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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."
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Using RFID Tags Around the House?

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  • Why Not? (Score:4, Funny)

    by FurtiveGlancer ( 1274746 ) <> on Tuesday May 20, 2008 @12:21PM (#23477242) Journal
    Beats the heck out of everyone learning to be considerate of each others' property. What benefit would that have in real life? ~
    • Re: (Score:3, Insightful)

      by Romancer ( 19668 )
      "Beats the heck out of everyone learning to be considerate of each others' property. What benefit would that have in real life? ~"

      Seriously, moderated flaimbait? Now you've got to be kidding. Funny or insightful at least, come on meta mods, please catch this one if it's not fixed now.

      Mod me down for off topic if you must but I'm actually willing to take a hit if it gets this parent back into the +
      The parent is a valid point about the topic.
    • Re:Why Not? (Score:5, Insightful)

      by ciaohound ( 118419 ) on Tuesday May 20, 2008 @12:42PM (#23477662)
      You obviously don't have young children, or if you do, turn in your geek card now for dismissing appropriate technology for a problem that has vexed geek dads for generations. My dad attached his scissors to his desk with a chain. We learned to subvert that by using his letter opener to pry open the link. Voila, scissors walk off and disapper. With kids of my own, I find that anything of value must be physically secured, with lock and key. It is irritating when they pull out the entire set of pots, pans, and storage containers and build a barricade in the kitchen, but that's what kids do, and it is kind of cute, after all, and it's probably just a phase that they go through. But no matter what, the door to my basement office stays locked.
      • Re:Why Not? (Score:4, Funny)

        by lisaparratt ( 752068 ) on Tuesday May 20, 2008 @01:01PM (#23478036)
        Yeah, can't have the kids finding the gimp locked in the "office".
        • Re: (Score:3, Funny)

          by RanCossack ( 1138431 )
          I agree, as far as introducing kids to open source software goes, the Gimp is probably a bad choice. Something simpler -- maybe tux paint -- would be best.
      • Re: (Score:2, Interesting)

        by uglydog ( 944971 )
        zappepcs mentioned corporal punishment as a solution. Misbehaving children seems to be a western phenomenon, at least according to the movie East is East []. so perhaps a non-technical solution IS in order., 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.
        • Re: (Score:3, Insightful)

          by hoggoth ( 414195 )
          > Misbehaving children seems to be a western phenomenon

          That's because Western adults value people who can think for themselves and challenge authority.
      • I was going to reply to the guy about the hammers. I have 6 or 7 hammers in my house. Somewhere. Sometimes I leave them in one of two places (garage or back porch), but other people move them more frequently than I do, and they never land where I'd expect.

        I found one in the bedroom. The wife was hanging something up. The rest are AWOL. I hope to see them again someday.

        I think he'll run into some serious problems with RFID's. First, the sensor broadcast all the time, wh
    • I think it would be useful, even if I lived alone. Heck it would probably be more useful.

      It has nothing to do with consideration, and everything to do with something simply being set down somewhere and you not remembering where - even if that place is where it's "supposed" to be.

      I thought Woz was already working on some kind of home location tag system though that sounded more practical.
  • Range (Score:4, Informative)

    by Cyner ( 267154 ) on Tuesday May 20, 2008 @12:21PM (#23477254) Homepage
    There's some equipment out there with decent range, but it's usually quite expensive. My $50 do-it-all tranciever has a range of about 6 inches. With the lower frequency tags you get better range, but still I don't think I've seen trancievers with anywhere-in-the-house type range.
    • OK, what would it take to triangulate location within a 6" on a side cube? To within millimeter accuracy? We are currently using a multi-million dollar x-ray scanner to do this at low doses, and if this can be done for a few thousands of dollars, that would be big deal.
    • Re: (Score:3, Funny)

      Besides, if there are in fact gremlins moving around your stuff, you're probably better off not knowing.
    • 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. [] 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.
  • by barc0001 ( 173002 ) on Tuesday May 20, 2008 @12:21PM (#23477258)
    Really. Most sub $100 readers have a range that can be measured in millimeters. To get something with about 3' or 4' of range for a single reader will cost four figures. I've done some fairly extensive testing with these readers, and it is possible to boost the range by adding external antennas (for more money). So I guess what I am saying is that what you are planning on doing is technically possible, but is not feasible for most peoples' "tinkering" budgets.
    • by mcmonkey ( 96054 ) on Tuesday May 20, 2008 @05:30PM (#23482880) Homepage
      Don't be put off by the nay-sayers. It's actually not too hard and not too expensive.

      I've been playing with RFID for about 5 years, and it's great for remote controls, tape measures, and other easy to misplace items.

      I also managed to get it to work with the Collectorz [] software, so I can 'check out' a book or movie.

      The hand-held reader I have is powerful enough so that I can stand in middle of a small room (approx. 10' x 10') and get a reading if the item I'm looking for is in the room. Handy for finding stuff. It was around $200, and that was a year ago.

      I'd post the make and model number of the reader, but I haven't been able to find it for a couple days. I probably should have tagged it.

  • $$$ budget? (Score:3, Informative)

    by gnick ( 1211984 ) on Tuesday May 20, 2008 @12:22PM (#23477280) Homepage
    I don't know what your budget is like, but the readers can be pricey. The ones we use that are able to triangulate (2-D with two readers, 3-D with 3 readers) ran about $4k apiece. But, they would easily cover a standard sized home.

    Of course, we had different needs than you, so there are probably considerably cheaper alternatives.
    • Re:$$$ budget? (Score:4, Insightful)

      by agurk ( 193950 ) on Tuesday May 20, 2008 @12:31PM (#23477454)
      Depending on the size of the home he might consider using readers which only covers every door. So the system atleast keeps track of which room contains said item.

      I do not know if this would be cheaper, just a thought.
      • Re: (Score:3, Insightful)

        by shogun ( 657 )
        Assuming of course noone just threw the item in question out the window.
    • Re: (Score:3, Interesting)

      by Red Flayer ( 890720 )

      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!)

      • by gnick ( 1211984 )

        Huh? How does one triangulate in n dimensions without n+1 receivers?

        Your logic seems solid enough to me. We aren't using the triangulation feature, so I probably remembered incorrectly and posted without thinking through. If I'm picturing things right:
        1 transceiver should be able to resolve location to a spherical surface. (Or a circle if you assume it's on the ground.)
        2 transceivers should get it down to a circle. (Or two points on the ground.)
        3 should give you a choice of 2 possible points. (Or 1 on the ground.)
        4 should find the tag in 3-D space.
        This is all assuming

  • by MessyBlob ( 1191033 ) on Tuesday May 20, 2008 @12:22PM (#23477290)
    Now, where dd I put that RFID scanner?
  • I've had the same thought. From TV remotes to your spectacles, there are lot of things that bear some tracking. No reason why it can't be a commercial product.
    • If the remote goes missing, the cable box goes back to the provider. I have no problem with that. When the kids want to pay for cable tv... meh, let them.
  • Buy two hammers separately. Make sure they are identical. Make sure you also have two receipts.

    Next time someone misplaces your stuff, use one hammer to break their hand. If the skin breaks and blood gets on the hammer, throw it in your neighbor's yard and find a way to plant the receipt over there.

    When the police come to find you, explain that you found your spouse, kid, dog, whatever in a crazed state with broken fingers. They must be hallucinating because they are blaming you. Hey, look at that! Maybe your neighbor just went inside, and, oh my god, there's a bloody hammer right next to his birdbath! Well, case closed, officer.

    You'll never have anything misplaced again.
  • I used products from a company called XMARK at my previous job. They make locater tags and equipment. It works well, but even being in that business for the last 5 years... I don't remember any company selling residential equipment.


    Maybe they (or their competitors) have a smaller unit that would work.

  • Have a lot of money available. Tranceivers that can detect small tags in a house-sized area are very large and expensive. Further, you would need at least two, and probably three depending on the house.

    It would be less cost and trouble to just buy triplicates (or more) of everything you commonly misplace.
    • Would it be possible to use a weaker reader and use it like a metal detector?

      If you could just tag items based on where they belong then you could sweep through the house looking for items that should be in a particular place. I think the submitter would be satisfied with something that would just speed up searches for items rather than needing absolute positioning of all items in the house.
  • He was selling some device that could tag and find things in the home. It was more like car-key radios than RFID with a longer range.
  • I haven't looked yet, but I'm pretty sure there's got to be some products out there that you attach the speaker/receiver to and then a remote that makes it beep. I know that some cordless house phones have that ability in case you misplace the phone. I've often wanted to put something similar on my remotes/keys/wallet/shoes/etc. Then you can have fun running around the house trying to find the sound.
  • many readers stashed around the house and go by lats read locations.
    Getting a reader that can do a whole room will be many hundreds, if not thousands, of dollars.

  • Install a security camera in the friggin' hall. Then you'll see the "ghosts" moving your clothes and stuff around :)

    Then, install cheap notebooks (or perhaps mini-audio recorders) next to the doors, so the next time anyone needs something, at least they'll give you a message. "Hey Frank, I need to borrow your ipod".

    If that doesn't work, hire a family counselor to force you guys to START COMMUNICATING!!
  • Based on everything I have read (many Slashdot posts, rarely articles), the only person in your household who would implement a RFID tracking system for various objects would be your eldest son, granted that he has siblings. Also, there is a chance that your in-home child care provider would take interest in this. Why not ask them, and report back?
  • Garage Sale (Score:4, Insightful)

    by Setherghd ( 942294 ) on Tuesday May 20, 2008 @12:41PM (#23477650)
    Have a garage sale, and get rid of everything you don't need.

    If you're losing items in messy closets or bedrooms, then you probably need to clean up the clutter. That or you own way too many valuable possessions that may be stolen or permanently lost. Live simple.

    I live in a small, energy-efficient home. I own exactly what I need and no more. I have a computer, a desk, a chair, books, an acoustic guitar, a bike, and a couch. And that's about it.

    All of my cookware and utensils stay in the kitchen and never leave. Cleaning supplies stay in a closet. My toothbrush in the medicine cabinet.

    I never lose a thing. Ever.
    • by wampus ( 1932 ) on Tuesday May 20, 2008 @01:28PM (#23478588)
      Good for you, I'd offer you a cookie, but you apparently have no facility to eliminate waste from your body.
    • by pavon ( 30274 )
      All my belongings used to fit into a large duffel bag, and I would still loose things just as often. It is more about people not putting things back when they are done using them (or having a very loose definition of when they are done using them) then it is about clutter.
    • Re:Garage Sale (Score:4, Informative)

      by IpalindromeI ( 515070 ) * on Tuesday May 20, 2008 @01:52PM (#23479064) Journal
      You clearly do not have children. It's easy to find everything when you're the only one using it, and you make sure to put it back where it belongs after every use. Add a few more people into the mix, not so easy.
    • Re: (Score:2, Insightful)

      by icebrain ( 944107 )
      Good for you. But some of the rest of us have memory problems.

      I'll put something down for a minute to go answer the phone, or use the bathroom, and then completely forget what I was in the middle of doing. Or, I'll get up and forget to put the tool down, and then spend five minutes looking for what I have in my hand.

      Trying to organize things, find a place for them, and keep it that way literally gives me headaches. I'm not quite sure why.
    • and this is applicable to a family with children, how... exactly?

      It's not really that the *children* need toys, insomuch as the parents need toys for their children so said children don't cause the parents to explode.
    • by jeko ( 179919 ) on Tuesday May 20, 2008 @05:40PM (#23483034)
      Once upon a time, I too was single. When I put things down, they remained there until I picked them up again.

      Then I got married, and the sudden Alzheimer's onset began. Things... Things began to move. It began small, tv remotes, car keys and the like. Soon it extended out to clothing, kitchen appliances. And then things began to just -- I'M NOT CRAZY DAMMIT! STOP LOOKING AT ME LIKE THAT! -- things began to DISAPPEAR. Treasured old jeans, t-shirts I'd had since high school, important tax receipts from 1992, they all began to just go away with no explanation.

      Then the poltergeists came, and my wife insisted on calling them children. I fiercely hold my TV remote in my hand, knowing that if I loosen my grip on it it will fly across the room. Change on the desktop, shiny hand tools, anything that beeps, whistles or lights up, DVDs of any stripe, anything less than 60 lbs of dead weight can fly away in a heartbeat.

      But I'm safe now, here in my closet. I got my favorite Leatherman, my surefire flashlight, my solid brass Zippo lighter and MY TV REMOTE DAMMIT and I am NOT LETTING GO OF THEM! NOT LETTING GO!

      And I am not opening the door. They're MINE, YA HEAR ME? MINE!!!!!!

  • Last room entered (Score:4, Insightful)

    by SoundGuyNoise ( 864550 ) on Tuesday May 20, 2008 @12:42PM (#23477656) Homepage
    Instead of trying to triangulate a position, you might be able to put a receivers on doorways, and log to a network each RFID signal received. This way when you look up your hammer, you can tell which doorway it last passed.
  • ...are a true geek. I salute you.
  • 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 re
  • You can get either the $6500.00 each scanners or spend $13000 in the $50.00 scanners and put them all over the place.

    simple is a central PC and scanners at every doorway 4 per doorway should do it. to cover both sides and high/low carrying. then simply query the last doorway that tag 4855432 passed by, now you have what room it is in.

    This works great until someone get's wise and then carries it in the doorway blind spots or grabs things at random and makes doors detect the items then smuggle them past the s
    • simple is a central PC and scanners at every doorway 4 per doorway should do it. to cover both sides and high/low carrying. then simply query the last doorway that tag 4855432 passed by, now you have what room it is in. This is actually the way I would go (only one per doorway though). I think you could do it in a pretty cost effective way, too. Triangulation inside a house would be pretty difficult given range restrictions and all the different kinds of interference and reflection from various things in t
      • At least until they figure out how to break the system: have two pairs of shoes. One pair that you leave inside for all your legitimate house leaving. The second pair that they leave outside (hidden somewhere, maybe under the deck, etc) for sneaky purposes. Build a better mousetrap, and someone will build a better mouse.
  • hah (Score:3, Informative)

    by jjshoe ( 410772 ) on Tuesday May 20, 2008 @12:48PM (#23477810) Homepage
    It seems most people here don't seem to understand active rfid vs. passive rfid.


    pro - Tags are extremely small, readers are cheap, tags are cheap
    con - Range, non-existant


    pro - Range
    con - expensive tags, tags are large, tags are battery powered
    • Re: (Score:3, Interesting)

      by tknd ( 979052 )

      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 e

  • by pointbeing ( 701902 ) on Tuesday May 20, 2008 @12:58PM (#23477976)
    As others have mentioned the range for passive RFID detection is painfully short - to do what OP wants he needs active tags and readers.

    A passive RFID tag is powered by the reader - hence its short range. An active tag carries its own power supply - like the toll booth speedpass tags.

    Active tags run from about the size of a dime to about the size of a paperback book - in my job I deal with the paperback book-sized tags.
  • 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!
  • Microwave stuff I want to hide?
  • ...because, and I'm serious, when one thinks of Google, one thinks of an amoral to evil enabler of totalitarian Police States.
  • by CopaceticOpus ( 965603 ) on Tuesday May 20, 2008 @01:02PM (#23478060)
    For this to be really useful, I think you need an RFID tag on every item in the home. First, construct a new home with a single entry point (you can add emergency exits for fire safety.) The front entry room will contain a computer and an RFID tagging device. Every single object that comes through the door gets tagged, named, photographed, and described in the computer system before it is allowed into the house.

    It's a little work upfront, but think of the advantages. No time wasted organizing your possessions. No time wasted "tidying up." Nothing can ever be out of place, because nothing BELONGS anywhere. The mixing bowl might not be in the kitchen, but it's no trouble. Just search for it using any of the dozens of wall terminals installed around the house, and a series of flashing arrows will direct you right to your desired object.
  • by Anonymous Coward
    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 pas
  • it would be more cost efficient to buy 10 of each item you keep losing. I keep a hairbrush chained to the bathroom counter with one of those bank pen-chain things (double length), I was sick of every single brush ending up not in the bathroom where I try to brush my hair. I wanted to do the same with the remote for the TV (chained to the couch), but have not yet.

    As for tools, I buy cheap wrench sets whenever they are on sale, and I only break out the good wrenches after I have broken one of my cheapies.
  • by jnadke ( 907188 ) on Tuesday May 20, 2008 @01:12PM (#23478300)
    Whatever you do, *DON'T* put RFID tags on your socks.

    They're missing for a reason. If you find them, a paradoxical black hole will open up in your dryer and engulf the entire planet. Trust me, I've done the math.

    For the love of god... not the socks.
  • This sounds like the NASA joke of spending 1.5Million to write in space where as the USSR used a pencil. []

    The cheap solution is to purchase some of these cheap tags and attach them to the objects in question; [] [] []

    That last one is under $2US.
  • monitor doorways (Score:2, Interesting)

    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.
  • Homeseer (Score:3, Informative)

    by wpiman ( 739077 ) on Tuesday May 20, 2008 @01:26PM (#23478538)
    I use a product called Homeseer and alot of people are already doing this. There are two types of tags people are using, iAutomate tags and cheaperRFID tags. The iAutomate tags are more complex, and hence more expensive. I have the Cheaper RFID tags. I have one in our laptops bags-- if no laptops are present-- no wifi. I don't believe they do triangulation. The iAutomate ones do- but are far more expensive-- at least when I last looked.
  • by rueger ( 210566 ) on Tuesday May 20, 2008 @01:34PM (#23478702) Homepage
    "I'm thinking of sticking RFID tags on some and trying to triangulate a position with several tranceivers placed in the house. (Does) anyone have any suggestions(?)"

    When you have people over for a dinner party, turn off the speaker that says "PLEASE RETURN TO THE STORE!"
  • Sparkfun [] has a nice RFID reader for $35 and tags for $2.00. The only problem the RFID has a reading distance of 8 inches. A UHF system is in the thousands of $$.
  • A lot of funny comments, but I see a real need for small passive RFID tags. My father is getting on in years and he loses/misplaces small things. Like his glasses, which is a small problem. Like his hearing aids; family members are currently looking for a hearing aid that has been missing for over a week. And, like his false teeth, which he no longer has, because he/we cannot afford to continue replacing them after the first couple of times. I don't really need to identify the item uniquely, I just want a
  • Finally... (Score:2, Funny)

    by arhhook ( 995275 )
    Finally someone else thinks that life needs a "Ctrl+f" function.
  • I've been toying with the RFID idea also. So a mysql database of all the tags and the items. Put items in a Contico with a tag, and hierarchically log whats in the box. The database is keyed on items, add a digial picture + description/audio clip. When you are about to search for that item that you know will be in the last spot, consult the database, find the Contico take the item out. Later, a quick scan of the item will reveal what box it needs to go back into. Something like that.


What this country needs is a good five cent ANYTHING!