Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror
×
Hardware Hacking Wireless Networking Build

Using RFID Tags Around the House? 254

Attacked-by-gremlins writes "I have a larger family and various items in the house (some tools, some pieces of clothing) 'travel' unexpectedly. We joke about gremlins doing that, but it's tiring never to be sure that I'll find an object where I left it two days ago. For the sheer hacking fun of it, I'm thinking of sticking RFID tags on some and trying to triangulate a position with several tranceivers placed in the house. Has anyone have any suggestions for this amateur 'Google Home'? Thanks."
This discussion has been archived. No new comments can be posted.

Using RFID Tags Around the House?

Comments Filter:
  • by bsharma ( 577257 ) on Tuesday May 20, 2008 @12:45PM (#23477724)
    Try UHF(ISM band 903-928 MHz) RFID Readers; they have better range than HF readers (13 MHz). Intel sells a single chip (R1000) demo kit you can take and hack. You may have difficulty with large metallic objects due to reflection. Also, stuff with high water (H2O) content may absorb too much power to reflect back. With UHF, you may expect 5+ meters (20 feet) under ideal condition. The tags may be expensive in small quantity. Try to "borrow" from a larger lot. Obviously, you have to get UHF tags for UHF readers; I am not aware of multimode readers/tags.
  • Re:Why Not? (Score:1, Interesting)

    by Anonymous Coward on Tuesday May 20, 2008 @12:46PM (#23477770)

    Has anyone have any suggestions for this amateur 'Google Home'?

    Yeah - make the interface family-friendly (it can be as simple as an alphabetical list that's easy to pull up quickly on any house screen) and take notes about how it's used and how it changes with how family interacts with "stuff" and each other. As the thread parent suggests, this is a bit of a shift, like individuals being always contactable by personal cell phone was, so there's new things to be learned. Not necessarily bad or good, but different. Making the interface daily-appliance-easy is important to keep the interaction from being coloured by tech novelty.

    Also, WHO ARE YOU? "Attacked-by-gremlins" is not a /. login. Are you a geek with a tech and code background? Are you more of an ordinary guy/gal who wants to ask geeks to figure it out for you? Are you some quasi-professional blogger or journalist who wants to write this up, and maybe even profit from some patenting? WHO YOU ARE really slants your request - so what's the deal?
  • by xant ( 99438 ) on Tuesday May 20, 2008 @01:00PM (#23478014) Homepage
    Our obsession with making everything small leads directly to this problem. Smaller things get lost more easily.

    They sell those giant-sized remote controls at Walgreens or your local random-crap-mart. Buy one, you'll never lose it again. It can't fall between the cushions of the couch because it's friggin huge. If the thing you don't want to lose doesn't come in giant-size, permanently attach it to something which is too large to lose but still portable. Gas stations have learned this lesson, that's why the bathroom key is attached to a huge plank.

    To make it even easier, paint it something bright and garish.
  • Why triangulate? (Score:3, Interesting)

    by MarkvW ( 1037596 ) on Tuesday May 20, 2008 @01:01PM (#23478038)
    Why not have a portable reader that you can carry around with you. When you enter the room, you can get a printout of all the stuff in the room. If the printout does not correspond with your organizational directives--that's what kids are for!
  • by Anonymous Coward on Tuesday May 20, 2008 @01:05PM (#23478132)
    Forget your house, try scanning your garage to see what RFIDs the feds see when you drive over wires buried in certain roads.

    TOP SECRET FACT:Most modern cars have tracking transponders ALREADY!

    Spy transmission chips embedded in tires that can be read REMOTELY while driving.

    Yup. My brother works on them (since 2001).

    The us gov T.R.E.A.D. act (which passed) made it illegal to sell new passenger cars lacking untamperable RFID in the tires allowing efficient scanning of moving cars.

    Your tires have a passive coil with 64 to 128 bit serial number emitter in them! (AIAG B-11 ADC v3.0) . A particular frequency energizes it enough so that a receiver can read its little ROM. A ROM which in essence is your GUID for your TIRE. Multiple tires do not confuse the readers. Its almost identical to all "FastPass" "SpeedPass" technologies you see on gasoline keychain dongles and commuter windshield sticker-chips. The US gov has secretly started using these chips to track people.

    Its kind of like FBI "Taggants" in fertilizer and "Taggants" in Gasoline and Bullets, and Blackpowder. But these car tire transponder Ids are meant to actively track and trace movement of your car.

    Taggant chemical research papers :
    Â http://www.wws.princeton.edu/cgi-bin/byteserv.prl/~ota/disk3/1980/8017/801705.PDF
    (remove spaces in url from slashcode if needed)

    The chips in your tires are for forensic "after the fact" database tracking, from databases collected on highway choke points, It can be done in real time too though.

    I am not making this up. Melt down a high end Firestone, or Bridgestone tire and go through the bits near the rim (sometimes at base of tread) and you will locate the transmitter (similar to 'grain of rice' pet ids and Mobile SpeedPass, but not as high tech as the tollbooth based units). Sokymat LOGI 160, and Sokymat LOGI 120 transponder buttons are just SOME of the transponders found in modern high end car tires. The AIAG B-11 Tire tracking standard is now implemented for all 3rd party transponder manufactures [covered below].

    It is allegedly for QA and to prevent fraud and "car theft", but the US Customs service uses it in Canada to detect people who swap license plates on cars when doing a transport of contraband on a mule vehicle that normally has not logged enough hours across the border. The customs service and FBI do not yet talk about this, and are starting using it soon.

    A secret initiative exists to track all funnel-points on interstates and US borders for car tire ID transponders (RFID chips embedded in the tire).
    The governement can then either look back in databases to see wheere and when your car drove, and OCR liscense plates at tool or Customs can
    build the database up even better without the feds needing to visit your home to get your RFID GUIDs.

    More sinister, it is near impossible to buy tires without the vendor in the USA filling out federal paperwork of what VIN the recipient car is!

    Photos of tracking chips before molded deep into tires! :
    http://www.sokymat.com/index.php?id=94

    PLEASE LOOK AT THAT LINK : Its the same shocking tire material I have been trying to tell people about since the spring of 2001 on slashdot.

    a controversial dead older link was at http://www.sokymat.com/sp/applications/tireid.html

    (slashdot ruins links, so you will have to remove the ASCII space it insertes usually into any of my urls to get to the shocking info and photos on the enbedded LOGI 160 chips that the us gov scans when you cross mexican and canadian borders.)

    You never heard of it either because nobody moderates on slashdot anymore and this is probably +0 still. It has also never appeared in print before and is very secret.

    Californias Fastpass is being upgraded to scan ALL responding car tires in future years upcoming. I-75 may get them next in rural funnel points in Ohio.

    The photo of the secret high speed overpass prototype WAS at :
    http://www.tadiran-telematic
  • by Eristone ( 146133 ) * <slashdot@casaichiban.com> on Tuesday May 20, 2008 @01:08PM (#23478206) Homepage
    My current employer (i.e. disclaimer - I work for 'em) has stuff [wherenet.com] that does this -- it's definitely not cheap though. Uses active RFID tags and wireless access points to do the triangulation stuff.
  • Re:Why Not? (Score:2, Interesting)

    by uglydog ( 944971 ) on Tuesday May 20, 2008 @01:21PM (#23478454)
    zappepcs mentioned corporal punishment as a solution. Misbehaving children seems to be a western phenomenon, at least according to the movie East is East [imdb.com]. so perhaps a non-technical solution IS in order.

    errr...no, i don't have kids. but i'll bloody well be sure to beat them soundly on a regular basis. for the sake of the future.
  • monitor doorways (Score:2, Interesting)

    by mathimus1863 ( 1120437 ) on Tuesday May 20, 2008 @01:22PM (#23478470)
    So it's too expensive to buy the readers to do triangulation. But you could buy the cheap readers and put them on doorways to trace things as they pass by. Then you can track what room an object was last seen in. That is probably sufficient for your purposes.
  • Re:Range (Score:5, Interesting)

    by isleshocky77 ( 962627 ) on Tuesday May 20, 2008 @01:54PM (#23479080)
    I would have to agree. I just had to do a project for a senior class on tracking people on RFID. It's so bad that decided to use another technology. RFID is just too expensive for anything over centimeter ranges. We ended up going with Zigbee devices from Texas Instruments. If you want to read about our setup it's all here. http://peopletrackerinc.com/ [peopletrackerinc.com] Their really cheap and small, accurate up to 1-2 meters with about 100 yard range. It uses something similar to 802.11 for wireless transmission. It's extremely cool if you want to look into. We have the entire setup up and running to track people within a building.
  • Anonymous Coward (Score:1, Interesting)

    by Anonymous Coward on Tuesday May 20, 2008 @02:23PM (#23479656)
    This is not so easy to do because of all the interference from walls, appliances, doors, people, etc. Indoor location detection is actually an active research topic.
  • Re:$$$ budget? (Score:3, Interesting)

    by Red Flayer ( 890720 ) on Tuesday May 20, 2008 @02:40PM (#23479952) Journal

    The ones we use that are able to triangulate (2-D with two readers, 3-D with 3 readers)
    Huh? How does one triangulate in n dimensions without n+1 receivers?

    For two dimensions, I understand it as follows... place one reader in the plane of the objects, and one outside the plane. The circle you get from combining the data from the two readers will intersect the plane in two points, so at best you can get a set of two possible locations for the object. If the readers are sufficiently accurate (and precise!), and the readers are placed close to each other, the circle can be small enough that the two points of intersection with the plane are within your margin of error... note that the margin of error will at any rate have its upper limit as the distance between the readers. I'd assume that cost goes up as accuracy does.

    But how does one triangulate in three dimensions with only three receivers? At best you can get a set of possible locations... any mathematicians care to walk me through this one, since I seem to be geometrically challenged right now? Or is it just a matter, as with two dimensions, of highly accurate and precise readers placed very close to eachother?
  • Why not screw triangulation and just install enough readers around the house to locate it by which reader response?
  • by choseph ( 1024971 ) on Tuesday May 20, 2008 @03:16PM (#23480488)
    Maybe buy a a bunch of cheaper receivers and put them on every door jamb in the house. At least then you'll have a "last seen in this room" style locator.
  • Re:hah (Score:3, Interesting)

    by tknd ( 979052 ) on Tuesday May 20, 2008 @04:17PM (#23481600)

    A little off-topic but one thing that annoys the hell out of me is maintaining food in the fridge. Just how far is the range on a passive RFID?

    For example it would be really cool if things like mayonnaise jars came with RFIDs and your refrigerator had an RFID reader + internet connection. Then you could run a database on the fridge and when you were away from home you could figure out hold old the mayonnaise is without having to open the fridge. In fact we could go one step further and have the fridge email you when the mayonnaise gets too old or automatically add it your shopping list. So the next time you hit the store you'll have a preprepared list of items to buy without even having to think!

  • by nospam007 ( 722110 ) on Tuesday May 20, 2008 @05:59PM (#23483334)
    packrat infestation.

    http://en.wikipedia.org/wiki/Wood_rat [wikipedia.org]

    Pack rats are prevalent in the deserts and highlands of western United States and northern Mexico. They also occur in parts of the eastern United States and Western Canada. Pack rats are a little smaller than a typical rat and have long, sometimes bushy tails.

    Pack rats build complex nests of twigs, called "middens", often incorporating cactus. Nests are often built in small caves, but frequently also in the attics and walls of houses. Some Neotoma species, such as the White-throated Woodrat (N. albigula), use the base of a prickly pear or cholla cactus as the site for their home, utilizing the cactus' spines for protection from predators. Others, like the Desert Woodrat (N. lepida) will appropriate the burrows of ground squirrels or kangaroo rats and fortify the entrance with sticks and bits of spiny cactus stems fallen from Jumping and Teddy-bear Chollas.

    In houses, pack rats are active nocturnally, searching for food and nest material. A peculiar characteristic is that if they find something they want, they will drop what they are currently carrying, for example a piece of cactus, and "trade" it for the new item. They are particularly fond of shiny objects, leading to tales of rats swapping jewelry for a stone.

All the simple programs have been written.

Working...