: Super Contributor
timestamp: August 08, 2014, 06:41:11 pm
content: "Also, I've been told that if you get a high field MRI (>=7T), power it up and move around it quickly, you can generate eddy currents in your brain which can cause dizzyness, nausea/vomiting and fainting. So don't let your kids run around while the MRI is on"There is some quite interesting medical research being carried out on the effects of magnetic fields on the brain. It certainly doesn't cure migraines though, I know this because I was part of the study group.

author: Falk
author_rank: Contributor
timestamp: August 08, 2014, 08:41:45 pm
content: Hello,this looks like the little sister of Steve Jobes. Good presentation, limited engineeringOK, Steve DID push the edge much forward, starting with iMAC (ok, just nice looking), continuing with iphone (the first "real" smartphones) itunes, ipad and so on. He did this by using the latest available technology and having the best designer around.So far so good. He might bend the laws of media distribution (itunes), but not the laws of physics. 10 years before, all this would not have been possible, due to the lack of such highly integrates CPU, TFT LCDs, memory and so on. All the early smart phones, blackberry, newton etc. proof this.OK, back to topic. A lot of wuss around hot air. Haven't we seen this before?http://www.witricity.com/What do they claim?http://www.witricity.com/technology/witricity-faqs/"How does WiTricity's technology differ from traditional magnetic induction?"What products do they have?A demo kit.http://www.witricity.com/products/prodigy/A reference kit for 5W, not betten than normal Qi stuff.http://www.witricity.com/products/wit-5000/3.3kW reference kit. Sounds impessive, but is noting special in the industry. Also 10-20cm gap ist standard.http://www.witricity.com/products/wit-3300/Absolutely NO sign of a power transfer, that is beyond existing technology. No Nicola Tesla revivalBut what do they have in HUGHE amounts?http://www.witricity.com/technology/intellectual-property/PATENTS!This sounds like the rambus business strategy to me

author: SirNick
author_rank: Frequent Contributor
timestamp: August 08, 2014, 09:44:27 pm
content: Quote from: Falk on August 08, 2014, 08:41:45 pmThe major difference between Jobs and a hack like this is Jobs was a (real) visionary grounded in practicality. There's a world of difference between pushing the envelope and spouting sci-fi nonsense.Jobs understood technology enough to know when it had matured to the point it could achieve the goals he was setting for the product, and then brought together vendors and engineers that could realize those goals. While some of that technology existed before, it was either too expensive or too unreliable to be ready for consumers. History is littered with companies falling to either side of that crucial point (by jumping the gun or waiting too long and being late to market.)These people seem to think if you believe hard enough you can change the laws of physics. That's not a visionary, it's just delusional.

author: eneuro
author_rank: Super Contributor
timestamp: August 08, 2014, 10:44:23 pm
content: Quote from: Falk on August 08, 2014, 08:41:45 pmWiTricity Wireless Warfighter ideaIt looks much better than this uBeam, however in this video they  forgot that when they provide wireless electricity to military soldiers than... their enemy can use their energy while it is not possible to encrypt it

author: coppice
author_rank: Super Contributor
timestamp: August 09, 2014, 05:35:52 am
content: Quote from: SirNick on August 08, 2014, 09:44:27 pmIf jobs understood anything, how come he did such a fantastic job of sinking Next? He had the best software platform ever developed, at a time when Windows had not yet established itself. He made a series of greed based decisions and killed it. Next lives on, in a watered down form, as the current Mac OSX platform, but its no thanks to any brilliance on Jobs part.Jobs just got lucky.

author: old gregg
author_rank: Regular Contributor
timestamp: August 09, 2014, 11:22:41 am
content: if this is so obvious imaginary undoable stuff how can she be funded with so much money ? Some people aren't questioning things before investing money at those huge corporation ?or do they go only for the mediatic exposure, marketing crap, and if the product is produced, possible money feedback ?

author: SeanB
author_rank: Super Contributor
timestamp: August 09, 2014, 12:07:18 pm
content: Some could be Astroturfing, but most likely is from those with little understanding of basic physics, and sadly those are likely to be in a majority. If you thought the maths in an art major was hard, and did not do physics in high school as it was either difficult, smelly or required thinking a little then you are likely to believe the charging via sound ( with the inverse cube law and the basic impedance mismatching on both sides being a difficult problem) is doable.Most people do not realise than of the 100W you provide to a speaker 98W ends up as heat in the voice coil, the remaining 1W ends up as heat in the wiring, with 1W being used to heat up the room with sound waves. This is at best efficiency. With a horn you can get about 20W of audio power at a small range of frequencies, where the horn is large enough to do the impedance transformation, but not too large that it acts as a resistance. Do that at both ends and you might get 4W out for 100W in with them facing each other with no clearance between them.

author: Falk
author_rank: Contributor
timestamp: August 09, 2014, 12:57:37 pm
content: Quote from: old gregg on August 09, 2014, 11:22:41 amYou remember the dot com bubble? Same thing, just smaller in scale.One of the biggest dot com insanities in germany were the licences for the upcomming UMTS mobile network. The companies paid 100 billion euro (american billion = 100.000.000.000) For comparison. The whole iridium sattelite network costed just 8 billion, including ALL hardware!

author: Falk
author_rank: Contributor
timestamp: August 09, 2014, 01:05:11 pm
content: My guess, it would me much more efficient to charge your gadgets with solar power, derived from solar cells in your hat, coat, shirtOf use a fuel cell, just order two B52 at the bar, one for you, one for your smart phoneOr put a generator at your rocking chair.I heard bio gas is a growing energy source, just have a mean bean stew an . . .

author: coppice
author_rank: Super Contributor
timestamp: August 10, 2014, 02:26:56 am
content: Quote from: SeanB on August 09, 2014, 12:07:18 pmSmelly? I think you've confused physics with chemistry.

author: SeanB
author_rank: Super Contributor
timestamp: August 10, 2014, 06:52:00 am
content: Physics has a smell when you do experiments wrong, and in any case you typically will have both Physics and chemistry together initially.

author: Yago
author_rank: Frequent Contributor
timestamp: August 10, 2014, 08:41:45 am
content: Quote from: Falk on August 08, 2014, 08:41:45 pmI got something very similar from the videos.I felt that what was really being sold was Meredith Perry, a future as a great motivator, public speaker and supporter of "unorthodox inventors" (tongue firmly in cheek!). Notice Her G W Bush body language and posture, also it appears she has set points in her speech(on the sheet!) with "look at the audience" instructions etc, IE has sought training in public speaking but not electronics!The "invention" could be an attempt to justify her inventor role for the future rather than actual profit.As said, I too still wouldn't be surprised at all if this went mainstream, people are really that slavish to gadgets and fads.Wanna buy the new Nike trainer, WiFi, GPS, 20Mpix cam, and stun gun functionality built in! :p

author: djsb
author_rank: Super Contributor
timestamp: August 10, 2014, 11:41:35 am
content: I'm just waiting for one of my design students to be given something similar to this as a project in my lab. To give them credit the students themselves have more sense and generally listen to what I have to say. We shall see. If I see it mentioned in my lab I'm going to have to upset some people.I'm also wondering why there wasn't a "power meter" on the transmitter half of the setup as well in that video. Maybe they didn't want to encourage people to ask too many questions. I had to laugh as well when I saw the bog standard cheapo ultrasonic transducers used on the prototype. Surely with all that money they could do some reasearch into different transducers as a minimum. But that would mean applying for research money and funding someone.

author: EEVblog
author_rank: Unknown
timestamp: August 10, 2014, 01:38:37 pm
content: Quote from: djsb on August 10, 2014, 11:41:35 amTo be fair, that prototype was before they got any money at all. As I understand it it was lashed together in a few days for a TV demo they got invited to.I think she was just genuinely clueless about the difference between voltage and power in this instance at that early stage.

author: EEVblog
author_rank: Unknown
timestamp: August 10, 2014, 01:42:46 pm
content: Quote from: old gregg on August 09, 2014, 11:22:41 amOften they aren't "huge corporations", they are run on the whim of the founder with the deep pockets. If that person likes the idea, they make it happen.The idea is that you throw money at a hundred crazy ideas, and you only need a one of them to go gangbusters to make a fortune and easily pay for the 99 that failed.

author: miguelvp
author_rank: Super Contributor
timestamp: August 10, 2014, 07:26:09 pm
content: Wasting 90% of the power might be Ok in their minds if it's intended to be used in a place where you pay over $10 for a cup of coffee.It's the cost of convenience

author: eneuro
author_rank: Super Contributor
timestamp: August 10, 2014, 09:17:22 pm
content: Quote from: djsb on August 10, 2014, 11:41:35 amMaybe thisevvblog: Tesla (Tower) Wireless Power Transfercould be worth to try too in labs, while demonstrations showed in"Tesla Wireless Power Transfer"by guy from club in Zagreb confused many participants with much higher than average knowledge of modern physicsDecided to put it to another thread, while maybe someone will knew about software to make simulation like in this presentation using Maxwell's Equations while you might have educational licenses to such sophisticated software?I was able to derive speed of light from those equations using academic math, but this mentioned in this presentation is for the moment above my math skills to try to verify those simulation results and those claims, however experiments made might be possible to try to do in home.Tesla tower was not finished these days in, but destroyed about 100 years ago there might be something to investigate

author: TimNJ
author_rank: Super Contributor
timestamp: August 11, 2014, 02:10:11 am
content: The idea is interesting, but her TED talk really pissed me off. Her arrogance and attitude towards people of greater education (in the area she is working in) and experience is revolting.Lately we've seen a bunch of "great ideas" from these "ingenious innovators" and while you must encourage innovation, many of these innovators really forget about the practical implications of their ideas. It's not that the idea of wireless power transmission is intrinsically bad. Of course not; that would be terrific. But you can't ignore the laws of physics, no matter how much hype you get from the media or how big you dream.And so I can't completely blame her as it seems the media got her on-board the hype train, which is probably partly the reason she thinks her idea is so brilliant. (Gee if the media thinks my idea is awesome, then it must be great!)Mind you I am merely a 19 year old EE student, with only a summer's worth of internship experience, but I still find the TED talk to be very distasteful. Her lack of trust in those who have actual knowledge of the technologies she is experimenting with just proves her arrogance. The engineers she talked to didn't want to shut down her idea because she is a non-engineer, but they knew the practical roadblocks in her way. Why does she speak of engineers and physicists with such negativity? Who created the transistor? The IC? For the most part everything we enjoy and love today is a product of innovators who, YES, weren't afraid to think outside the box, but were also very knowledgeable in the field they were working in.So to put down similar people and accuse them of being robotic, systematic, or linear is just asinine. Want to see real innovators? Step inside an Intel R&D lab. Or go to a Quantenna lab where you'll find a wise graybeard working on the RF front end for the latest 802.11 standard. Or NASA. Or...well you get it! Those are the guys (and girls) doing the real dirty work that makes real progress happen...not this imaginary fluff.I could go on for days...but this attitude is really appalling.

author: corrado33
author_rank: Frequent Contributor
timestamp: August 11, 2014, 04:38:04 am
content: I'm still wondering why there was such a HUGE box on the receiving end of the initial demo. Maybe a bunch of batteries perhaps? I mean, you see circuit boards smaller in a laptop, and this was for a simple power converter?Or they could have simply bought two of the same size, but regardless, it's a very fishy product.The whole ultrasonic idea isn't a great one. Many animals can hear much higher frequencies. Dogs, as the most often quoted example, can hear up to 60kHz, while these transmitters are transmitting at 40kHz.Dear ASPCA, (That's the American Society for the Prevention of Cruelty to Animals for you non Yanks)This girl wants to torture dogs, please help.Concerned Citizen.Yeah, this will never fly.

author: EEVblog
author_rank: Unknown
timestamp: August 11, 2014, 05:27:24 am
content: Quote from: TimNJ on August 11, 2014, 02:10:11 amAnd ironically she has to of course hire those same practical people:http://ubeam.com/careers/I invited her to come here and explain after she complained on twitter:QuoteAnd then when Chris asked if such details would be provided:QuoteSo after 3 years and already $1.7M invested, still no data they can release.Where have I heard this before? Oh yeah, Solar Roadways...

author: EEVblog
author_rank: Unknown
timestamp: August 11, 2014, 05:31:56 am
content: Quote from: corrado33 on August 11, 2014, 04:38:04 amYes, they admitted in the videos and also in the patent drawing there is a battery storage device, a.la the Airnergy device.QuoteI can't see how it possibly can apart from some niche somewhere. It's going to be expensive and complicated even if they can get it working in a reasonable way.Inductive charging pads are here now, built into a lot of phones already, cost under $20, don't need an external dongle on the phone, no battery storage, and are efficient and safe.How can this possible hope to compete?It's almost exactly like solar roadways.

author: EEVblog
author_rank: Unknown
timestamp: August 11, 2014, 05:41:16 am
content: Quote from: miguelvp on August 10, 2014, 07:26:09 pmSo, I'm wondering, because, you know, I have thoughts...how does the coffee shop scenario work anyway?This thingneedsan intelligent receiving dongle, presumably still with battery in it. Does everyone have to own and carry around this dongle?Or do you have to go to the counter and ask for one? What if you buggered off with it?Or if it's on the bench then why not just have an inductive pad or charge cable there and keep it simple.

author: TimNJ
author_rank: Super Contributor
timestamp: August 11, 2014, 05:50:27 am
content: Quote from: EEVblog on August 11, 2014, 05:41:16 amBecause that wouldn't be thinking outside of the box Dave! Silly silly. Thats far too practical and economically feasible anyway.

author: coppice
author_rank: Super Contributor
timestamp: August 11, 2014, 05:52:27 am
content: Quote from: EEVblog on August 11, 2014, 05:41:16 amEven if she can get something to market, she'll be bankrupted by the class action law suit from dog owners.

author: miguelvp
author_rank: Super Contributor
timestamp: August 11, 2014, 06:17:53 am
content: Quote from: EEVblog on August 11, 2014, 05:41:16 amI'm not defending them, but same with witricity or whatever they are called, last I've heard only 15% made it to the receiver. At least that one used electromagnetism by extending the induction range by magnetic resonance.But giving uBeam the benefit of the doubt, It's no different than transmitting from a tunning fork to another. Sure there will be losses but some energy will make it there as long as it's tuned to the resonant frequency.Maybe using two frequencies and the receiver operating at the right harmonic frequency? don't know and don't really care how or if they'll solve it.At the end it's useless since an induction coil as you mention is way more efficient, and it could communicate with your phone so they can charge you for the refill.It doesn't matter anyways since HAARP can transmit 3.6 MW wirelessly so it's been done already.Edit: Also, microwave GigaWatt beams have been used bouncing them off satellites.And I guess Japan is soon to have solar freaking power in Space!!!!4 square kilometer solar panel in orbit transmitting the power with 1-gigawatt microwave back to earth! (in 30 years)

author: coppice
author_rank: Super Contributor
timestamp: August 11, 2014, 10:10:01 am
content: Quote from: miguelvp on August 11, 2014, 06:17:53 amI don't think waste of energy is a big drawback here. They aren't looking to power high power devices, where the waste would run into megawatts. The problem is where that wasted energy goes. Just a watt or two of acoustic energy is very loud. The fact that it is inaudible doesn't mean it won't damage your ears, or drive your dog insane.Quote from: miguelvp on August 11, 2014, 06:17:53 am

author: eneuro
author_rank: Super Contributor
timestamp: August 11, 2014, 12:17:47 pm
content: Quote from: coppice on August 11, 2014, 10:10:01 amHere is something about HAARP project " HOLES IN HEAVEN - SECRET TESLA TECHNOLOGY "but posted by... UFOTVWho knows what kind of experiments really are made using this technology, while public information must be far from reality only to hide what is inside this kind of projects.

author: EEVblog
author_rank: Unknown
timestamp: August 11, 2014, 12:42:22 pm
content: Quote from: coppice on August 11, 2014, 10:10:01 amMobile phones, maybe not. But laptops which they also claim, then yeah, I'd say that's "high power" in the context of this technology at the consumer level in the home and public/work spaces.

author: coppice
author_rank: Super Contributor
timestamp: August 11, 2014, 01:21:57 pm
content: Quote from: EEVblog on August 11, 2014, 12:42:22 pmFair point. A 50W charge of a laptop at 10% efficiency starts to look bad.

author: sunnyhighway
author_rank: Frequent Contributor
timestamp: August 11, 2014, 01:39:21 pm
content: The video shot at the consumer trade show convieniently stops at 2:02, just when she wanted to show off the iPhone actually charging.

author: daqq
author_rank: Super Contributor
timestamp: August 11, 2014, 02:43:04 pm
content: QuoteWith a single device (assuming charging a phone with, say, 2.5W) it's a fair amount of power just lost. With hundreds, tens of thousands of devices world wide it's a LOT of power wasted. Strive for efficiency in your designs.Basically this whole concept can be summed up as a replacement of a proven, well understood, widely available system with near 100% efficiency (cables) by a Rube Goldberg solution with a low efficiency system with tons of potential issues (health, reliability, cost...) that sounds nice on paper for about five seconds, then an engineers mind goesfor the sake of looking cool until everyone gets the same tech... I wasn't particularly fond of wide spread induction charging (lower efficiency, stray magnetic fields etc.) but this wins in WTF by several orders.

author: bfritz
author_rank: Regular Contributor
timestamp: August 12, 2014, 06:38:27 pm
content: I'm going to go out on a limb here, and agree with her, to some extent....Many times in my 30 year career, I have seen engineers say it couldn't be done, simply because their thinking was stuck with certain limitations. I myself have been caught stuck. For years I'd tell people that accurate fuel gauging couldn't be done with only voltage information, and I myself have now proven this wrong, I was highly involved with developing a product used in many mobile devices that gauges based on voltage and how that voltage changes with time.It's easy to look at a demo from someone who admits they don't understand all the details, and poke holes in it. Let's look at a technology that I think is similar and draw some parallels.How many here have seen the demos of Cota by Ossia?Company Website:http://www.ossiainc.com/TechCrunch Video:http://techcrunch.com/2013/09/09/cota-by-ossia-wireless-power/The Cota product uses an array of antennas to performing the aiming to handle the issues with safety. It is possible that uBeam could perform similarly. The real trick is telling when energy is being received by which antennas, and how much is being received, and therefore calculating how much is being lost. When too much is lost, you assume that something else is getting the energy, and look for alternate paths. This is a tricky problem, but not impossible.Just because uBeam is not telling you all the details, does not mean they don't have more to show. Showing too much, too early, can be a problem for a startup. If they have funding that is adequate for the present, disclosing too much publicly, can simply give the competition the information on how they've been stuck in their thinking, and allow them to beat you to market.Yes, I have an Engineering Degree. I worked hard to get it. But I've learned a lot over the years. Those with degrees, don't always have the best ideas. Sometimes, being encumbered with the knowledge of why something won't work, gets in the way of finding the way to make it work!uBeam could be total hogwash, but it is an interesting direction, on something that could radically change the way we use and power devices. I'm not ready to totally denounce it. Given the right talent, this might take off... or the safety and regulatory issues could eat them alive... but you need to take the journey to determine for sure!

author: Richard Crowley
author_rank: Super Contributor
timestamp: August 12, 2014, 06:45:03 pm
content: The efficiency of all air-coupled transducers is desperately horrible compared to the kinds of efficiency required for reasonable power transfer.

author: eneuro
author_rank: Super Contributor
timestamp: August 12, 2014, 08:05:03 pm
content: Quote from: bfritz on August 12, 2014, 06:38:27 pmWhatever it means, Zeine from COTA said:QuoteWhat about 1kW/m2 from the sun every day in space? It looks like PV panels are forgotten technology at those meetingsQuoteDid he showed how much time it will take to charge this device?But forget about all those wireless power transfer prototypes while here it is real free wireless energy device:TPE- TESLA Power by EneuroIt uses free lighting LF 350kHz frequency and receives its energy from hundreds of kilometers/miles !!!It has infinity efficiency while its input power is 0.000000000 W (0 nW)

author: bfritz
author_rank: Regular Contributor
timestamp: August 12, 2014, 08:53:46 pm
content: Quote from: eneuro on August 12, 2014, 08:05:03 pmYes he did. There is a watt being received by the device. So, even with losses, a 5.5Wh battery should easily charge from empty in 8 hours. I've talked with Zeine, and talked with OSSIA regarding the technology... it is not only possible, it is being demonstrated. The real next leap for them is producing a product, that hits the price targets.The idea is that this is in your home, and your device is always charging. Can you imagine how different your home might be, if a lot of the devices that require a wall wart today, were always fully charged, and ready to go? Can you imagine not having to worry about plugging in your alarm clock... or other small power consumers? This is a real change to the way we use things.

author: eneuro
author_rank: Super Contributor
timestamp: August 12, 2014, 09:19:23 pm
content: Quote from: bfritz on August 12, 2014, 08:53:46 pmTesla's idea was free wireless energy, and using small PV solar panel one can charge all his gadgets using wireless energy from the SUN.If someone do not want plug it into the wall socket, can glue small solar cells and light on 100W light bulb-efficiency will be much better than with this hi-tech new age wireless useless technologyQuote from: bfritz on August 12, 2014, 08:53:46 pmI don't have to imagine that while my alarm clock is triggered by rising sun and charges during the day using small old 1inch2 garden solar panel worth 1$ or less at average current 10mAI don't have to even setup its clock while it is synchronized and adjusted by the sun...

author: bfritz
author_rank: Regular Contributor
timestamp: August 12, 2014, 10:58:33 pm
content: eneuro,Yes solar power and PV works for some things, but is not going to be viable for charging a cell phone at a watt, indoors, without wiring to the phone. You can denounce what is being stated here, but you're only showing how you don't get what the value of these devices are. A PV panel generates electricity. Neither of the devices being talked about by me, or the original posting is generating electricity. It is simply providing a transmission method.You are so busy laughing at how "idiotic" the idea is, that you've failed to see, Cota has been demonstrated, and actually works. It is able to transmit power from an array of antennas, determine which have a path to the device, that aren't blocked by losses (a human in the path), and utilize the best path to get the greatest power transfer, while keeping the power transfer to levels that if a human is subjected to them for a small time, is not a problem. (Yes, there are environmental, health and safety regulations on this.)Lots of people laugh at new ideas. There are plenty of famous quotes by technologists who stated why would they ever need more than a certain amount of memory. There are plenty of quotes about what could anyone possibly want a personal computer for? These people lacked vision. This is what you have done, demonstrate a lack of vision.

author: EEVblog
author_rank: Unknown
timestamp: August 12, 2014, 11:03:48 pm
content: Quote from: bfritz on August 12, 2014, 06:38:27 pmNo one says it can't be done. It can be. That's not to point. The point is it's never going to be practical enough when an existing solution exists that is cheap, practical, efficient, low power standby, and already built into many phones.No matter how clever the technical solution, the fact remains that this technology does not add enough value to overcome the inevitable cost and practical limitations.But well, good luck to her and her investors, I hope they get something useful out of it.

author: TimNJ
author_rank: Super Contributor
timestamp: August 12, 2014, 11:24:34 pm
content: The product is interesting and while it seems like it doesn't have a place in the current day, it might in the future with significant refinements/discoveries.But more than anything I'm just not a fan of her attitude. You can't be too smug or act like you just invented the wheel when you didn't...yet.

author: EEVblog
author_rank: Unknown
timestamp: August 13, 2014, 12:24:54 am
content: Quote from: TimNJ on August 12, 2014, 11:24:34 pmShe didn't even invent ultrasonic wireless power transfer, nothing new there at all I'm afraid.Although she seems to be the one one trying to pioneer it's use for consumer product charging.

author: SirNick
author_rank: Frequent Contributor
timestamp: August 13, 2014, 03:32:57 am
content: Quote from: bfritz on August 12, 2014, 10:58:33 pmThose quotes are fun, and illustrate a point, but they're also totally valid within a limited scope of time. In the early 80s, how many people WOULD use a personal computer? And how many really needed >1MB of RAM? Sure, now computers are ubiquitous and have GBs of RAM. Technology had to change for that to be feasible though.Vision is not the process of ignoring reality. Vision is having a goal and finding a way to achieve it. OTOH, daydreaming is just saying "gee it would be nice if..." They're not the same thing. Anyone can daydream, but vision takes some skill -- at least enough to distinguish the difference between "hasn't been done" and "can't be done (at least right now)".This wireless charging thing is a daydream ("imagine being able to charge all your devices transparently") because the driving forces behind it (as far as anyone knows, currently) have not found a way to overcome the fundamental limitations that have prevented the adoption of what is already a fairly well-understood phenomenon.

author: coppice
author_rank: Super Contributor
timestamp: August 13, 2014, 04:04:56 am
content: Quote from: bfritz on August 12, 2014, 10:58:33 pmPlenty of unworkable things get demonstrated, and the demonstrations actually work. Demonstrations are easy when you focus on the primary goal, and ignore the collateral effects. I can melt your cell phone with 2.4GHz or 5GHz RF transmissions, so supplying 1W to charge it is no big deal. Is that going to be acceptable in daily use, though?In write-ups about power by Wi-Fi I keep seeing comments like "This is Wi-Fi so its safe, unlike transmitting energy by microwaves". Are those made up by the journalists, or are the people behind COTA actually saying this?

author: vk6zgo
author_rank: Super Contributor
timestamp: August 13, 2014, 04:34:00 am
content: Quote from: bfritz on August 12, 2014, 06:38:27 pmI'm sorry,but nothing about Cota convinces me.The video is of some kind of "soft" popular science program like the old "Inventors" show we used to have on Australian TV.None of the the "judges" gave evidence of havinganyknowledge of Electronics (or any other Engineering discipline),& mainly just asked questions about the commercialisation of the device,as if its practicality was a foregone conclusion.Why was his hand covering the "receiver" all the time during the "demonstration"?The applause when he supposedly made the iPhone charge was a particular "red light" for me---most real people when confronted by something like this reserve their judgement,so it was probably "canned applause".The website says something like:-"never have to replace the batteries again"Well,yeah,you do have to,as rechargeables eventually die,whether they are being charged or not,& if the batteries are smaller because you have to fit the Cota stuff in,they will probably die earlier.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 13, 2014, 05:09:57 am
content: Quote from: coppice on August 13, 2014, 04:04:56 amWhile I agree with the general thrust of your comments,"melting" a mobile phone,as distinct from damaging the front end would require a quite profound amount of power,if you are referring to "transmissions",not "chucking the thing in a microwave oven".Remember,"gain" antennas don't produce an increase inactualpower---otherwise they would be an "over-unity" device!

author: coppice
author_rank: Super Contributor
timestamp: August 13, 2014, 09:14:15 am
content: Quote from: vk6zgo on August 13, 2014, 05:09:57 amI started out in radar. I'm used to profound amounts of power, and of melting things at quite a few paces by accident. Microwave ovens are for wimps.

author: eneuro
author_rank: Super Contributor
timestamp: August 13, 2014, 10:58:17 am
content: Quote from: bfritz on August 12, 2014, 10:58:33 pmImagine World full of light charging whatever you want (not only crappy cell phones) by Wireless TESLA Light Power (WTLP) by EneuroIt's real and works- just disconnected 230VAC 40W <1$ light bulb from the wall socket a few minutes ago, but cell phone and other things can be charged at rates > 1W without wires only just putting such things on the table, than light sensors can detect that something is above and adjust output power to it size.Dead simple and it works.All you need to do this is a few PV pannels and voltage regulator under cell phone.Even my old crappy Siemens cell phone which I like because of it is quite small <8inch2 can be charged using this bilions years old wireless light technology and everybody with basic electronics skiils can make simple circuit to use it at everyday basis, not only for marketing presentationsWhile its bottom area is about 5cm*10cm (2in*4in), it is about 0.5*10^(-3) m2.Now lets add reflectors and more efficient 100W light bulb than this used here where more then 90% of its energy is converted not into the light by heat-if we concentrate 100W power at a distance even of 0.1m (10cm) from glass table cover into 10cmx10cm box we have maximum input power 10kW/m2, than multiply by cell phone size we get5W. While we do not need big PV' pannels we could try to glue there more efficient used in satellite systems with lets say 20% efficiency, so we getQuoteBTW: In this photo multimeter shows only0.51Von100Rresistor in pararell to this small crappy garden solar panel worth <1$, but when this reflector is in other position than it goes to 0.75V-most of input power is lost in heat and not concentrated at all, but it easy to improove overall energy transfer andHERE IT IS 100%safe while we use everyday light to transfer wireless powerUpdate:Sharp Solar Cell Efficiency Record — Another One (44.4%)QuoteOne year agoBuild your own DIY solar powered mobile phoneFuture is now

author: steve30
author_rank: Frequent Contributor
timestamp: August 13, 2014, 03:08:59 pm
content: She mentions about how to be an innovator without having Aspergers. As someone with Aspergers Syndrome, I'm not sure whether I should be offended by that.

author: TimNJ
author_rank: Super Contributor
timestamp: August 14, 2014, 04:24:12 am
content: Quote from: steve30 on August 13, 2014, 03:08:59 pmI don't think its something she should have poked fun at, or even mentioned...if she was trying to be professional.

author: miguelvp
author_rank: Super Contributor
timestamp: August 14, 2014, 04:39:08 am
content: Quote from: TimNJ on August 14, 2014, 04:24:12 amShe comes more as "Entitled" than "Professional" so yeah, I would expect her to say things like that.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 14, 2014, 07:28:50 am
content: Quote from: coppice on August 13, 2014, 09:14:15 amSorry I misjudged you,but I keep running into people who should know better,who think they can take,say 10watts of RF energy & in some magical way"focus"it so "they can boil an egg".They seemingly have no idea of how a Parabolic Dish Antenna works,or of simple Optics,for that matter!Again,my apologies for thinking you were one of these people!

author: jeremy
author_rank: Super Contributor
timestamp: August 14, 2014, 07:51:59 am
content: Quote from: vk6zgo on August 14, 2014, 07:28:50 amOT, but I'm curious now, could you do it with some sort of phased array or mode-locking? Cooking things with low power that isI mostly deal with lasers, and if you focus it well (down to >= 1um), the spot of a blu-ray laser with only a few mA is hotter than the sun. You could vapourise a really tiny egg!

author: vk6zgo
author_rank: Super Contributor
timestamp: August 14, 2014, 09:51:44 am
content: Quote from: jeremy on August 14, 2014, 07:51:59 amNo,"hot"isn't the point.Grab a lit match--------hot,isn't it!But that match can't produce enough power to do any useful work,even if you can continuously light one match after another.The element in an immersion heater doesn't get anywhere near as hot as a match,but it can boil a litre of water in a few minutes.Cooking things requirespower,& you are still limited by how much power you start off with.Maybe you could burn a hole in an egg,but cook it---no!

author: eneuro
author_rank: Super Contributor
timestamp: August 14, 2014, 12:39:38 pm
content: Quote from: vk6zgo on August 14, 2014, 09:51:44 amNot huge power but longer time needed if there is good insulation from outside lower temperatures and heat created by absorbing low power energy can be accumulated.Put egg into something likewiki: Vacuum flask, calculate energy needed to cook it, whatever it means, while amount of absorbed energy counts not power used which will depend on outside temperature, insulation and expected time.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 14, 2014, 01:58:06 pm
content: Quote from: eneuro on August 14, 2014, 12:39:38 pmPower companies charge for energy,so it will still cost nearly as much to cook your egg as the high power/short time option.The losses are lower,but they happen over a longer time,so the increase in thermal efficiency doesn't count for as much as you would expect.And this method could not allow "focussed" RF power,(even if such existed),because of inherent losses in the flask material.

author: eneuro
author_rank: Super Contributor
timestamp: August 14, 2014, 02:58:41 pm
content: Quote from: vk6zgo on August 14, 2014, 01:58:06 pmI know what I can expect if I know ambient air temperature while in thermal solar concentrated solar power (CSP) estimated by Bird clear sky model from my sun tracker software it is now about 850W/m2:QuoteThere is huge influence on ambient air temperature in overall thermal solar energy conversion to heat water in 600L+150L boilers and without good insulation and good vacuum absorbers much more power needed to accumulate the same amount of energy and "cook" water, but it is off top and different storyBTW: It is focused RF power, while 3m in diameter parabolic mirror is used in this project so sun energy from area in the order of 7m2 close to 7kW input free energy from the sun with much higher efficiency than in PV panels is converted into water heat for everyday use

author: steve30
author_rank: Frequent Contributor
timestamp: August 14, 2014, 05:15:16 pm
content: Quote from: miguelvp on August 14, 2014, 04:39:08 amIt just seemed completely irrelevant to me, hence I'm not sure why she mentioned it. I'm not aware of technology innovation being more popular amongst people with Aspergers Syndrome than anyone else.

author: G7PSK
author_rank: Super Contributor
timestamp: August 14, 2014, 05:33:25 pm
content: Such a device would be illegal in the UK and the rest of Europe. It is a criminal offence to do anything that disturbed's bats without a special licence.Teenagers could also find such a device disturbing as well there is a device that emits ultra sound to make it uncomfortable for teenagers the idea is to prevent them from hanging around shop fronts and street corners.

author: SirNick
author_rank: Frequent Contributor
timestamp: August 14, 2014, 06:41:24 pm
content: At 40kHz? I remember playing with 20kHz tones in my teens, and most of what I heard was the "tick" as the tone started and ended. I could hear 18kHz well enough, but it rolled off pretty sharply above that. At twice the frequency, not sure I would hear anything at all.

author: TimNJ
author_rank: Super Contributor
timestamp: August 14, 2014, 08:05:42 pm
content: Yeah 40kHz is reallly up there. I'd say hearing 25kHz would be impressive for a young kid, though I have no scientific evidence to back that claim, but no human is going to hear 40kHz. Not to attack you, just sayin.

author: Precipice
author_rank: Frequent Contributor
timestamp: August 14, 2014, 08:24:30 pm
content: You're certainly going to hear 40KHz beating against 39KHz, though, if both sources are pumping out tens of Watts.Heck, you might manage to make really odd results by sitting between identical frequency 40KHz transmitters and moving your head to create a bit of opposing Doppler shift in each direction.High power ultrasound - it's really not benign stuff... But hey, fsck theexpertsnaysayers, she's got a 'great idea' and a pile of funding.

author: G7PSK
author_rank: Super Contributor
timestamp: August 14, 2014, 08:31:18 pm
content: Seems its 17KHZ. For teenagers and could be in a street near you.http://www.movingsoundtech.com/

author: TimNJ
author_rank: Super Contributor
timestamp: August 14, 2014, 08:31:24 pm
content: That's true, Sure the dB curve for human hearing rolls off real quick on those upper frequencies...but with enough power (ie uBeam) and other phenomena as you name...you'll definitely feel the effects.

author: P K
author_rank: Newbie
timestamp: August 15, 2014, 03:10:49 am
content: Anyone else thinking of this?

author: miguelvp
author_rank: Super Contributor
timestamp: August 15, 2014, 03:16:10 am
content: Quote from: P K on August 15, 2014, 03:10:49 amFixed it for you, remote linking sometimes is not the way to go

author: P K
author_rank: Newbie
timestamp: August 15, 2014, 03:18:47 am
content: Guilty; I had tried to Imgur it but copied the wrong link.I'm a horrible internet citizen.

author: SirNick
author_rank: Frequent Contributor
timestamp: August 15, 2014, 07:18:18 pm
content: What game izzat?

author: bookaboo
author_rank: Frequent Contributor
timestamp: August 16, 2014, 04:35:32 pm
content: Is there not a possibility of hearing damage regardless of the frequency? Does the brain tune out frequencies above whatever frequencies or do the moving parts of the ears themselves stop resonating?

author: coppice
author_rank: Super Contributor
timestamp: August 18, 2014, 01:12:12 am
content: Quote from: bookaboo on August 16, 2014, 04:35:32 pmLoud ultrasonic sound will cause hearing damage. If you have been in a place with loud ultrasonic sounds (a few industrial environments are like this) you might have experienced the weird effect of being in a quiet place, but having a sensation like there is a deafeningly loud noise. You might not hear these sounds, but when they are strong you definitely register them in some way. Does anyone know the physiology of what is going on there.

author: microbug
author_rank: Frequent Contributor
timestamp: August 19, 2014, 10:11:58 am
content: I read a magazine article about this once. Turns out that some ultrasound frequencies can affect your mood as well.Wikipedia page- presumably there must be a lot of power behind the sound for it to reach your inner ear through bone conduction.

author: eneuro
author_rank: Super Contributor
timestamp: August 19, 2014, 03:17:10 pm
content: Quote from: microbug on August 19, 2014, 10:11:58 amIt is interesting that it looks like to make music easy available via internet and storage capabilities of digital audio frequency sounds were cut in some music formats to this magic 20kHz, but it does not mean that music at higher frequences despite it is not recognized as sound does not affect our brains and in one of those references on mentioned above wiki page there is interesting article where EEG brain waves were measured as response to higher frequency sound tooPDF: Inaudible High-Frequency Sounds Affect Brain Activity: Hypersonic EffectAnother arguments (14 years ago) to forget about ultrasonic wireless chargingBTW: I used to ban to use cell phones close to head too, while nobody knows how it affects our brain, while it is electromagnetic radiation and I don't care someone says it is safe, while significant amount of radio power is needed to connect to GSM base stations at high radio frequencies and there are too many people interested in to have as many as possible customers paying bills for cheaper but longer calls connectionsIt is much safer and comfortable to use standalone microphone with ears headaset and keep this cell phone as far as possible away from our body or simply use internet calls at home if possible

author: sleemanj
author_rank: Super Contributor
timestamp: October 31, 2014, 06:59:16 am
content: 10 Million Bucks...http://www.bothsidesofthetable.com/2014/10/30/the-audacious-plan-to-make-electricity-as-easy-as-wifi/http://www.reddit.com/r/hwstartups/comments/2ku33v/ubeam_raises_10m_to_make_electricity_as_easy_as/

author: theatrus
author_rank: Frequent Contributor
timestamp: October 31, 2014, 03:15:56 pm
content: Even if a phased array ultrasonic delivery system worked, the power levels needed to charge a modern phone would be astronomical.

author: Artlav
author_rank: Frequent Contributor
timestamp: October 31, 2014, 08:04:25 pm
content: First CRTs, and now this...

author: idpromnut
author_rank: Unknown
timestamp: November 25, 2014, 07:41:30 pm
content: From the both sides site above: Is it safe? Well, it's what is used in pregnancies for imaging and the proximity detector on your car."… safe like sound waves." … This guy needs to stand behind/next to a 747 rev'ing up to full thrust and tell me after that sound waves are "obviously" safe.

author: Richard Crowley
author_rank: Super Contributor
timestamp: November 25, 2014, 09:06:35 pm
content: Quote from: idpromnut on November 25, 2014, 07:41:30 pmUltrasound imaging of biological objects (including pregnant women) is direct-coupled and further aided by a viscous fluid with reduces the transducer to tissue impedance-mismatch. It can not be honestly compared to sending power via ultrasound through the air.Ultrasonic proximity detection uses infinitesimal signals compared to what you would need to transmit useful amounts of power.

author: SeanB
author_rank: Super Contributor
timestamp: November 26, 2014, 06:07:18 pm
content: Quote from: idpromnut on November 25, 2014, 07:41:30 pmOHS came to the hanger one day to inspect, and as it so happened Mackie had taken a newly rebuilt 09K50 out to the engine test bay 500m away. Their SPL meter went to 150dB when he got to the full power setting. They turned it off before he got to the afterburner test cycle though, they were afraid they would break it. We were sitting there saying "What noise".

author: coppice
author_rank: Super Contributor
timestamp: November 27, 2014, 01:05:06 am
content: Quote from: Richard Crowley on November 25, 2014, 09:06:35 pmThe early medical ultrasound systems used a lot of energy, and the turbid fluids of the body can form some interesting random lensing effects. Combine those two, and people used to worry quite a lot about the sort of damage they might do. These days the energy is far lower, and damage seems unlikely.

author: mikerj
author_rank: Super Contributor
timestamp: April 27, 2015, 09:56:25 pm
content: Unbelievably, they have found investors dumb enough to part with $10 million to develop this waste of space. I know fools and their money are soon parted, but I thought investors tended to do at least some basic research before parting with 6 and 7 figure sums.uBeam’s Ultrasound Wireless Charging Is Real, And About To Be Really Funded

author: eneuro
author_rank: Super Contributor
timestamp: April 27, 2015, 10:53:14 pm
content: Quote from: mikerj on April 27, 2015, 09:56:25 pmThis smile is artificial or she trains how to tell investors that it wasfrom the beginingHmm, let us guess what thishard science problemis -lack of knowledge?To be clear, uBeam is still working on ahard science problemwhere unexpected setbacks can happen. There are plenty of reasons it might not be able to get as cheap, powerful, fast, and safe as Perry hopes. Butif it does, uBeamcould beone of the transformative technologies of our era. And that’s just the swing for the fences that investorsdream of.Why nowadaysExamining Einstein—precise experiments using lasers in space, rather than those bloody uBeam with pink blondy girl image?

author: Riotpack
author_rank: Regular Contributor
timestamp: April 28, 2015, 01:03:33 am
content: Just wack a charging cable at every table, 2x micro USB and 1 each of the 2 popular Apple ones.

author: kjs
author_rank: Regular Contributor
timestamp: April 28, 2015, 05:41:35 am
content: guys, calm down..... uBeam does exactly what the Vulture Capital in the US wants. If they pay themselves a good salary and make a lot of noise they will have nice 5-8 years and then move on to the next money-milking-scene.I was VP of engineering and then CTO in such start-ups and 99.9% of these VC guys including their so-called technical experts don't have the slightest clue. That's replaced with greed, arrogance and ignorance. They make a shitload of money from just managing and spending the money which they are not responsible for. Who cares whether those forced into investing there (some retirement funds, 401K) make losses? The big thing is mobile and IOT is currently coming up. That it will take years before a cellphone manufacturer would bet the company on something new and unproven from a nobody doesn't matter. If you are not into mobile or IOT you won't get money and who cares whether that thing has physics against it? It sounds GREAT! I would say congrats to the founders of uBeam for successfully playing with the system.

author: eneuro
author_rank: Super Contributor
timestamp: April 28, 2015, 05:53:27 pm
content: Quote from: Riotpack on April 28, 2015, 01:03:33 amWPT per room might work too, but forget about ultrasoundTesting something similar now, but whole room ground heating copper pipes with water... connected to a few MHz generator and will see what happends.At least copper will heat air in the room-if it will provide WPT electricity to small devices ~1m above ground the betterAnyway no plans to visit TED-I haven't got private jet yet and hate fly commercial airplanes full of depressed pilotsBut I have quite big yard behind house, so CNN, BBC,Discovery science will be able visit me in their helicopters at home at see how it works in practice

author: EEVblog
author_rank: Unknown
timestamp: April 29, 2015, 05:40:53 am
content: Update:Talk of $50M+ funding in the next round:http://techcrunch.com/2015/04/26/kill-the-cord/Note that Techcrunch are an investor in Ubeam, so yeah, totally impartial article.And still nothing demoed since the laughable veroboard prototype demo.

author: eneuro
author_rank: Super Contributor
timestamp: April 29, 2015, 01:57:01 pm
content: Quote from: EEVblog on April 29, 2015, 05:40:53 amYou have to click uBeam on right in oryginal link to see that Ubeam "inventors" probbaly are able to change the laws of physics to make it happenThey wrote:Our engineering team is comprised ofworld-class multidisciplinary inventors, where the word “impossible” is not part of our lexicon.Anyway, on this template page:http://ubeam.com/company/we can see another executive team members with... the same crappy photos cut and paste (ok-slightly different view on 2nd photo) from I've posted above from another article, where it looks like future CEO woke up in the middle of the night with this "great" idea (notice probably this CEO photo was made in the.. bedroom on second plane) and this was published later in "official" ubeam.com web page linked aboveOther executive team VP images also looks like were made in a very not proffesional way, eg. VIP Paul with shadows on the yellow wall, because of lack of good light to make this photoIf I didn't missed anything from ubeam.com template web page those three (yep 3 photos) are the only published on their "website".What can I say-nothing I'm speachless now after visiting uBeamofficial web page?BTW: Now realized that CEO face is actually square image and their web page designer was very creative to... change its shape to circleHowever, this domain could be available for sale soon, while they paid for this domain only up to AD 2017 and this idea is probably 10 years old, while uBeam domain name was registered AD 2005, but ok it could be taken by someone else beforehttp://reports.internic.net/cgi/whois?whois_nic=ubeam.com&type=domainDomain Name: UBEAM.COMRegistrar: GODADDY.COM, LLCSponsoring Registrar IANA ID: 146Whois Server: whois.godaddy.comReferral URL:http://registrar.godaddy.comName Server: NS75.DOMAINCONTROL.COMName Server: NS76.DOMAINCONTROL.COMStatus: clientDeleteProhibitedhttp://www.icann.org/epp#clientDeleteProhibitedStatus: clientRenewProhibitedhttp://www.icann.org/epp#clientRenewProhibitedStatus: clientTransferProhibitedhttp://www.icann.org/epp#clientTransferProhibitedStatus: clientUpdateProhibitedhttp://www.icann.org/epp#clientUpdateProhibitedUpdated Date: 24-mar-2014Creation Date: 06-oct-2005Expiration Date: 24-mar-2017

author: chicken
author_rank: Frequent Contributor
timestamp: April 29, 2015, 07:06:09 pm
content: QuoteHow the CEO looks, how professional their head shots are, or when their domain expires has nothing to do with the viability of their invention. Stick to physics and electronics, there's plenty of questionable material there.

author: Zero999
author_rank: Super Contributor
timestamp: April 30, 2015, 11:50:30 am
content: Quote from: G7PSK on August 14, 2014, 08:31:18 pmNot just teenagers. Plenty of young adults can hear that high. I'm 33 and can hear a cheap speaker connected to a signal generator running at that frequency. A proper tweeter connected to a power amplifier would be unbearable.

author: Delta
author_rank: Super Contributor
timestamp: June 24, 2015, 07:20:59 am
content: Here's a good little article about this scam, a bit less technical than Dave's debunking, but a bit more businessey. "people think that because they have money, they can buy their way out of basic physics. Not so. Physics always wins in the end."http://lookatmeimdanny.tumblr.com/post/101432017159/how-putting-10m-into-ubeam-illustrates-everything

author: EEVblog
author_rank: Unknown
timestamp: July 30, 2015, 12:46:33 am
content: WARNING: Reading the title of this article might ruin your day, or cause you to compulsively bash your head against the desk:http://fortune.com/2015/07/29/ubeam-meredith-perry-wireless-charging/and finally a photo of the prototype:

author: timofonic
author_rank: Frequent Contributor
timestamp: July 30, 2015, 01:56:22 am
content: Quote from: EEVblog on July 30, 2015, 12:46:33 amMy cynist inside myself makes me very happy. They are going to scam riches (at least the stupidest ones) at least the money will move to younger scammers.And maybe this will make a nice novel and a movie...

author: LabSpokane
author_rank: Super Contributor
timestamp: July 30, 2015, 02:47:03 am
content: My favorite Marc Andreessen quotes:QuoteMarc, can I have a job? Or at least can I have $13M? I won't give you wireless charging, but my personally-funded projects show more progress than Meredith's. How in the *&^!? can you give someone that kind of dough, get NOTHING in over four years, and still consider their job performance as "very well?" Meredith won't show you a prototype? Meredith hasn't even shown up on your doorstep to personally thank you and to demonstrate work-in-progress? That's a great investment?!!Oh, yeah, I remember now. There's a second round of funding coming and you can't wait to get your money out of this loser.QuoteFinally, something about uBeam we all can agree with. It's only viable in a fictional world. Well said, Mr. Andreessen.

author: EEVblog
author_rank: Unknown
timestamp: July 30, 2015, 03:03:17 am
content: I'm not sure how the press never pick up my blog post on it. For me it's #3 on google search for "ubeam"

author: bookaboo
author_rank: Frequent Contributor
timestamp: July 30, 2015, 07:04:27 am
content: Quote from: EEVblog on July 30, 2015, 03:03:17 amLazy journalism, the "wireless phone charging", "exciting startup", "young female entrepreneur" and "next Elon Musk" stuff is all excellent click bait. It would be a brave journalist that would stick his neck out and make the unpopular "bs" call, plus he would have to get it past his editor.Still, if I were you I'd fire off some emails offering an interview on the subject - you never know.

author: timofonic
author_rank: Frequent Contributor
timestamp: July 30, 2015, 07:13:53 pm
content: Quote from: EEVblog on July 30, 2015, 03:03:17 amAre you sure they don't know it's an scam? This is a scamming plot, with different parts involved.It happened before...

author: eneuro
author_rank: Super Contributor
timestamp: July 30, 2015, 10:48:55 pm
content: Quote from: EEVblog on July 30, 2015, 12:46:33 amProbably they spend all investors money to make this photo of... yellow sheet of paper, what ever it is, it must be something worth to seeNope, it looks like CEO of company who invested milions of virtual money doesn't have professional photograph and it looks like she made photo of this "prototype" using crappy phone, since thisPCB is on glass table on top of.... beer cans?Anyway, when I change parts of this article and exchange uname with.... it now makes more senseThe idea? Charge the battery of an electronic device from across the room—no wires necessary. The company is Eneur*o, based in Europe. And the man behind it all isElectric Neuron, its brilliant, ambitious, and occasionally overwhelming co-founder and CEO.Yep, I really need charge the battery of my RF wall radio switch, so... a few small PV solar cells will do the job-they are cheap and no need to mess with bloody soundNo wires necessary and better no need to even think about uidea like hipersonic chargingBTW: She spend some money for better bed and now her room looks better, but...those messy NASA astronauts pictures means?I could understand one photo, but two similar images side by side-there is no creativity in this design and red carped on her bed maybe is fine for pink blondy girl, but she should watch more Bollywood hits to make her room a look worth to show on any website-maybe install webcam and change company name to uXXXu to make profits?

author: EEVblog
author_rank: Unknown
timestamp: October 06, 2015, 02:07:41 am
content: Another $10M bucks into the UBeam black hole:http://fortune.com/2015/09/30/ubeam-wireless-charging-funding/

author: theatrus
author_rank: Frequent Contributor
timestamp: October 06, 2015, 02:51:35 am
content: A company of that scale does not need a CFO. Where is the prototype?

author: coppice
author_rank: Super Contributor
timestamp: October 06, 2015, 03:05:01 am
content: Quote from: EEVblog on October 06, 2015, 02:07:41 am4 years in. Not even a proof of concept demo (the WiFi charging people at least achieved that, although the demo showed the impractically), let alone a demo of something like a product. Still they can raise $10M. Nice.To be fair, it sounds like that $10M is not really fresh funding. Its some kind of extension of the funding from the people who already put $13M into this. You never know. A closed group like that might have already seen an amazing near product demo that pumps hundreds of watts of supersonic energy into the air so a watt or two can be pulled out to slowly charge a phone.

author: EEVblog
author_rank: Unknown
timestamp: October 06, 2015, 03:46:43 am
content: Quote from: coppice on October 06, 2015, 03:05:01 amThere is a prototype, there has been a photo of it, and it looks to do the business, exactly what you'd expect such a thing to look like.Few would doubt that they have a working prototype, that's the easy part. The hard part is actually making ita) Legalb) Not dangerousc) Power efficient enough that it's not just a stupid waste of energy.d) Solving the steering probleme) Solving any interference problemsf) Making it cheap and simple enough for Joe Averageand maybe more...

author: coppice
author_rank: Super Contributor
timestamp: October 06, 2015, 03:49:19 am
content: Quote from: EEVblog on October 06, 2015, 03:46:43 amI saw something pushing a few microwatts across a room, which is not novel at all. Is there something that pushes enough energy to actually be considered a demonstration of charging a phone?

author: Delta
author_rank: Super Contributor
timestamp: October 06, 2015, 04:01:08 am
content: Is there any way to make money off this ridiculous project when it fails? ie like short selling shares in a company you know will go down the pan?

author: LabSpokane
author_rank: Super Contributor
timestamp: October 06, 2015, 04:27:38 am
content: QuoteSee what, Meredith? I've seen a "prototype" made out of eBay ultrasonic transducers that moved a voltmeter needle. Nothing more. To my knowledge, no one has ever seen a demonstration showing your device transmitting a meaningful amount of power over a realistic distance.

author: EEVblog
author_rank: Unknown
timestamp: October 06, 2015, 05:24:21 am
content: Quote from: LabSpokane on October 06, 2015, 04:27:38 amPrevious page in this thread:

author: coppice
author_rank: Super Contributor
timestamp: October 06, 2015, 05:32:46 am
content: Quote from: EEVblog on October 06, 2015, 05:24:21 amAs far as I am aware that's just the picture they've been using in their blurb. Has anyone ever seen that hardware being demonstrated? The only reports I remember of demonstrations were at the microwatt level, like remote control devices have been doing since the 1960s.

author: vk6zgo
author_rank: Super Contributor
timestamp: October 06, 2015, 09:39:26 am
content: Of course,if manufacturers made their "devices" with removable battery packs,you could always keep one charged & swap them as required.No silly remote charging needed!

author: EEVblog
author_rank: Unknown
timestamp: October 06, 2015, 11:22:34 am
content: Quote from: coppice on October 06, 2015, 05:32:46 amNo.But clearly a decent looking prototype of some sort does exist that appears to use beamforming as they have said. I'd be surprised if they can't transfer a few watts in a demo.Doesn't mean it's in any way commercially viable though. It's as dumb an idea as it ever was.

author: EEVblog
author_rank: Unknown
timestamp: October 06, 2015, 11:24:06 am
content: Quote from: vk6zgo on October 06, 2015, 09:39:26 amOr simply use one of those Qi charging pads that are super cheap, efficient, have crazy low standby power, and are simple and reliable

author: DanielS
author_rank: Frequent Contributor
timestamp: October 06, 2015, 03:24:18 pm
content: Quote from: EEVblog on October 06, 2015, 11:24:06 amQi is still nowhere near as cheap, efficient and low standby power as a decent wired 5V adapter or just plugging into something that already has 5V on a USB port like a PC, hub or monitor with built-in hub.

author: Delta
author_rank: Super Contributor
timestamp: October 06, 2015, 03:35:13 pm
content: Given that in some countries (Oz for example) linear power supply plugpack/wallwarts are being banned to save a Watt or two, why on earth are hopelessly inefficient wireless charging systems even being contemplated?

author: LabSpokane
author_rank: Super Contributor
timestamp: October 06, 2015, 07:47:24 pm
content: Quote from: EEVblog on October 06, 2015, 11:22:34 amI honestly would be shocked if they could transfer 5W over 10m with that setup. I realize that is supposed to be some type of representation of a phased array, but if it worked, there would be far more info than an un-captioned photo.

author: eneuro
author_rank: Super Contributor
timestamp: October 06, 2015, 10:46:23 pm
content: Quote from: LabSpokane on October 06, 2015, 07:47:24 pmLooking into latest "lab" photo from linked fromhttp://fortune.com/2015/09/30/ubeam-wireless-charging-funding/there is some progress-they have a "lab"However it looks like uBeam is still not used even to provide light to "lab" desk, but...IKEA lamp in the corner does provide enougth light to serious work?However, this new "lab" photo was at very low quality, so I had to slightly enhance it to higher resolutionWhat the hell, there is no gym or fitness room with swimming pool in this uBeam "lab" facility or she doesn't care about her image and only wear black suit to look slim?Anyway, my guess is this huge funding is only made in virtual cash written only on press webpages, because of I do not believe that rich peaople might be such stupid to invest in something such useless like this else than their timeThere is nothign in the background at the size of 1inch2 (2.5cm x 2.5cm) PCB which could be usable to mount on cell phone back. etc, so still two 1inch2 solar PV panel and 100W light bulb under glass desk could be the winner and no uBeam needed

author: EEVblog
author_rank: Unknown
timestamp: October 06, 2015, 10:53:39 pm
content: Quote from: Delta on October 06, 2015, 03:35:13 pmBingo, that's why, even if it worked, it's a fundamentally dumb idea. It might ultimately have some niche application, but it will not fly in the consumer world.

author: vk6zgo
author_rank: Super Contributor
timestamp: October 06, 2015, 11:50:02 pm
content: Quote from: EEVblog on October 06, 2015, 05:24:21 amA K-mart aluminium cosmetic case,sitting on some dog food cans,with a couple of poorly drawn renditions of an ultrasonic beam,one apparently coming out of one end of the handle!Or are the dog food cans the transducers?I've seen better fake technology in a 1960s Dr Who episode--& they were terrible!

author: zapta
author_rank: Super Contributor
timestamp: October 07, 2015, 04:11:37 am
content: ubeam related pictures. In the one below, the two breadboards hold the transducer array. May be the demo they show to potential investors.https://www.google.com/search?q=ubeam+power&es_sm=119&source=lnms&tbm=isch&sa=X&ved=0CAkQ_AUoA2oVChMI99fytb2vyAIVhymICh23-wFE&biw=1336&bih=646Their job postings hints on the technologies they are targeting. 2D piezo electric array with beam formers (not require for the parallel plates in the demo above). This thing is going nowhere commercially.http://ubeam.com/careers/acoustics-piezoelectric-engineers/

author: eneuro
author_rank: Super Contributor
timestamp: October 07, 2015, 07:36:00 am
content: Quote from: zapta on October 07, 2015, 04:11:37 amYep, with multimeter showing... rectified voltage accross bulky capacitor, while 1M-10M multimeter is the ONLY load in this wireless energy transferA long way to turn on power LEDs this way

author: amyk
author_rank: Super Contributor
timestamp: October 07, 2015, 08:23:15 am
content: For the record, that's a240W car audio ampwith the branding carefully removed...Two hundred and forty watts. I don't know how much of those they're using to transmit... less than 1W at the other end?There appears to be a big linear bench power supply connected to the amp. Unfortunately the most important part, the input voltage/current, is not visible in the images/video I could find (anyone else have better luck?)

author: coppice
author_rank: Super Contributor
timestamp: October 07, 2015, 08:39:10 am
content: Quote from: amyk on October 07, 2015, 08:23:15 amWhilst they appear to be using a pretty high power amp, that planar array of 10 little piezo devices connected in parallel (not phased for beam forming) don't look like they could cope with a great deal of power.Its interesting that they use a similar planar array of 10 transducers as the receiver. Wouldn't they need something omni-directional? Its hard to see how they could beam form a passive receiver, and an active one would have a major less than unity power transfer problem.

author: vk6zgo
author_rank: Super Contributor
timestamp: October 07, 2015, 09:34:19 am
content: Remember,the 240watt power output of a car audio amp is pretty much a "pretend rating"!The "steady state"or "average" power output will be lower,probably considerably so,even at audible frequencies.It is anyone's guess how well it does at ultrasonic frequencies.

author: EEVblog
author_rank: Unknown
timestamp: October 07, 2015, 09:38:31 am
content: Quote from: DanielS on October 06, 2015, 03:24:18 pmSure, but it's wireless, that's the point.

author: EEVblog
author_rank: Unknown
timestamp: October 07, 2015, 09:45:44 am
content: Quote from: zapta on October 07, 2015, 04:11:37 amNo, that's the original one she and someone else hacked together right at the start. She didn't even know the difference between voltage and power back then (no joke).Unfortunately investors were sucked into thinking that demo was legit.I'm sure they have a thoroughly impressive demo now, as seen in the photo above of the phased array elements.

author: coppice
author_rank: Super Contributor
timestamp: October 07, 2015, 09:48:50 am
content: Quote from: vk6zgo on October 07, 2015, 09:34:19 amThat amp is rated at 2 x 50W RMS stereo, with its 3dB point at 30kHz. Lets assume they use a lowish frequency like 30kHz, to minimise the losses. One channel of this amp should still be able to push out 25W, if the impedance of the load is suitable. This is a not inconsiderable amount of power for something which was shown doing nothing more than reading an output voltage into a high impedance. This is, of course, a crude demo without proper beam forming. Hopefully they can do a little better,

author: EEVblog
author_rank: Unknown
timestamp: October 07, 2015, 09:51:39 am
content: They spun a $1M+ ASIC too:https://www.linkedin.com/profile/view?id=AAIAAABnYf8BaHkGo0eOV-W4XpRb2sS4usSv0v4Quote

author: vk6zgo
author_rank: Super Contributor
timestamp: October 07, 2015, 10:43:37 am
content: Quote from: coppice on October 07, 2015, 09:48:50 amI'm sorry to be pedantic,but there is no such thing as "RMS Power".RMS is a convenient fiction used for ac voltages & currents to allow us to use the standard DC Power formula P=VI.The product ofIrms xVrms or (Irms)x R is known as Average power.

author: DanielS
author_rank: Frequent Contributor
timestamp: October 07, 2015, 02:20:23 pm
content: Quote from: vk6zgo on October 07, 2015, 10:43:37 amIt isn't just a "convenient fiction" since the power dissipated by a resistive load or wiring fed by an arbitrary waveform is P = RTot* IRMS2which has tons of non-fictional uses when sizing wiring for motors, transformers, power distribution systems, etc.

author: coppice
author_rank: Super Contributor
timestamp: October 07, 2015, 06:11:31 pm
content: Quote from: vk6zgo on October 07, 2015, 10:43:37 amIts really sine wave power, but it usually gets listed as RMS power.Quote from: vk6zgo on October 07, 2015, 10:43:37 amThe RMS of a waveform is highly meaningful in many cases, including voltage and current waveforms. However average power is only equal to RMS voltage times RMS current in a very specific case. P=VI, where V and I are RMS values, is not a very useful formula in general, so that is certainly not why RMS voltage and current are interesting.

author: zapta
author_rank: Super Contributor
timestamp: October 07, 2015, 06:24:59 pm
content: Some people refer to RMS s continuous or sustained (vs peak). In both cases it's based on some average of abs(v).

author: Marco
author_rank: Super Contributor
timestamp: October 07, 2015, 07:12:33 pm
content: The big problem with piezo is impedance matching. MEMS versions of electrostatic speakers would be better.Even with a phased array of state of the art ultrasonic transducers getting high efficiency is fantasy simply due to transducer losses.

author: eneuro
author_rank: Super Contributor
timestamp: October 07, 2015, 07:57:44 pm
content: Quote from: Marco on October 07, 2015, 07:12:33 pmWhat about magnetic transducers like this one, which I wanted to use as energy harversting deviceHowever, those magnetic transducers have below 10kHz resonant frequency and to make sound I drive them directly from MPU using simple transitor based full bridge low power AC amplifier output:BTW: If uBeam finds this idea usefull, do not forget donate via Bitcoin my sound energy harversting project too -I don't need any $1M to complete this project, so 0.1% of $1M will be fineMaybe I will help you make uBeam investors even more happy-they will get for their $10M free sound energy - no need for bulky high power sound source

author: coppice
author_rank: Super Contributor
timestamp: October 08, 2015, 03:01:07 am
content: Quote from: Marco on October 07, 2015, 07:12:33 pmI wouldn't say impedance matching is a big problem. You definitely need a good impedance matching device between a piezo transducer and air, but those exist. Morgan technical ceramics make transducers with good matching, and their name is actually mentioned in ubeam's patent applications. There have been various attempts to make MEMS based ultrasonic transducers, but we still use piezo in almost every case today. Things could change, but so far MEMS has failed to be compelling.If you send ultrasound between two piezo transducers in water, where the impedance match with the medium is naturally not too bad, you can get pretty good efficiency. The awful efficiency you typically get propagating into air is mostly due to the impedance match. Match the impedance well and you can probably get tolerable efficiency propagating into air. The patent applications from ubeam in 2012 talk about getting 40% efficiency, but I suspect that figure was pulled out of the air.

author: lincoln
author_rank: Regular Contributor
timestamp: October 08, 2015, 04:56:38 am
content: Quote from: eneuro on October 06, 2015, 10:46:23 pmWhy so salty? Its 10x the lab that battaro has...

author: vk6zgo
author_rank: Super Contributor
timestamp: October 08, 2015, 05:52:09 am
content: Quote from: DanielS on October 07, 2015, 02:20:23 pmExactly"RMS allows us to use the DC power formula P=VI & its derivatives in AC circuits.I don't know if the "Ancients" did the experiment first,then the Maths,or the other way around.Maybe they just compared how long DC & AC took to boil water,but I think it is more likely that they used awater cooled resistive load with water flowing through it at a known rate.They then measured the temperature rise of the water & knowing that & the flow rate,determined the power dissipated in the load.By adjusting the AC current into the load until the calculated power was the same,they could say that current had the same effect as a DC current which by I^2*R, would produce the same power.They then either went away, elated that the experimental result matched the Maths ,or went away to see if the Maths agreed with those results.

author: vk6zgo
author_rank: Super Contributor
timestamp: October 08, 2015, 06:18:48 am
content: Quote from: coppice on October 07, 2015, 06:11:31 pmOK,things get messy in reactive circuits,but P=VIwasderived from a purely resistive case,& there are many situations where we can assume a resistive load.P=VI must always apply in a resistive load situation if it applies in any.Most of the time we use the derived terms,but all of the other power formulae are derived directly from P=VI.The only reason I used P=VI on my posting was that it is less messy to type.

author: jrward
author_rank: Newbie
timestamp: October 08, 2015, 08:07:45 am
content: I did some contract PCB design work for uBeam several years ago. I never thought they would have raised this much money. They can absolutely transmit power over ultrasound (I'm not sure how much), but it seems impractical as many people point out. I'm not sure they deserve some of the vitriol on this thread and it makes me wonder why we engineers have such an aversion to hype. It seems like the general public gobbles it up.I'm torn. I'm trying to start my own company right now and I'm trying to fight my natural engineer aversion to hype. To sell something, you have to make it sound like it is some revolutionary idea, that only you can carry out this dream. How do we as engineers "cross over?" I don't want to sit in a cubicle for the rest of my life...

author: coppice
author_rank: Super Contributor
timestamp: October 08, 2015, 08:42:36 am
content: Quote from: jrward on October 08, 2015, 08:07:45 amMost people here tend to just laugh at most impractical ideas. I think the vitriol for ubeam stems from the obnoxious attitude its founder.

author: coppice
author_rank: Super Contributor
timestamp: October 08, 2015, 09:14:16 am
content: Quote from: vk6zgo on October 08, 2015, 06:18:48 amP=VI is the basic power formula ONLY when V and I are instantaneous values. Nothing is derived from P=Vrms.Irms. That formula gives you apparent power, which is a fairly meaningless quantity for anything but a resistive load. For a pure sine wave source, and a pure linear load you can draw a nice triangle of active power, reactive power and apparent power, but that third side of the triangle doesn't mean much. However, as soon as there is any distortion the whole triangle idea falls apart. A water heater is pretty linear, but try an incandescent light bulb. You'll probably get >10%THD, and things get complex. In reality few loads you meet today looks like the simplistic active, reactive, apparent triangle.RMS is not some construct for dealing with voltages or currents. It one of the most fundamental statistical measures of varying functions, and crops up all over the place in physics and chemistry.

author: vk6zgo
author_rank: Super Contributor
timestamp: October 08, 2015, 11:54:57 am
content: Sorry,I misunderstood your point.I also stuffed up with"OK,things get messy in reactive circuits,but P=VI was derived from a purely resistive case,& there are many situations where we can assume a resistive load."What I should have said was that P=VI was derived from the purely resistiveDCcase,with P=I^2R,& V^2/R,further derived from that.(those are the "derived" formulae I was referring to)Irms & Vrms were further determined by calculation & experiment.And,yes,I am aware of the use of rms in other fields---I used it to find the area under the curve in Mathematics.RMS current & voltage have been used extensively for over 100years,so theydostill have their place.In the case of a Radio Transmitter,a substantially resistive Test Load is used to determine the RF output power.This can be,& is,often done using P=I^2R.or V^2R with lower power equipment.(Larger installations often use a water cooled Test load,with average power determined by flow rate & temperature rise)A real antenna is then matched to the Transmitter,so that it looks as near to resistive as possible,so the Transmitter can deliver the same power output as to the Test Load.The incandescent lightbulb case really only applies during the initial warm up period--once it is hot,it is a pretty stable resistance.My original comments were a bit "dumbed down" to make the point about so-called RMS Power.I never intended to get into an esoteric "off topic" conversation, so if you don't mind, I'm going to 'bail" on it.

author: coppice
author_rank: Super Contributor
timestamp: October 08, 2015, 01:19:58 pm
content: Quote from: vk6zgo on October 08, 2015, 11:54:57 amTry looking at the current waveform for an incandescent lamp with a THD meter. Its 10% to 20% all day long. The temperature really varies that much 100 or 120 times a second.

author: eneuro
author_rank: Super Contributor
timestamp: October 08, 2015, 03:21:21 pm
content: Quote from: lincoln on October 08, 2015, 04:56:38 amProblem is it doesn't look like lab where someone is working on something, but... it is rather like for sale exposition with items no longer neededOne monitor in lab might have only pink girl to tweet on facebook-Engineerwill have at least two, three...She was unlucky, because of by showing this big crap PCBs on this desk, that they still has nothing to show, but completly not ergonomic room corner, because of this can't be called lab-it is nothing there and thay also closed windows, maybe to do not show... private garden with her dog playing with her catBasicly, in $10M donated company one might expect more to see, especially when it is showed not in city tabloid, but serious business claims while it looks like a expensive joke

author: Howardlong
author_rank: Super Contributor
timestamp: October 08, 2015, 03:41:37 pm
content: Quote from: vk6zgo on October 07, 2015, 09:34:19 amEither way, that would be into an appropriate low impedance load like a couple of 4 ohm speakers. I'll bet you that for someone who struggled with the concepts of voltage and power, it's unlikely they'd be capable of developing impedance matching and maximum power transfer.All that was demonstrated there was a remote control from the 1970s. The amp might've increased the peak-peak voltage across the transducer array, but I doubt there was much more than a watt or so going through those transducers.Quote from: eneuro on October 06, 2015, 10:46:23 pmWhat is apparently bizarre is the absence of reasonable due diligence when VCs piss cash into these things. To be fair, the angel investors don't really care too much about the ultimate viablility of an idea, only that there's a reasonable chance they can palm it off to some unsuspecting soul at a later date at a serious profit before the emperor reveals himself in public. If that means the VCs pulling on the resources of a PR firm and using their connections (eg, Tech Crunch) to big up largely empty claims, then so be it. To them it's a numbers game: if you throw enough money at enough ideas, like monkeys and typewriters, surely one or two of them will succeed. As only about 25% of VC investments succeed, you can imagine the amount of ROI subsequent investors will be raping from the few poor sods with the real ideas that are successful to make up for those investments that aren't.I recently read an article about a day in the life of a VC "investor" (in quotes, because it's not necessarily their own money they're pissing away), the apparently self-assured writer boasted of spending a day in back-to-back meetings with potential startups, with fifteen minutes to half an hour for each, seemingly akin to speed dating. They might also choose to float the idea with their own (self-)appointed buddy "expert in the field" who'll give their view after an equally cursory glance. It seems like that's about it, if it doesn't smell like a Pommie's sock after such an in-depth investigation, they'll call their investor buddies up for a game of golf and the deal is all but done. All that's left is a few well-placed articles in the press bigging up their latest investments for their fan boys.If the VC investors were so bloody good, they wouldn't be suffering a 75% failure rate: that's not a figure to be proud of IMHO.

author: jrward
author_rank: Newbie
timestamp: October 08, 2015, 05:48:37 pm
content: Quote from: Howardlong on October 08, 2015, 03:41:37 pmA lot of companies are getting money these days that shouldn't. I think it is down to the same basic cause of the subprime mortgage crisis. With interest rates so low pension funds, endowments, and people with massive wealth need to put their money somewhere to make a decent return. 8 years ago, it was mortgaged-backed securities. The banks needed more mortgages to bundle up and sell to the financial firms so they started granting dodgy mortgages. It's the same thing now but with VCs. VCs need someplace to park the money they get from investors so they can go on and get more investment. While they often put some of their own money in, VCs for the most part are spending other people's money. The more money they have under their control, the bigger their management fees so there is this incentive just to spend spend spend.The time horizons for lots of these investments are so long that we haven't seen many big failures yet. I'm sure it will happen and I don't think it will drag the whole economy down, but it might be harder to find a tech job for a few years.

author: DanielS
author_rank: Frequent Contributor
timestamp: October 08, 2015, 08:57:55 pm
content: Quote from: vk6zgo on October 08, 2015, 05:52:09 amSince integral calculus was discovered long before electricity became an actual science instead of a curiosity or unexplained phenomenon, my guess is that math came first.

author: eneuro
author_rank: Super Contributor
timestamp: October 10, 2015, 06:49:31 pm
content: Not sure if it was linked there but quite fresh (2 days ago):Posted Oct 8, 2015 by Josh Constine (@joshconstine)uBeam Finally Reveals The Secret Of How Its Wireless Charging Phone Case Works SafelyYou can't miss this especially section: "How uBeam Is Safe" where someone linked.... RF, visulal light and gamma rays frequencies spectrum while talking about ultrasoundHopefully, in comments you can find they have strong competitor already operating and charging devices using RF :http://www.energous.com/overview/, so probably "u bullshit Beam" can only have a dream and nothign else

author: IanB
author_rank: Super Contributor
timestamp: October 10, 2015, 09:59:01 pm
content: Quote from: jrward on October 08, 2015, 08:07:45 amIt shouldn't be about an aversion to hype. Hype is a marketing tool, and if you want to be in business you'd better be good at marketing.The problem for engineers is when people make exaggerated claims for things that patently can't do what is claimed. It's not the hype that is the problem, it is the bullshit...

author: chicken
author_rank: Frequent Contributor
timestamp: October 10, 2015, 10:03:47 pm
content: Quote from their website: "Ultrasonic energy (energy from ultrasound) is the only type of energy that can safely and reliably transmit energy wirelessly; thus it's the only type of energy that can be used for over-distance wireless power transmission."http://ubeam.comAnd the hyperbole only gets better from there on..

author: EEVblog
author_rank: Unknown
timestamp: October 10, 2015, 10:51:48 pm
content: Quote from: eneuro on October 10, 2015, 06:49:31 pmJust seems to be more talk. Where is the data? Where are the demos of it charging a phone that moves randomly around a room? How efficient is it?

author: EEVblog
author_rank: Unknown
timestamp: October 10, 2015, 10:54:18 pm
content: Quote from: IanB on October 10, 2015, 09:59:01 pmYes, this. We understand hype, it's part of the game. But BS should not be part of the game. If you make claims, you back them up with demos and data. They have had what, 3 years to demo something tangible, but still nothing.

author: EEVblog
author_rank: Unknown
timestamp: October 11, 2015, 06:13:38 am
content: Looks like there are some figures to work with on the website now:QuoteBingo. If someone can find out what the FDA exposure limits are, then it's 50 times less than that at maximum.and:QuoteSo presumably the uBeam is at least 1W output? (but under what conditions?)

author: crispy_tofu
author_rank: Super Contributor
timestamp: October 11, 2015, 06:27:12 am
content: *sniff*Hmmm...Quote from: coppice on August 08, 2014, 02:19:12 am

author: coppice
author_rank: Super Contributor
timestamp: October 11, 2015, 06:49:20 am
content: Quote from: EEVblog on October 11, 2015, 06:13:38 amI think the only FDA figures will relate to the direct injection of ultasound into flesh, and for frequencies well above 1MHz. Things like ear damage aren't an issue there.Quote from: EEVblog on October 11, 2015, 06:13:38 amThe whole article is written to carefully avoid saying anything important. Things like "99.9% of uBeam's emitted ultrasound will bounce off the skin" ignore what it will do to your ears. Most of the safety related comments dodge the real issues like that. The whole thing about shutting down when line of sight is blocked is pretty funny. The writer seems to imagine an ultrasound beam as a hard edged beam, like a collimated light source.It originally seemed like they were using a frequency only just above human hearing. The article makes it sound like they are now taking the hearing of animals into account, and have pushed the frequency much higher. That won't be good for efficiency. Above 100kHz the losses in air are massive.

author: lm3baker
author_rank: Contributor
timestamp: December 07, 2015, 10:31:42 am
content: Quote from: IanB on October 10, 2015, 09:59:01 pmThe problem for engineers is that they have been in the situation where marketing, management or their boss has oversold the customer on something they are now required to deliver, or the situation of assessing contracts/bids/offers by suppliers. To an engineer (at least one not in management), hype andis something they must expend time and effort filtering out.Sales in the b2b technical field is about communicating what the capabilities and limitations of both companies are because work comes with risks and requirements for each party. Door-to-door sales and showmanship are a completely different ballgame, where the customer purchases something with zero guarantee of fitness for purpose and zero recourse if it turns out to be junk.

author: GNU_Ninja
author_rank: Regular Contributor
timestamp: December 07, 2015, 10:42:29 am
content: What about the health risks?http://www.hse.gov.uk/research/crr_pdf/2001/crr01343.pdfUltrasound makes my teeth itch

author: lm3baker
author_rank: Contributor
timestamp: December 07, 2015, 10:45:42 am
content: Quote from: jrward on October 08, 2015, 05:48:37 pmMy theory is that the VCs involved see this as a marketing exercise. It's something they can show off to their investors as a technical looking, edgy, thingamabob that they are investing in. All the publicity surrounding it whether negative or positive gives an air of credibility, and recognition. The list of patents surrounding ultrasonics (a patent fence of sorts) are bankable IP (even if not practical IP), the mangers get a cut from moving money around, the unrecoverable losses made by the company are small (well, small for a VC firm anyway), the inventor gets a nice salary and everyone wins. Welcome to the near-future of STEM!

author: lm3baker
author_rank: Contributor
timestamp: December 07, 2015, 10:53:22 am
content: Quote from: GNU_Ninja on December 07, 2015, 10:42:29 amNice find there. I sometimes work with rather noisy SMPS in the 16-24kHz range. A colleague already wears earmuffs (noise reducing ear protection), might have to adopt the same practice.

author: Fungus
author_rank: Super Contributor
timestamp: December 07, 2015, 11:19:03 am
content: Quote from: GNU_Ninja on December 07, 2015, 10:42:29 amI love the way she spends time defending herself from people who imagine her imaginary product will be harmful.