AURA: The first ever, wirelessly powered Christmas lights

Aura creates a field of wireless electricity around your Christmas tree. This enables the first ever, wirelessly powered ornaments and with it, infinite possibilities.



Kickstarter:
https://www.kickstarter.com/projects/1034423012/aura-the-first-ever-wirelessly-powered-christmas-l

Aura Website:
http://www.poweredbyaura.com/

Now there is a really bad idea! I'll stop short of calling it a scam, but that's the first word that came to mind. I think there are going to be a lot of very unhappy kickstarters out there.

...Tiger

@Tiger - Why do you feel this is a bad idea? I thought it was kind of cool, although expensive and even though they are LED this might use more power than a modern string of LED bulbs.

Doesn't it look like these are working on the same principle of all the new wireless mobile phone chargers on the market? I am not familiar with the inner workings of these wireless chargers so can't say one way or another.

I think it's a bad idea, because it isn't going to work well at all. Yes it does work essentially the same as the other wireless chargers and suffers from the same limitations. If you raised your phone an inch above the charging pad, it would probably take a week to charge. The problem is that you can't transmit the power very far at all and you have to generate a lot more power than you will ever transfer. Do the math. The power falls off with the square of the distance. For example: The power available at one inch is only a quarter of what was available at a half inch. At two inches it's only a sixteenth of the power and so on. How much power do you think it's going to take at the bottom to have anything useful at the top of the tree? Also, to work at all in this kind of application, the frequency is going to need to be pretty high so the coils can resonate, rather than just inductively couple. It's simply wouldn't to be safe to generate enough power at the source, to get anything reasonable at the load. I think this is one of these things that looks good in a simple demo and then falls apart in a real world application. You hear a lot about "transmitting" power, but you'll notice nobody is really doing it in a meaningful way.

...Tiger

Good point. Wouldn't that imply that the bulbs would be dimmer the further they are away from the ring? Maybe that kid in the second video is hanging the bulb directly on the power ring.

Well... I would assume they have voltage regulation to equalize the brightness. For sure the available power is going to drop off dramatically as you move away from the coil. Also, the addition of more lights (loads) will reduce the available power, regardless of distance. Just not a great plan in my estimation.

...Tiger

I was re-reading the kickstarter page and they claim that one power ring can power 100 of their wireless bulb ornaments.
Regarding the distance they seem to have two diameter sizes of the power ring, 30" and 42". They show that for large trees you should mount the power ring in the center of the tree. See diagram:



This jives with what you are saying about the distance of the bulb/ornament from the power ring. What I couldn't find is any mention of dimming of the bulbs as they are placed on the tree further from the power ring.

Do you think the ring gets warm or hot?

I saw that on the kickstarter page when you first posted. It was after I went there that I got so critical. There has to be a voltage regulator in the bulb. If there wasn't, they would blow out at the bottom and who knows what at the top. I wouldn't expect anything to dim until you started running out of power and you couldn't meet the input requirement of the regulator. That could be from distance or loading. I'm betting these things are not very bright (yes I watched the video). There just isn't going to be that much power available.

...Tiger

John - Auro just made it to Hack-A-Day. Check it out. They guy dropped the real ball when he got focused on the glass ball, but it's still a good read. It's a new posting so the comments at the bottom are limited, but give it a couple days and there will be a pile of them. I must say that I was cleverly distracted and missed the empty ball.

http://hackaday.com/2014/12/01/christmas-lights-and-ships-in-a-bottle/

...Tiger

Good post! They raise the claims you made. They do get hung up on the PCB being inside the glass ornament though. I remember seeing plenty of glass ornaments with things inside as a kid. I don't know how they do it but that seems to be more realistic than the electronic claims.
Good eyes on behalf of the poster that the video with the kid hanging a empty ornament and the light coming from the wrong side of the tree. I'd like to hear what the Aura folks have to say about that.

Just went to the HAD posting again to see what the comments were now. Lots more comments, but most of them are as stupid and the ornaments were. As for the packaging, I'm sure you could find something that would work, but if the lights don't come on, packaging doesn't seem very important. Think I'm done with this one.

...Tiger

Kickstarter is supposed to police fraudulent projects. I wonder how that all works. Can the project folks get the money and run? I guess we'll see how this one progresses, if at all.