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Wi-Fi signals enable gesture recognition throughout entire home

washington.edu

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Re: Wi-Fi signals enable gesture recognition throughout entire home

#61

Post by OldSchool »

I've often wondered is to what extent existing RF noise as "illumination" could be leveraged to effect some kind of passively acquired representation of objects. Resolution would of course be limited by wavelength but improved if the antenna array was physically moving in a describable manner. We had useful SAR during the cold war and orders of magnitude more compute power today. If you know of more efforts along these lines from hacker to research level, please post a link.

Re: Wi-Fi signals enable gesture recognition throughout entire home

#63

Post by maxerickson »

dm2 wrote: post #46
moron4hire wrote: post #32

Earlier quoted context omitted.

I should have said "Home automation for the masses." I know, I worked at a startup in the space. The people who are capable of spending the money will spend the extra necessary to get someone to install it for them. The people who would install it themselves can't afford even the basic systems, as you need quite a few devices before the things get useful. The most profitable use we ever found for it was to provide li…

For under $1,000 you can easily build a significant home automation system. http://www.amazon.com/b?ie=UTF8&node=2315509011

One definition of cheap would be something like $0.10 for self contained electronics in a light bulb. Then the installation is practically an accident.

(I think home automation sounds like a neat idea, but I always end up trying to figure out $10 of value that it would provide...)

Re: Wi-Fi signals enable gesture recognition throughout entire home

#64

Post by aidenn0 »

stephengillie wrote: post #55
ChuckMcM wrote: post #48

Ok DD-WRT folks, get to it :-) More seriously though, this is a pretty cool thing, using your motion which is blocking wireless signals to detect motion. In hindsight its kind of obvious since people are 'giant waterbags of attenuation' as my RF buddy calls them. This also means you can probably add something of a burglar alarm/motion sensor system to these things, and if you were careful you might be able to see the…

We can track people, cool! And probably kids too! What about dogs and cats? Rats, mice, and cockroaches? What's the range on this technology, and what happens if we move the router around with us? Maybe we take it to a new building and plug it in there? Or maybe we can use the wifi modules on phones to do this also? It sounds like a great scanning device. And how long before we can also see huge chunks of metal or st…

6cm is the wavelength at 5GHz and most sensing devices have issues with sub-wavelength objects. If you're paranoid you can hang a bunch of strips of aluminum foil that are 3cm long all around your house, which could confuse the sensor. (see http://en.wikipedia.org/wiki/Chaff_(countermeasure))

Re: Wi-Fi signals enable gesture recognition throughout entire home

#66

Post by nooneelse »

Someone wrote: post #33
hammock wrote: post #31

Earlier quoted context omitted.

Your pet turns the shower on? That sounds like a real problem

I think he refers to having a system that, using this approach, turns on his shower when he enters it. If this cannot distinguish humans from cats, it would turn on the shower when a cat entered it. I think that's a bad example. The typical cat would soon learn not to enter the shower.

If the system has enough lag, clever cats might dart in and out before the shower sprayed for a brief bit, so as to get some fresh water (which they like more).

Re: Wi-Fi signals enable gesture recognition throughout entire home

#67

Post by theoj »

aidenn0 wrote: post #64
stephengillie wrote: post #55

Earlier quoted context omitted.

We can track people, cool! And probably kids too! What about dogs and cats? Rats, mice, and cockroaches? What's the range on this technology, and what happens if we move the router around with us? Maybe we take it to a new building and plug it in there? Or maybe we can use the wifi modules on phones to do this also? It sounds like a great scanning device. And how long before we can also see huge chunks of metal or st…

6cm is the wavelength at 5GHz and most sensing devices have issues with sub-wavelength objects. If you're paranoid you can hang a bunch of strips of aluminum foil that are 3cm long all around your house, which could confuse the sensor. (see http://en.wikipedia.org/wiki/Chaff_(countermeasure) )

Work is underway on 60Ghz Wifi, which has wavelengths of only a few millimeters.

http://www.pcworld.com/article/2030041/meet-60ghz-wi-fi-the-...

In a few years we could have tri-band routers covering 2.4Ghz, 5Ghz and 60Ghz. Correlating the info from all these frequencies should provide a much better picture.

Re: Wi-Fi signals enable gesture recognition throughout entire home

#68

Post by TeMPOraL »

maxerickson wrote: post #63
dm2 wrote: post #46

Earlier quoted context omitted.

For under $1,000 you can easily build a significant home automation system. http://www.amazon.com/b?ie=UTF8&node=2315509011

One definition of cheap would be something like $0.10 for self contained electronics in a light bulb. Then the installation is practically an accident. (I think home automation sounds like a neat idea, but I always end up trying to figure out $10 of value that it would provide...)

> $0.10 for self contained electronics in a light bulb

I guess we'll get there at some point, but I'd rather prefer a $.10 for a wall-socket adapter with electronics. Much more versatile. I'd buy truckload of these and connect all stuff through it. As for lights, why not $.10 light bulb slot adapter?

> I think home automation sounds like a neat idea, but I always end up trying to figure out $10 of value that it would provide...

Fun and hackability, obviously :).

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