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Displays Power Hardware

Sonar Software Detects Laptop User Presence 167

Posted by timothy
from the what-are-you-doing-dave dept.
Steve Tarzia writes "A research group at Northwestern University and University of Michigan has released open-source display power-management software that uses a new user presence detection technique. The goal is to shut off the display immediately when the user leaves the computer rather than using slow and error-prone mouse/keyboard activity timeouts. Surprisingly, the mic and speakers of many laptop computers are sensitive to ultrasonic frequencies. Those frequencies can be used to silently probe the laptop's physical environment. This software is based on research published at the UbiComp2009 conference. A Windows binary and source code for Windows and Linux are available for download."
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Sonar Software Detects Laptop User Presence

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  • Mouse/keyboard activity timeout works nicely for that. I rather don't have the computer know if I'm walking near it or not. But it seems we're heading in to this "everyone, and every machine, knows where you are" every day. Thank god I'm already old and not born in to this shit.

    • Re:Activity (Score:5, Insightful)

      by lordandmaker (960504) on Thursday October 15, 2009 @05:34PM (#29762911) Homepage

      Mouse/keyboard activity timeout works nicely for that.

      I find it doesn't. My PC at work has to be configured to require a password be entered on exiting the screensaver, and my password has to be quite complex. If I'm working on something that's not the PC (yeah, we still use paper for things) for longer than the minute, I've got to enter my password to carry on, which is irritating.
      It's less irritating when it kicks in when I'm reading or watching a video or something, but I'd still prefer it not to, and I really don't see the privacy angle on this. It's no idea where I am, just that there's something in front of it.

      But, generally, I don't have much of a problem with my computer knowing all sorts of stuff about me, it's what it tells to who that I concern myself with.

      • Re: (Score:2, Informative)

        by jijacob (943393)
        I use blueproximity on ubuntu. Set the distance and it works pretty well to lock (and unlock) my computer when I am away. The unlock could, I'm sure, be easily spoofed, so if you were in a high-sensitivity location you might want to disable the second half of this software.
        • Re: (Score:3, Insightful)

          by socceroos (1374367)
          I would suggest that if you were in a high-sensitivity location you shouldn't have this software at all. Because, all it would take is for someone to keep your desktop from locking when you walk away by spoofing your bluetooth connection.
      • Re: (Score:3, Funny)

        by geekoid (135745)

        Write a script to move the mouse for you. just a few pixels will do.

      • > Mouse/keyboard activity timeout works nicely for that.

        You know, I'm sure it's just my imagination or a coincidence, but it really DOES seem like Vista on my desktop PC doesn't go into power-saving mode UNTIL it perceives a tiny, tiny mouse wiggle after a long period of inactivity. It seems like I can leave my computer on, walk away, and see it running in full-power mode for hours... then the nanosecond I sit down and bump the desk, it decides to power down the panel. I'm halfway tempted to put a camcor

        • by Sparr0 (451780)

          I have recently noticed that on Vista Home Premium on my laptop, the screen blanks when I am away. When I come back and wiggle the mouse, the first thing I see when the screen wakes up is "Locking your computer" for a fraction of a second, THEN the "Locked, please enter password" screen.

      • by houghi (78078)

        I agree that anybody could be in front of it. A better way might be using just your bluetooth to detect if your phone is at your desk. For me that works as I seldom leave without my phone.

    • Re: (Score:2, Interesting)

      by jhfry (829244)

      Your privacy concerns are valid... however think of the applications for this tech.

      Your instant messenger will know when your available or not.
      Your phone system could direct your calls to you mobile if your away from the desk.

      Proximity may also be important break for the future of voice activated computing. If the computer knows your there, it can listen, and when you leave it ignores any sounds.

      I think there will be applications for this tech far beyond pc's, especially once it becomes common.

      • Re:Activity (Score:5, Interesting)

        by Red Flayer (890720) on Thursday October 15, 2009 @05:47PM (#29763085) Journal

        Your privacy concerns are valid... however think of the applications for this tech.

        /+5 Hat of Greed equipped.

        Oooh, I'm drooling! Let's see:

        $APP detects two people within viewing distance of your monitor. [click here] to upgrade to the appropriate license.

        /+5 Hat of Greed unequipped.
        /+5 Hat of Stealth equipped.

        Oooh, I'm drooling for different reasons. Let's see:

        $APP detects additional person approaching monitor. Autominimize firefox://ridiculous.pornsite.com; automaximize firefox://romanticweekendgetawayswiththewife.toshowherhowmuchyouloveher.com.

        Whew, that was a close one.

        • I'm thinking of a sentient computer system in the basement watching humans move around on a huge floor plan that it has of the building, with sonar coverage shaded.. every computer in the building acting as an active sonar sensor.. every movement into and out of thru hallways counted to track how many people are in each area..

        • Close, but I was thinking $APP detects additional person, yadda, yadda. Autominimize /. ; automaximize corporate intranet.
        • $APP detects additional person approaching monitor. Autominimize firefox://ridiculous.pornsite.com; automaximize firefox://romanticweekendgetawayswiththewife.toshowherhowmuchyouloveher.com.

          Whew, that was a close one.

          That's a very bad idea. The proximity detector will not be able to distinguish between your girlfriend and your wife.

      • Re: (Score:3, Insightful)

        by BitZtream (692029)

        Your instant messenger will know when your available or not.
        Your phone system could direct your calls to you mobile if your away from the desk.

        I think this is EXACTLY what he is concerned with. Do you realize how much information you tell others in the world about you with JUST your IM status? Do you realize how easy it is to use this simple bit of information already to plot crimes? Give me a week of watching little more than the IM status of active IMs and twitterers and I can pretty much tell you wher

        • Re:Activity (Score:4, Insightful)

          by maharb (1534501) on Thursday October 15, 2009 @06:22PM (#29763461)

          IM status can be set manually so if you are concerned about privacy... set it manually. Not to mention just because your SYSTEM knows things about you doesn't mean you must pass it on to any app, especially networked ones. Your system knows all sorts of things that it doesn't readily share.

          Believe it or not people can determine all sorts of things about you IRL just by watching too. In fact, IRL, you are way more prone to being tracked and monitored than online. Imagine, someone can see you leave your house, go in, steal shit, and leave all by watching you. We need to fix that bug IRL asap.

          I can't believe the level of unjust paranoia you are experiencing. The fact is if people care enough to track you, they will be able to. It doesn't matter if you have a laptop that turns off when you leave it or not. Also, how does a 5 minute delay from a regular inactivity time out differ from this so much that this tech is all of the sudden dangerous. It seems to me like people can be monitored via IM just as easy right now as if this was being widely used, just with a tad bit more 'false present' status existing.

          • Re:Activity (Score:4, Funny)

            by Chris Burke (6130) on Thursday October 15, 2009 @07:56PM (#29764375) Homepage

            Also, how does a 5 minute delay from a regular inactivity time out differ from this so much that this tech is all of the sudden dangerous. It seems to me like people can be monitored via IM just as easy right now as if this was being widely used, just with a tad bit more 'false present' status existing.

            Because 5 minutes is the maximum amount of time I can be outside before I get scared of the big ball of fire in the sky and have to run back in. If the crooks think I'm home that whole time, I'll always be safe.

        • by sqrt(2) (786011)

          You can set your client to block anyone you don't have on your list from contacting you or seeing your status. The only people on my IM list are people I know and trust not to rob me...well some of them do like to come over and mooch off my food and beer, but that's a different matter.

        • by ceoyoyo (59147)

          Can you? My IM runs on my phone. So it basically just says I'm always available.

    • Re: (Score:3, Informative)

      by Chris Burke (6130)

      Mouse/keyboard activity timeout works nicely for that.

      Er not really. You need to set it to long enough that it doesn't time out every time you read a page of text (unless you just like idly dragging the mouse around while reading... i don't). Yet you want it short enough that it provides power savings. The LCD screen is a big power hog in a laptop. Being able to turn it off instantly as soon as you walk away, and turn back on when you sit back down, would be the best of both worlds of power savings and

      • Yeah I'd be more worried about the fact that your computer knows every single thing you type, and every single thing you read. ZOMG!

        Read and type into your computer. The computer exploring its environment is new.

        Besides, it's open source. If you're that worried that it's going to report your location to The Man, check the source code.

        It's a technology that can just as easily be implemented in closed source..

        • by Chris Burke (6130)

          Read and type into your computer. The computer exploring its environment is new.

          Webcams.

          It's a technology that can just as easily be implemented in closed source..

          Then don't use a closed source system if you're worried about The Man putting this technology onto your computer and monitoring the output without your knowledge. And if you are using such a system, how in fact do you know it isn't already there?

          Complaining about this in the context of the application stated is kinda silly.

    • by Jurily (900488)

      Mouse/keyboard activity timeout works nicely for that.

      Actually, it doesn't. What if I'm watching a movie with mplayer from the bed? (Yes, Vista starts up indexing and screen savers based on keyboard and mouse input. It sucks.)

      Of course, ultrasonic won't solve this. Who the fuck said I can only use my computer if I'm sitting in front of it? So now if I'm running an overnight batch job, the CPU and I/O are up for grabs?

      Thank god I'm already old and not born in to this shit.

      Me too. I'm 23.

    • by BitZtream (692029)

      So what do you do about the period of time between when you stop typing and walk away, and when the computer times out and locks the system down.

      Too short of a time out and it annoys the piss out of you everytime it locks the machine while you compose a thought in your head, which means you get distracted, lose the thought and have to start over.

      Too long of a time out and when you walk away, I walk up and own you.

      For most people, the longer timeout isn't a big concern, they aren't really doing anything THAT

    • by Fluffeh (1273756)

      But it seems we're heading in to this "everyone, and every machine, knows where you are" every day. Thank god I'm already old and not born in to this shit.

      It's okay, just make friends with your new laptopian overlord and you two should get on just fine.

    • Thank god I'm already old and not born in to this shit.

      Spoken like a truly old person.

    • by couchslug (175151)

      "Thank god I'm already old and not born in to this shit."

      I'm old, there is no god, and I would be fine with "being born into this shit" because "shit" now is MUCH more interesting than it was in 1959 when I was born. (Note to self, "avoid lawn")

      Youngsters, don't believe the lies. The only things about the "good old days" that were worth a damn were that good drugs were cheap and HIV hadn't arrived yet.

    • by Sparr0 (451780)

      I know numerous people who have bluetooth phones linked to their macs, and iChat sets their here/away status based on the state of the BT connection. This is particularly annoying when someone walks PAST their desk during the work day.

    • by ceoyoyo (59147)

      Right, because it's much worse for the computer to know there's something in front of it as opposed to just knowing there's someone typing or moving the mouse.

    • Thank god I'm already old and not born in to this shit.

      Another benefit of being old is that you won't hear the annoying ultrasonic chirps like us young people do :)

  • Safe? (Score:3, Funny)

    by DoofusOfDeath (636671) on Thursday October 15, 2009 @05:25PM (#29762787)

    Damn, now PETA is going to bitch about what happens when dolphins use these laptops.

  • by gpronger (1142181) on Thursday October 15, 2009 @05:25PM (#29762793) Journal
    Don't know if I type slow, think slow, or both, but one of my pet annoyances is when the screen saver kicks-in as I'm staring at the screen in thought (sure I know how to set it, but I am not always in front of my own PC, and oft away and then back a lot through the day).

    If this will simply tell the OS, hold on, he's sitting there doing something, I'd find it a pretty neat idea.

    Greg
    • I, too, often find myself looking at a screen for extended periods of time without touching the mouse or keyboard, while I, ah... read the articles. Nothing ruins a good article more than having the screen saver start up right as you are about to finish.

    • by schon (31600) on Thursday October 15, 2009 @05:39PM (#29762983)

      Something like this has been available for KDE for ages, only it uses Bluetooth.

      You tell it to listen for your phone - when you leave your desk (presumably with the phone in your pocket/holster/etc.) the screen lock kicks in.

      • Of course if you happen to charge your phone near your computer, you're screwed.

      • Yes, and I had it running on OSX about 5 years ago too as part of Salling Clicker.

        It's just remote control software, but one of the functions was to detect the presence of the phone.

        Alernatively you can turn up the volume as you walk away too, or pause music, video, etc.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      Don't time your screensaver so aggressively. Turning the screen off after just a few minutes is useless and just puts unnecessary strain on the backlight (which takes only a limited number of power cycles, unless it is LED).

      I use Ampsoft's Screen Saver Control [ampsoft.net] to manually put the screen into power saving mode with Win+P (and the standard Win+L to lock the screen, if I think that's necessary). I have set the power saving mode to kick in after 2 hours of inactivity otherwise.

    • Hi! I'm Clippy. I see you're trying to think, but nothing is happening!

      credit to one of the three stooges who had that line; "I keep trying to think, but nothing happens."
  • by John Hasler (414242) on Thursday October 15, 2009 @05:30PM (#29762865) Homepage

    I'm just asleep, you insensitive clod! (or does it detect snoring?)

  • I wonder how... (Score:4, Interesting)

    by Whorhay (1319089) on Thursday October 15, 2009 @05:34PM (#29762907)
    I wonder how fine of a resolution is possible with a setup like this with generic microphones and speakers. Maybe it would be possible to use this as a biometric lock on a computer system. It could function as a facial recognition check using the ultrasound picture or series of pictures of your face. Lighting wouldn't affect it and someone couldn't simply use a picture of you to try and fool the camera. Even a bust of your face wouldn't work the same unless it accurately simulated your bone structure and flesh.
    • by BitZtream (692029)

      Yes, because your generic PC speakers and mics which are in different configurations on every model of laptop out there are made to produce images.

      What this will give you is 'there is something large near me, approximately X far away from this computer. Where X is somewhere near about the average distance between the user and the speakers and the user and the mic.

      If someone ACTUALLY wanted to implement this tech, they'd just stop putting the IR unit on laptops in weird places such as the front edge or the

      • Re: (Score:3, Interesting)

        by maxfresh (1435479)
        I agree that a webcam would do a far better job than speakers and mic, but they couldn't use body heat to do it.

        Although a ccd or cmos sensor in a webcam, or most any other digicam, is sensitive to IR as you mention, it is not sensitive to the thermal IR of body heat. Most digital cams are capable of IR sensitivity out to about 1um, if you remove their IR-cut filter. The human body with a skin surface temp of about 305 Kelvin emits most of its IR energy at a wavelength about 10x longer than this, or 9.5um
        • Re: (Score:3, Interesting)

          by Z34107 (925136)

          Asus ships the software you're describing with laptops they sell; it came on mine. It takes a bunch of snapshots of your face through the webcam (you're supposed to rotate your head) and then if it sees your face at the login screen, it logs you in.

          They call it "SmartLogon."

          • Re:I wonder how... (Score:5, Insightful)

            by tkw954 (709413) on Thursday October 15, 2009 @07:38PM (#29764215)

            Asus ships the software you're describing with laptops they sell; it came on mine. It takes a bunch of snapshots of your face through the webcam (you're supposed to rotate your head) and then if it sees your face at the login screen, it logs you in.

            So all I need to log on to your computer is a lifesize photo of you, or alternately, your severed head?

            • by Z34107 (925136)

              Potentially! You also need to be in the same room, facing the same wall, so something silly like a different background doesn't prevent you from logging in.

              After formatting the laptop, I did not reinstall that software.

    • by CAIMLAS (41445)

      I don't think the 'generic' functionality of the speakers or microphone would make much difference. They are all of at least acceptable quality these days, even on laptops (albeit, usually very small).

      I'd think this technology would be quite limited in a desktop, actually - unless the speakers and microphone are built into the LCD, at least. There'd be a great deal of sensitivity to ambient noise, machine noise, and the positioning of the speakers/microphone to each other; if they're not able to effectively

  • Headphones (Score:4, Insightful)

    by quantumphaze (1245466) on Thursday October 15, 2009 @05:36PM (#29762939)

    This wouldn't work with headphones plugged into the computer unless you can get the laptop's built in speakers working independantly (it can do it, old Ubuntu 7.10 had them on separate mixer controls on my laptop). But desktop users usually have their powered speakers off when using headphones.

    Does anyone have an idea on how to solve that? You could put out ultrasonic sound through the headphones that get blocked when used, but it could damage your hearing depending on how loud it needs to be to get picked up by the microphone.

    • by sakdoctor (1087155) on Thursday October 15, 2009 @05:43PM (#29763025) Homepage

      The solution to this, and ALL life's problems is to uninstall pulse audio.

      • by gehrehmee (16338)

        Not at all. Pulseaudio would actually make it much easier to select a second, cheap usb microphone/speaker set while your normal audio happens on your good speakers/headphone/mic.

      • The solution to this, and ALL life's problems is to uninstall pulse audio.

        I keep hearing that. Am I the only person who had consistent problems with sound in linux which all went away the very moment ubuntu adopted pulse audio, when suddenly everything just worked perfectly?

        I mean, it's not that I don't believe you guys, but based on my experience, fixing the pulseaudio bugs that are currently giving you guys problems is probably a better option for distros than dropping pulseaudio.

      • by ksheff (2406)
        Why do most of the linux distros install pulse audio if most of the users hate it? I haven't had a problem with linux sound from before the RH6.x days until I installed a version of Fedora with pulse audio. After tweaking the parameters so it doesn't freeze up or skip, now the audio is a slightly higher pitch (not quite as bad as an "Alvin and the Chipmunks" recording, but noticeable). There has got to be a redeeming feature to it, but I'll be damned if I know what it is.
      • Re: (Score:3, Interesting)

        by CAIMLAS (41445)

        That.

        Personally, I went back to just using ALSA + internal alsa mixer. That kinda sucked (couldn't get it to consistently mix, particularly with Flash, and it would frequently result in poor quality crap while doing so), so...

        I went back to what I was doing a decade ago: use ESD (wherever possible). I suppose I could use JACK or something else, but it does a good enough job and I'm not continually irritated with alsa dying outright due to different things vying for -whatever-.

  • by ArbitraryDescriptor (1257752) on Thursday October 15, 2009 @05:45PM (#29763051)
    And dimmer switches, cordless drill battery charges, and even a really annoying slice of whatever frequency god damn bats chatter at. In short, my super power is above average HF hearing. Hooray for me...

    Now, I like this idea, it's neat, I just really hope it operates well over 18khz so my head does not explode all Scanners style when I walk into a room full of laptops.
    • by Verdatum (1257828)
      Damnit, good point. At my last hearing test, I maxed out the tone generator. It's got me curious enough to try it out to see how irratating the tone is. One could do plenty of fun hacks with this if it actually works as well as one would like.
    • by Jay L (74152) *

      Likewise. I'm 38, and I think my upper limit's dropped to below 17KHz, but still above the CRT flyback frequency (15.6?). Worse.. I seem to recall that exposure to high-frequency noise is what -causes- the loss of high-frequency hearing as we age (the hair cells become brittle and eventually snap, or something like that).

      If I'm right, this "high-frequency" sonar could actually cause hearing problems. Bad. The white paper says they're using 20KHz tones. I wonder if the average laptop speaker/mic/OS can

      • by adolf (21054)

        The speakers and mic will deal with higher frequencies (30-40KHz) just fine, it'll just be attenuated more both going out and coming back in (which can be resolved by just turning things up a bit more, and killing the battery a little quicker).

        A better question is: How will the electronics handle it? Even if the laptop has a codec capable of, say, 96KHz sampling, that doesn't mean that the rest of the audio path (particularly in a laptop) is in any way capable of passing such frequencies. It's very likel

      • by Fred_A (10934)

        Likewise. I'm 38, and I think my upper limit's dropped to below 17KHz, but still above the CRT flyback frequency (15.6?). Worse.. I seem to recall that exposure to high-frequency noise is what -causes- the loss of high-frequency hearing as we age (the hair cells become brittle and eventually snap, or something like that).

        Here you go then, the problem elegantly solves itself.

    • Re: (Score:3, Informative)

      by marcansoft (727665)

      Dimmer switches buzz at 50/60Hz (with lots of metallic-sounding harmonics). Everyone hears those. Better designed ones make less noise. Battery chargers and power adapters in general (of any kind) either buzz at 50/60Hz (transformer based) or at a higher frequency (switching type). Poorly designed switching converters might operate in the audible range - I have a few that can definitely be heard. Most good ones are well above 20Khz. CRT TVs operate at ~15Khz; I hear those too. CRT monitors operate well abov

    • Re: (Score:2, Interesting)

      by Khith (608295)

      I can hear at least up to 20kHz (as high as my speakers' frequency response goes, so I can't test any higher) and it really IS a pain sometimes. The most useful thing I've been able to do is remind them that they left the TV on in the other room. "But I turned off the power and the screen is black.." No, you turned off the power to the cable box which cut out the image and sound on the TV, but I can still hear the flyback transformer. Of course this doesn't work on LCD TVs, though they sometimes just hum

      • by mcgrew (92797) *

        Kid, 31 is pretty damned young. Most people start losing their hearing later, and it's the result of noisy environments -- working in a factory, construction, etc. If you're an office drone your hearing is going to last a whole lot longer, unless you're a hunter (guns are LOUD) or play in a rock band or something.

    • I have a simple solution to that problem. I used to have similar problems (though not as bad) - the 15KHz whistle of the old color TVs used to bug me. But during my misspent youth I spent several years listening to lots of loud music - 10 feet from the speakers at rock concerts, etc. Now, other than a constant ringing in my ears, I'm fine! And I no longer hear HF audio, so no more annoying whistles for me :D Try it, soon you'll be as deaf as Pete Townsend!

      (FYI, the last band I was in used in-ear monito

    • by CAIMLAS (41445)

      Huh. You mean that isn't normal? I can hear all of those things, and I've always been highly agitated by high-pitched sounds as well. The bats drive me crazy during summer nights, and I've been tickled pink since LCDs have replaced CRTs wholesale. The one that irritates me the most, though, are power supplies on brown power, or just poor quality power supplies, and anything that's performing PWM with a high wattage. I HATE cooking on an electric stove and using the microwave.

      I haven't had my hearing tested

  • How will this benefit the general user though? There are many times that I get up but still want my laptop to be running for example, I can leave a music player on, hook up my laptop to a projector to play a movie, or a load of other things that this would prevent from happening.
  • by rtfa-troll (1340807) on Thursday October 15, 2009 @05:59PM (#29763231)
    It would be nice if they would make the software license clear. Even if just to say that "this is government sponsored and so available for copying with no restrictions". Also at the bottom of the page they say '"Windows" is a registered trademark of the Microsoft Corporation.' but forget to mention that Linux is a registered trademark of Linus Torvalds.
    • Re: (Score:3, Interesting)

      by olau (314197)

      You got that backwards. What they should do is deleting the remark about Windows. Anyone succumbing to the (tm) crap should have their head examined. Every time somebody writes "registered trademark", god kills a kitten. It's true. Between us, we just killed two. No, I'm not going to write it again.

      Now someone is going to say legal blahblah necessary blahblah. But there is something wrong if fear of a big corporation is making you write that kind of kitten-lethal nonsense every time you mention a product ma

      • someone is going to say legal blahblah necessary blahblah.

        No; I'm going to say that some / most trademarks are useful (like Linux(R)). If the Linux(R) trademark gets diluted and became a common term for operating system that would make me sad (on the other hand I don't see that Windows has the right to exist - it's pretty clear they only escaped from the Lindows case by paying their way out). In the case of Linux(R) I don't see that it causes any problems to anyone. IF, by reminding people that Linux(R) is a registered trademark of Linus Torvalds God kills a ki

    • "so available for copying with no restrictions". Why does everything need a license? If that's all they say then there is no license. It's public domain. Do what you want.

      Licenses exist for one reason only - to restrict what you can do with something. If there is no license, you can do whatever you want.

  • ...tie power savings to the manual screen lock feature. In Windows, the WindowsKey+L locks the workstation. It would be great if a second or two after the workstation is locked, the monitor turns off and the drives spin down. That would provide good power savings and avoid the problem of having to determine whether or not the user really wants their workstation to conserve energy.

  • Why ? (Score:3, Interesting)

    by smoker2 (750216) on Thursday October 15, 2009 @06:25PM (#29763489) Homepage Journal
    What's wrong with a keyboard shortcut key or assigning a function key ? It's a laptop, you probably don't just walk away frequently and leave it unattended. Not anywhere I know anyway.
  • by Kazoo the Clown (644526) on Thursday October 15, 2009 @06:33PM (#29763565)
    Just tell me where I put the postit note or soda bottle to fake it out so it thinks I'm there all the time...
  • I wonder if this will be like a dog whistle, and end up being something that will drive Fido crazy?
  • by geekoid (135745) <dadinportland.yahoo@com> on Thursday October 15, 2009 @07:08PM (#29763925) Homepage Journal

    Could be built. Interesting.

  • If the mechanism could be tweaked properly such that it can hear the difference between soft breathing and fan harmonics, this would be a great module for an alarm clock. It wouldn't bother sounding off when you're out of town, and it would automatically turn back on if you were there originally but haven't left for work yet. (too lazy to find the link to the guy who did the same general thing, instead by detecting his body weight added to the bed.)
  • I thought for sure I'd have seen a remark by now that said something to the effect of computer pings YOU!
  • Surprisingly, the mic and speakers of many laptop computers are sensitive to ultrasonic frequencies.

    For anyone who actually knows about how microphones and speakers work, it's not particularly surprising at all. Timothy needs to go to school, and learn a little bit of physics.

  • I can see so many of them freaking out cause of this.

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