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The uBeam FAQ

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PaulReynolds:

--- Quote from: Poe on July 01, 2019, 06:56:54 pm ---Just saw the latest EEVblog video.  At 13minutes in, Dave is saying the LED pattern doesn't follow the movement.  Couldn't this be attributed to the phased array's tracking error?  That is, it's changing where the array is pointing as the turret sweeps the room to keep power at the target.

Disclaimer: I've read no information on this thing or any of these posts, just was the first thought I had.

--- End quote ---

Could be several things. One of their arrays appears to have no steering capability at all, and only points forward, possibly doing some change of the focal depth but uncertain. It could also be that the tracking just wasn't keeping up with the sensors movement. Hard to say, but don't read too much into it, so many of the images and videos are cut and devices swapped around it's hard to keep track, which was possibly deliberate...

EEVblog:

--- Quote from: Poe on July 01, 2019, 06:56:54 pm ---Just saw the latest EEVblog video.  At 13minutes in, Dave is saying the LED pattern doesn't follow the movement.  Couldn't this be attributed to the phased array's tracking error?  That is, it's changing where the array is pointing as the turret sweeps the room to keep power at the target.

--- End quote ---

No, that transmitter has no phased array tracking, they have another bigger model for that. This is mentioned and demonstrated in the other stage demonstration video.

Poe:

--- Quote from: EEVblog on July 03, 2019, 05:34:20 am ---...
No, that transmitter has no phased array tracking, they have another bigger model for that. This is mentioned and demonstrated in the other stage demonstration video.

--- End quote ---

Now I'm even more confused. 

If the emitter isn't tracking and just using phased array focusing, then the LED pattern should completely disappear as the turret moves away.  If they're not using phased array focusing, then their performance will be crap (exponentially more crap with distance) and what's the point of using an array of emitters if you're just going to blast out sound?

StillTrying:

--- Quote from: Poe on July 03, 2019, 01:13:34 pm ---
If the emitter isn't tracking and just using phased array focusing, then the LED pattern should completely disappear as the turret moves away.
--- End quote ---

It looks like video and graphic clips are just pasted together into one video, I don't think that turret TX is lighting those LEDs.
They've just randomly stuck a battery charging graphic on anything that moves, or doesn't move. :horse:

PaulReynolds:

--- Quote from: jonovid on June 26, 2019, 02:33:48 pm ---is been blasted by KW's of ultrasound all day dangerous?

--- End quote ---

The simplest answer is - nobody knows for sure, but there are enough data points to be concerned. It doesn't exist naturally, and there's not been any equipment over the last century that consistently outputs 140dB+ in the 40 to 100 kHz range without far worse effects in the audible range swamping it, or consistent studies to isolate that effect. There are studies that show we should be concerned both with long term effects, as well as more short term ones - long term hearing damage, sub harmonic generation, heating etc - but nothing definitively proven. It would also be unethical to run those experiments on people, so basically we're in the early stages of a mass experiment in this regard where the public are the test subjects. In a sane world, this wouldn't be allowed to be tested in this manner until proven safe, rather than the situation we have now which is "prove it's dangerous and then we'll stop", where those tests are illegal as well as unethical - an unattainable burden of proof

uBeam claim to have run lots of independent 3rd party tests that prove it's safe. Except they won't release those test results or say who the third parties are. I call bullshit on this. There's enough data out there that makes it very suspicious. That they keep claiming that "99% of energy bounces off the skin" is telling, as it's not the skin that's the problem, it's the hair on it that causes the problem (loss in hair causes heating, burns, and in small animals death at high enough levels).

I put together a list of information on this topic if you want to study further:

https://liesandstartuppr.blogspot.com/2019/01/ultrasound-in-air-safety-and-regulations.html

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