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Any way to find a lost Kindle inside a house?
- ctdonath 7y agoTL;DR - he found it, by sending a giant PDF thereto and recording network traffic info via 3 computers, extracted the signal strength of the desired device (Kindle), and mapped the convergence of 3 spheres of that signal strength, locating it within a couple feet.
- thiagomgd 7y agoCleaning/organizing the house would be much simpler and useful I guess...
- toomuchtodo 7y agoThis you must repeat. Next step is to automate the manual process. Like Tile, but no extra cost and using existing home network infra. "$Home_Automation_Wake_Up_Command, where did I leave my $device", with $device friendly name associated with hardware address. RF engineering is just so darn awesome, it can appear to be magic.
- sl1ck731 7y agoThe simpler solution is to just remotely set off an alarm. I do this frequently with the "Where is my Android" thing. Internet-enabled devices should include this capability by default, anything more is just over-engineered.
- toomuchtodo 7y agoNot supported by all devices. It's unlikely it's easier to get everyone to agree to support this feature than a firmware update to wireless access points (which might even be open source depending on the hardware specd) to support time of flight ranging. If you can ship it, ship it. Don't wait on someone else.
- sl1ck731 7y agoUnless I'm missing something your assuming multiple (3 minimum access points, having worked on a similar project our accuracy required more to make up for inconsistencies and multi-level facilities) at home (where I get away with just a single one) and that they have been calibrated to know where they are in relation to each other.
- toomuchtodo 7y agoYes, I am assuming that is more likely than convincing manufacturers to support alert functionality natively. Considering the rise of wifi repeaters (Google, Eero, Netgear, ec) and other IoT devices, I don't believe my assumption is far fetched. Consumers have smoke detectors, cameras, garage door controllers, and water sprinklers on their wifi now.
- beatgammit 7y agoYou could make a simple 3-part product that does just that. You place them in various parts of your house, they calibrate together (play an inaudible sound and measure delay), and then have them manufacture traffic to your target device to figure out where it is. I imagine they could be somewhat close together (e.g. same room), which makes setup way easy. I can't imagine it would be very difficult to make, provided small Wi-Fi capable devices are sufficient, it just needs some work on the details.
- yjftsjthsd-h 7y agoAs yak shaving goes, I'm not sure how to compare "clever technical hack" vs "clean the house"...
- JustSomeNobody 7y agoEven easier would be to always return the kindle to a certain spot.
- everdev 7y agoKids and getting older make this a less bulletproof solution.
- JustSomeNobody 7y agoKids can learn not to touch someone else's kindle. And the older I get the more I use habits to help me.
- blazespin 7y agoOr, read paper books - won't have a kindle to lose
- JustSomeNobody 7y agoNope. Now where did I put that paperback I just had???
- Lendal 7y agoMy solution would be to hire an estate sale company, who will bring in a team to inventory every item in the house while selling it off to the general public. Give them instructions to sell off everything except Kindle readers. By the end of the week you will have a clean, empty house except for one pile of Kindle readers. Problem solved!
- SketchySeaBeast 7y agoSave yourself some up front money and just Marie Kondo it. If it is not your kindle, it does not bring you joy.
- lonelappde 7y agoThe estate company will sell my trash for me.
- beatgammit 7y agoI wonder if RFID would be an effective solution here. They're cheap, small, and don't require batteries, so all you'd need to do is make a device that can generate a powerful, directional signal and you could quickly locate whatever you're looking for. I'm not an expert on RFID, but it should be a workable solution, and would work even if the device is off (e.g. ran out of battery).
- arthens 7y agoWho said the house was not organised/clean? I don't think it's a fair assumption at all. Even ignoring the fact that this wasn't his house (so organising it was probably not an option), he found the kindle in a closet... meaning his mom (or someone else living in the same house) cleaned/organised it and then just forgot about it.
- jborichevskiy 7y agoUsually a TLDR of a longer post lets me skip it -- not in this case, I was too intrigued. Kudos to them for pulling that off!
- daemoncoder 7y agoI found the break in a 10m extension cable, by measuring the capacitance at each end and calculating the ratio of the two values. This predicted a break at roughly 1m from one end. Then started probing the cable from 10cm towards the ”short” side, moving towards the long side. Found the break within 15cm, saving roughly 9m of cable.
- emilfihlman 7y agoNow that's pretty sweet!
- robocat 7y agoUnless there was an obvious reason for the break then there could easily be another "nearly broken" fault in the cable e.g. if break was due to stretching. A partial break has the risk of local overheating. So perhaps you should biff the cable anyway if it is likely to be unsafe?
- daemoncoder 7y agoThis is a good point - the cable is probably 20+ years old and has been used for weed eaters and lawn mowers. It's been regularly uncoiled and re-coiled, not always correctly. The correct way is using the over-and-under technique: https://www.popularmechanics.com/home/tools/a15873/over-under-the-foolproof-way-to-coil-extension-cords/ https://www.popularmechanics.com/home/tools/a15873/over-unde...
- dr_orpheus 7y agoThat's pretty clever. Also if you are interested (not 100% applicable because it's not something most people can do at home) there is a practice for finding breaks/partial breaks in cables using time domain reflectometry (TDM) [0]. You send a pulse in to one end of the cable and measure how long it takes for some reflected energy at the break to return. It's pretty cool stuff and you only need access to one side of a cable. I have used this in my job for finding discontinuities in large RF cables. If you do have some electrics equipment at home (o-scope, sig-gen) you can make do it yourself [1] [0] https://en.wikipedia.org/wiki/Time-domain_reflectometer https://en.wikipedia.org/wiki/Time-domain_reflectometer [1] https://www.allaboutcircuits.com/projects/build-your-own-time-domain-reflectometer/ https://www.allaboutcircuits.com/projects/build-your-own-tim...
- jrootabega 7y agoSounds like he would enjoy playing EVE
- metalliqaz 7y agohe has to stop lending his mom stuff
- Rerarom 7y agoI keep my Kindle on airplane mode all the time so this wouldn't work.
- bigbaguette 7y agoA lot of people do that to make sure it doesn't update itself without a warning and loose their jailbreak
- close04 7y agoExtending battery life is also a good side (main?) benefit.
- giancarlostoro 7y agoThis is why I do it.
- tudorw 7y agoor wipe your cherished copy of 1984 ;)
- mannykannot 7y agoHa! though 'Farenheit 451' would have made for an even more perfectly ironic incident, had Amazon erased it instead (that book was the first thing I thought of when I heard that Amazon was making a reader called Kindle.)
- chrisweekly 7y agoparent may have been referring to actual incident (sorry no citation handy) in the early days of kindle devices, in which 1984 had its contents remotely altered (ie, subtly changed, not deleted). to me that's the most apt conceivable book title to make a pretty chilling point about trustworthy media.
- deleted 7y ago[deleted]
- russfink 7y agoRaspPi project, anyone?
- deleted 7y ago[deleted]
- umvi 7y agoHe should just attach a Tile to it for next time
- beatgammit 7y agoI don't really understand these things. Wouldn't an RFID sticker work better since it doesn't need a battery? The next step is to make an RFID sensor that can aim a beam so you know precisely where the device is. Those Tile devices are a little big for my taste and I'd much prefer a sticker I could hide somewhere.
- jfengel 7y agoA Tile has a speaker, so once you're in range, you can hear it. An RFID tag on its own just peeps out its own data, but that doesn't help you locate it without additional equipment. You can use a Tile with just your phone. They do make slightly smaller Tile Stickers, which aren't as loud and don't have replaceable batteries.
- folkhack 7y agoAs a lower-tech method I would try just setting up a super low TX power/RX gain on a spoofed access point (same SSID, credentials, MAC, etc.) on my ALFA USB adapter and wave it around as an RF scanning device watching for connected clients. Not sure if it would work as I'm not sure I could get it to be sensitive enough, but I bet you could at least get a rough idea of where the device was without too much trouble...
- ceejayoz 7y agoIIRC, Kindles only connect to Wifi intermittently to save battery.
- girzel 7y agoIn my experience, a Kindle connected to wifi burns through battery like there's no tomorrow. Like a percentage point every half hour. I absolutely keep it on airplane mode to preserve charge.
- Wowfunhappy 7y ago> In my experience, a Kindle connected to wifi burns through battery like there's no tomorrow. Like a percentage point every half hour. It really speaks to the longevity of the Kindle that 50 hours of battery life ("a percentage point per half hour") counts as "[burning] through the battery like there's no tomorrow." Or maybe it speaks to how little time most devices last, I can't tell. (To be clear, your expectations are reasonable, as battery is a key selling point of e-ink Kindles.)
- greggyb 7y agoIt speaks to the other devices. I remember when I migrated from a flip phone to a smartphone a few years ago. I have been frustrated for as many years. One day I realized I could just buy a charger for every location I might stop for a while. Now I am not frustrated at battery life. I am frustrated with the solution. It is not unlikely that this will be my next phone: https://www.thelightphone.com/ https://www.thelightphone.com/ I love the idea of an e-ink phone.
- Henrywallen 7y agoCleaning the house would be much simpler and useful.
- haecceity 7y agoRelevant bash http://bash.org/?5273 http://bash.org/?5273 Couldn't be have just pinged it instead of waiting for update?
- jagraff 7y agoNo, because the Kindle only connects to wifi around 6AM in order to download updates, so it wouldn't be available on the network until then.
- lkbm 7y agoThere was also a famous Register (and apparently Information Week) article about a lost server at UNC: https://skeptics.stackexchange.com/questions/32502/did-a-computer-server-get-accidentally-walled-in https://skeptics.stackexchange.com/questions/32502/did-a-com...
- VectorLock 7y agoDo any of the whole-house Wifi systems have this built in? That would be very cool to have the triangulation be part of the product.
- paxys 7y agoMesh networking is just starting to get mainstream, so I am sure that this will become a standard feature in a few years.
- deleted 7y ago[deleted]
- chipperyman573 7y agoMaybe, but the point of mesh networks is that each AP only has to see one other AP to work, and a device only has to be in the range of one AP. Because mesh APs generally take efforts to not talk over each other, they usually end up less powerful than other routers, leading to mesh setups like this: |--a------| |---------| |--a------| |------j--| |--a---i--| where a are the mesh APs and i is the item you're trying to find. If i can only be seen by the third/bottom AP, it wouldn't be any more useful than a traditional router (because from the perspective of i, it is a traditional router). Even if it could be seen by two APs (like j, for example), you generally need three sources to accurately trilaterate things so unless you have a minimum of three APs covering every single point of your entire house (which will lead to slightly worse performance and way higher spending, probably around three times the price), this probably won't work very well. Or you could buy mesh routers that can all be seen from anywhere in your house... which would kill the point of making your network mesh anyway because then you could just use a single AP from that setup to cover your whole house.
- fulafel 7y agoThey use less powerful TX but it doesn't matter if the location tracking is passive, no? For triangulation, 2 measurement points are good enough if you only need the 2D location: https://en.wikipedia.org/wiki/True_range_multilateration#Two_Cartesian_dimensions,_two_measured_slant_ranges_(Trilateration) https://en.wikipedia.org/wiki/True_range_multilateration#Two... - but of course home wifi environment is full of reflections and attenuations caused by the surrounding structures so straight triangulation doesn't work anyway.
- MrFantastic 7y agoEarly spring cleaning.
- dznodes 7y agoThey are so cheap, just buy another. ;)
- F_r_k 7y agoThey are as cheap as you are wasteful
- bonyt 7y agoHere's a little experiment I made with an ESP8266 to passively search for WiFi AP's (not stations, so not helpful here): https://github.com/tonyb486/ESP8266-WiFiHunter https://github.com/tonyb486/ESP8266-WiFiHunter
- lostgame 7y agoDid anyone else find this solution to be hilariously technical, whereas a simple cleanup might’ve done the trick? Very cool, but struck me as very funny.
- tjoff 7y agoTypical procrastination :) I could totally see myself do the same thing just for the fun of it and to see if it works. Wasting a ton of time when cleaning would be quicker and something that needed to be done regardless. But on the other hand, one probably wouldn't find the time to try out wifi triangulation if there wasn't some need for it. So that is something!
- asdfman123 7y agoYeah, I've thought of very elaborate technical ways to keep track of my keys, phone and wallet. But the best solution is to have just like 1-3 places in your house you're only allowed to put them. It takes a few weeks to get into the habit, but once you do it's incredibly easy to find them again.
- cesarb 7y agoDepending on how big the house is and how much stuff it has (being a parent's house increases the chance that they lived there for long enough to accumulate a lot of stuff), this hilariously technical solution might actually have taken less time than a "simple cleanup". A single cabinet full of stuff can take several hours to properly organize, and a house can have dozens of them. On the other hand, https://xkcd.com/530/ https://xkcd.com/530/
- StavrosK 7y agoWhy not-solve a riddle when you can solve a riddle?
- lkbm 7y agoMy parents have more books than a lot of bookstores I've been to. If a Kindle somehow got shelved or put into one of the boxes of books, it could be a lot of cleanup to find it.
- askvictor 7y agoThe solution presumably requires you to move the receivers around while measuring the signal strength, or am I missing something? Could measuring Round Trip Time for packets be used for easier calculation, or would they be too small to be useful?
- somehnguy 7y agoDid you the read the whole answer? He used triangulation from non moving receivers.
- askvictor 7y agoTrue, I had originally skimmed the answer; now fully reading it it makes some sense, though I still would have thought that obstructions or reflections would make signal strength quite unreliable for this use case. Maybe he got lucky, maybe I'm not a radio engineer.
- catalogia 7y agoAn effective generic strategy to locating missing objects is the Bayesian search theory: https://en.wikipedia.org/wiki/Bayesian_search_theory https://en.wikipedia.org/wiki/Bayesian_search_theory It's been used to find several lost ships, planes, and things of that nature. Of course, a casual application of this approach essentially boils down to "look first in the places you think it's most likely to be."
- alfalfasprout 7y agoThere are so many assumptions baked into a bayesian search inside your own home that it's unlikely to help though. Plus it relies on at least one hypothesis containing the correct search space (i.e the object lies within the search space).
- catalogia 7y agoI agree it's probably not very helpful in this case, though there are some general lessons you could take from it that would be helpful. Considering the likelihood that it would have already been found or could never be found if it were in a particular location can help you prune your search. e.g. > "It's likely it may have ended up on my kitchen counter, but if that were the case I probably wouldn't think it lost. So I should deprioritize looking on counters." or > "There's a good chance it's in my attic, but my attic is cluttered and I'd probably fail to find it even if I looked there, so I should deprioritize searching the attic until other possibilities have been exhausted."
- scotty79 7y agoWait. So I can put few simple wifi-enabled microcontrollers in corners of my apartment and be able to always check where I tossed my phone just by looking at the tv or computer screen? How's that not a product? I could even name few usual zones and have the name of the zone that contains the phone displayed on any screen in the house and on smartwatch. Also I could do the same for smartwatch. Can it be done for bluetooth?
- manojlds 7y agoSmartwatch <-> Phone finding via bluetooth is builtin mostly.
- zamadatix 7y agoBecause most people aren't interested in buying a bunch of devices to plug in at the edges of their house on the off chance it'll catch a lost charged device reaching out via wireless instead of just cleaning ;).
- lonelappde 7y agoI don't think this claim is true. And "Most" is not enough. "Nearly all" is required to eliminate a market for alternative.
- scotty79 7y agoI guess I'm not most people because I'm definitely doing it. Most frantinc searches of my phone happen as I'm about to leave the house in hurry. Cleaning is not an option then. I would have to be 'organised' which I absolutely abhore and want to avoid at all cost. So far my solution was to just have a second phone in a fixed place so I can call my main phone and locate it by sound. But the wifi triangulation thing sounds like way more fun.
- pubutil 7y agoYou might benefit from a Tile. Put one on your keys and/or wallet, they locate bidirectionally via sound blasting (e.g. keys > phone, phone > keys). Or maybe Bluetooth beacons would work just as well? Though if you’re in it for the fun factor then go for the wifi option!
- herpderperator 7y ago> To triangulate the signal (for a 2D location), draw a chart with the position of the laptop wifi receivers and for every pair of receivers, draw a line perpendicular to the line going through the points in a point inversely proportional to the square root of the mW power values, as the signal drops of proportionally to the square of the distance (for 3D use at least 4 receivers and a surface between the points). It's worth noting that this isn't triangulation, it's trilateration. Triangulation involves angles. GPS does not do triangulation, it does trilateration. Similarly, here we are doing trilateration.
- rahimiali 7y agoI can't imagine that this could have "just" worked (simply trilaterating using signal strength). If the laptops & kindle were in outer space, I'd believe it, but wifi signals indoor get attenuated by obstructions, curve around things, and bounce off of things. This is one reason wifi localization uses fingerprinting instead of trilateration. I'm guessing OP primarily ended up using the signal strength from one of the laptops, and just did a hot/cold chase through the house.
- sundarurfriend 7y ago> Found the Kindle using the sniffing technique described below. I read this and, having a puppy at home, I interpreted it as actual sniffing i.e. scent detection (since I've been thinking about training her in that). The only question in my mind was whether he had trained a dog to do it or did it himself Feynman-style.
- fulafel 7y agoThere's an entire existing engineering field about this: https://en.wikipedia.org/wiki/Wi-Fi_positioning_system https://en.wikipedia.org/wiki/Wi-Fi_positioning_system Here's a paper from 2015 that is vocers exploiting the multiple antennas in recent access points, and other techniques: http://conferences.sigcomm.org/sigcomm/2015/pdf/papers/p269.pdf http://conferences.sigcomm.org/sigcomm/2015/pdf/papers/p269....
- christefano 7y agoWunderfind might help. It just hit the App Store this week, and the Pro version is free for a limited time. (No connection to the developer.) https://apps.apple.com/us/app/wunderfind-find-lost-device/id1458601441 https://apps.apple.com/us/app/wunderfind-find-lost-device/id... Discussion at https://reddit.com/r/Wunderfind https://reddit.com/r/Wunderfind
- hkai 7y agoWow, first world problems I never had trouble finding my phone in my 150 sq ft apartment TC 65000