A New Age of Power | Hacker News Reader

A New Age of Power

ubeam.com

27 pointsapsec11210 comments

If this thing really works a lot of people on HN will be forced to eat crow.

These are the same guys who, last year, had a little ultrasonic power transmission link made from old camera ranging sensors.[1] They were very vague about efficiency and range then, and they're very vague about efficiency and range now.

The first picture shows the Earth from space. Ultrasonics don't work in vacuum, guys.

Covered on YCombinator last year.[2]

[1] http://www.engadget.com/2014/08/07/ubeam-wireless-charger-ul... [2] https://news.ycombinator.com/item?id=8542091

They link to this, and leave out the latter part:

A Study on the Effectiveness of Ultrasonic Sound Emitters [in Controlling Bat Populations]

They're practically parodying themselves at this point.

I'm guessing ubeam is also the subject of this wsj article, though I can't get past the loginwall: http://www.wsj.com/articles/soon-power-will-be-delivered-to-...

I believe the CEO Meredith Perry was on TED or some such preaching about ignoring scientists and techies when they say something is impossible, just believe, keep pushing, and it'll all come good.

Maybe this is the next unicorn.

"The most recent paper to investigate the safety of ultrasound was just published [...] Of note is that this study used energy levels to tissue that were orders of magnitude higher than levels that uBeam’s system uses."

The abstract at http://www.sciencedirect.com/science/article/pii/S0041624X15...:

"Demonstrated in vitro, 0.6 W of transcutaneous ultrasound power transfer to an implant.[...] with an average RF input to electrical charging efficiency of 20%"

So, at best, 3W is "orders of magnitude higher than levels that uBeam’s system uses". That will charge your remote, but not your phone.

To distribute sound over long distances 'wirelessly' you need to make it loud. That typically means cranking up the power. And ultrasound can be harmful at high power [1].

[1]

"Occupational exposure to ultrasound in excess of 120 dB may lead to hearing loss. Exposure in excess of 155 dB may produce heating effects that are harmful to the human body..."

https://en.wikipedia.org/wiki/Ultrasound

uBeam's name is a killing word.

Human ears can't hear ultrasound. What about other animals[1] on this planet? [1]https://en.wikipedia.org/wiki/Ultrasound#Animals

They noted dogs in the write-up so I assume they are using extremely high frequencies far beyond what animals can hear.

Any time someone starts off with a review of when scientists were wrong, you know snake oil will follow. In the section on bats they specifically mention how quickly ultrasound power drops off, but never discuss how that same bit of physics affects their main value proposition (hint: a lot). The irony of them going on to say "it's terrible that companies sell these devices because they're ripping people off" is pretty thick.

Reply on news.ycombinator.com