uBeam.flv

Perry first stood a couple of yards from a large white box emitting ultrasound waves, and used a device that glowed red when it was in the waves' path. She then grabbed an Android smartphone in a large and bulky black case, and held it up in that path. When she did so, a large battery charge counter on the screen showed that it was indeed charging. Of course you can transmit some power that way. But how much? And what's the efficiency? Here's their previous demo, from 2011.[1] What they had then was a bunch of cheap ultrasonic transducers [2] aimed at each other. Those used to be popular for hobbyist robotics. Some unspecified amount of power was transmitted about two feet. Probably a few milliwatts. The last time UBeam published numbers, they claimed to be generating a few kilowatts of sound power. Such things are usually used as weapons systems (see LRAD) or welders. You don't want to be in a kilowatt ultrasonic beam. The energy mostly ends up as heat. This technology is either too low power to be useful or, if pumped up to useful power levels, too dangerous. [1] ▶ this video [2] link

They had a working demo in 2012. Here it is.[1] You're looking at a single big ultrasonic transducer sending to a bunch of little ones. The little ones are the same ones RobotShop sells.[2] They're very vague about how much energy went in and how much came out. The big heat sinks on the sending side suggest that a few hundred watts are going in. The meter on the receive side is just showing voltage, so there's no indication of the actual energy transfer. There's no beam forming or steering. Anybody could reproduce that demo, but it doesn't prove much. [1] ▶ this video [2] link

Well, either it works or it doesn't. What's there to talk about? It's not that they're doing rocket science. > "But even amid a tidal wave of publicity, the company has never publicly demonstrated a fully functioning prototype of its system." This is what I don't get - how the hell did they manage to get investors? I mean, ultrasound charging isn't magic, anyone who knows their stuff around EE should be able to throw together in a month a simple prototype of the tech to show to the investors. That is, a prototype that actually charges a phone, not this[0] which a) doesn't really charge the phone, and b) seems to be geared towards confusing people clueless about electricity. The fact that they didn't, after 4 years, produce anything suggests that they don't even have anyone on board who knows this stuff, so why are they getting money? Seriously, I think I'm gonna plug my IRC bot to TTS and go raise money for my AGI startup. [0] - ▶ this video

From Arrington's blog: > In a year or so when this thing is productized you’ll be hearing a lot more about Mary. As you note, that was written on May 23, 2012, more than 2 years ago. According to this article[1], the company is now aiming to be selling "by 2016." This suggests there was either a misunderstanding about the time required to develop a commercial product, or developing a commercial product has taken a lot longer than anticipated. What's interesting to me is that the recent photo from the New York Times[2], which Mark Suster also included in his blog post[3], doesn't on the surface seem to show substantial progress from what was being demoed back in 2011[4][5]. Charging a single phone from a couple of feet away is not what's being promised. [1] link [2] link [3] link [4] link [5] ▶ this video