Author Topic: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?  (Read 2028 times)

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Offline SMB784

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #25 on: June 07, 2018, 05:53:01 pm »
This is hard to believe, both because the receiver looks like a simple solar cell

And that's another thing I forgot to mention in the video.
The patent mentions retroreflectors, and a previous prototype does that, but I'm not sure if the latest one does.
Their entire concept from day one was doing away with one mirror in the traditional laser cavity and using the retroreflector in the receiver to complete the cavity. i.e. it becomes an "external cavity" laser.
The idea is that if you break that external cavity beam, the laser effectively automagically shuts of instantly.
Scatter is still a major danger though.

Howdy Dave,

Your point about safety is in fact the most salient reason why this device cannot ever come to market, and likely doesn't actually exist.

I did a couple of back of the envelope calculations (that I will show tomorrow) that demonstrate that this thing would far outshine the sun if it hit any surface, and it wouldn't even be visible due to the NIR nature of the laser, so you would have no idea that you were going blind until it had already happened.

I wouldn't even be able to get safety clearance for this device in my laser lab; there is no way this device is FDA cleared for anything other than some R&D environment, and if the video is actually a real prototype at the stated specifications, the poor man in the video is now almost certainly blind.
« Last Edit: June 07, 2018, 05:56:38 pm by SMB784 »
"Anything will lase if you hit it hard enough."

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Offline G7PSK

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #26 on: June 07, 2018, 06:48:05 pm »
A 5 KW laser will cut through 25mm of steel (https://www.msslasers.com/used-lasers-for-sale/trumpf-5030-fiber ) so what damage will 20 watts do, it should be able to cut tin foil.
 

Offline EEVblog

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #27 on: June 07, 2018, 07:05:13 pm »
I've watched the linus vid again closely, I think there's a chance it's faked!

I greatly doubt it's fake, but it's almost certainly a highly engineered demo, likely one that needs some potential massaging to get working.
In fact it's not new, they have had the speaker and train demos for a long time now.

 

Offline janekm

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #28 on: June 07, 2018, 07:26:33 pm »
This blog which is linked as the official blog from the wi-charge site has a curious article today: https://chargeguy.blogspot.com/2018/06/is-line-of-sight-required-for-wireless.html

Suggesting that using reflections off random surfaces in the environment to overcome obstructions would be practical for the wi-charge solutions seems a little odd (though it would kind of mesh with the free-space laser concept, but hard to imagine that would work bounced off of other surfaces, not to mention the issue of scattering...)
 

Offline apis

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #29 on: June 07, 2018, 08:25:58 pm »
What if you put a small reflective object, like a needle, onto the receiver while it is charging. Instant blindness (from the reflections)?
 

Offline madires

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #30 on: June 07, 2018, 09:00:47 pm »
Using reflection would decrease the efficiency dramatically more. The surfaces of your furniture and walls have different reflection factors (from absorbing up to full reflection) and the reflected IR will be spread even more, i.e. less power per area. Some people think that they can ignore basic physics. :palm:
 

Offline Psi

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #31 on: June 08, 2018, 06:50:13 pm »
I've watched the linus vid again closely, I think there's a chance it's faked!

I greatly doubt it's fake, but it's almost certainly a highly engineered demo, likely one that needs some potential massaging to get working.

Yeah, i made a thread recently showing just how efficient you can get precious metal brushed DC motors.
12VDC motors that have enough starting torque from 65mV input.
http://www.eevblog.com/forum/chat/post-a-guess-on-the-min-starting-voltage-for-this-brushed-dc-motor/msg1560541/#msg1560541

I'm sure you could make a train using those kind of motors combined with really high quality ball bearings on the wheels.
You'd end up with a train that moves from a really small amount of energy, compared to a normal toy train, but at ridiculous cost.

« Last Edit: June 08, 2018, 06:54:07 pm by Psi »
Greek letter 'Psi' (not Pounds per Square Inch)
 

Offline lem_ix

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #32 on: June 08, 2018, 09:07:25 pm »
Power and lasers, what could possibly go wrong  |O Blinding people aside, I wonder if this tech will end up in a completely different field.
 

Offline fatboy77

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #33 on: June 09, 2018, 12:08:06 pm »
Yeah i find the trains in all videos i saw are too stable considering they have no batteries inside...
The testers should show us IR glasses view or PIR or something :)
Keep up the good job!
 

Offline NiHaoMike

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Re: EEVblog #1092 - Wi-Charge IR Wireless Charging - Fact or Fiction?
« Reply #34 on: June 09, 2018, 01:50:35 pm »
What if the light source is not a laser but a conventional light source like LEDs or even incandescent bulbs? 250W heat lamps are easy to get off the shelf and are relatively safe to use.
Cryptocurrency has taught me to love math and at the same time be baffled by it.

Cryptocurrency lesson 0: Altcoins and Bitcoin are not the same thing.
 


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