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Boston University Working On LED Wireless Networks 179

Madas writes "This article on Absolute Gadget details how researchers at Boston University's College of Engineering are working on devloping wireless networks that use LED lights instead of normal radio waves. This research apparently has other uses in the automobile industry. Apparently the LEDs could warn you if the driver in front has put the brakes on so could avoid hitting the car in front. Personally, I'd use the vision balls that are in my thought box."
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Boston University Working On LED Wireless Networks

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  • by arizwebfoot ( 1228544 ) on Thursday October 09, 2008 @02:46PM (#25318129)

    Apparently the LEDs could warn you if the driver in front has put the brakes on so could avoid hitting the car in front

    Dude aren't those called brake lights?

    Oh Well, Bad Karma and all . . .

    • Re:Brake Lights (Score:4, Insightful)

      by hey ( 83763 ) on Thursday October 09, 2008 @03:04PM (#25318441) Journal

      Could be used to communicate the rate at which the brake pedal is pressed.

      • Re: (Score:2, Interesting)

        by T3hD0gg ( 908064 )
        Why don't they do that with regular brake lights?

        You could have it so the brightness of the brake lights describes how far down the pedal is. You could even have it so if there's a sudden, heavy push to the pedal, they could blink rapidly.

        Also, the people who ride their brake pedal won't be an annoyance to other drivers because their little pedal tap won't create a huge change in the brightness of their brake lights.
        • Re: (Score:3, Insightful)

          by MightyYar ( 622222 )

          I can think of two reasons:
          1. A pressure sensor like that would be more complex and prone to error - probably require some kind of calibration.
          2. Psychologically, you probably don't want people ignoring faint brake lights. I can already hear people complaining about how, say, Toyota uses brighter brake lights than Chevy and so so-and-so got confused about how hard the person was pressing the brake. It would also be hard to interpret the lights in varying light levels.

          • Re: (Score:2, Interesting)

            by cyclomedia ( 882859 )

            Just replace the top/middle/third brake light with a large-ish display that shows the speed of the vehicle, if it starts dropping rapidly you know you need to brake.

            Also handy when you're in fast moving traffic and round a bend to catch up to a vehicle, for several seconds you have no idea if it's stopped, going very slow or just slowish. if there's a fat "32" on it and your dash reads "64" you know to get over into the next lane.

            If your dash display was also digital then when you crossed a border into a me

        • I have a friend that owns a (new) Mini Cooper and having been on a run with the local Mini group one of the leaders had his central brake light replaced with a slick LED unit that blinked a couple of times every time he hit the brakes. Under the physical and mental strain of doing 30 MPH around multiple hairpin turns down hill this can help quite a bit in knowing he's braking while still using your peripheral vision as you follow the outside or inside curve of the road.

          And believe me, these guys *stand* on

      • by ozphx ( 1061292 )

        A whole bunch of modern cars switch on the brake lights when you take your foot off the accelerator quickly (presumably in order to brake).

    • Re: (Score:3, Funny)

      by Anonymous Coward

      Vision balls?

      Single point of failure if you ask me. What type of nerd are you?

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      Not to mention that such a feature (automatic braking based on the car in front of you) already exists. It uses radar, it just has to bounce a signal off the car in front of it. As it turns out, when a car starts braking, it starts to slow down, and that can be easily detected!

      In fact, networking using LEDs also already exists: it's that IR port that no one uses any more because it sucks.

      So congrats, Boston, you finally discovered LEDs and technology that has existed for what, two decades now?!

      It does expla

      • by kesuki ( 321456 )

        yeah it already exists and already can got to 100 mbit, but it's also short range as well. []

        perhaps they are working on longer range communication, perhaps they are using frequencies other than infrared. it is true that bluetooth has basically killed IrDa. really, the only thing infrared data does better than radio wireless is be 'snoop' proof*. since it is directional, it can only be received by the intended recipient. this makes it ideal for certain

        • Re:Brake Lights (Score:4, Insightful)

          by kesuki ( 321456 ) on Thursday October 09, 2008 @06:55PM (#25321841) Journal

          should have RTFA, this is about using LEDS over ambient lighting, to broadcast data via power lines, to every light in the room, which is then received by every data device.

          weird, but a quite a bit different from IrDa for one, it's using visible light. i can't think of any real reason to be broadcasting large amounts of data to multiple devices in a single room for consumer markets, but for instance a usb dongle on a laptop, and everyone in a lecture hall could receive all the notes from the class all at once, while listening to the lecture.

    • Re: (Score:2, Insightful)

      There is so little in TFA that has to do with cars. I don't understand why this was chosen as a focus of the summary.
    • by Lumpy ( 12016 )

      What I get a kick out of is that this "automotive" use will fail miserably. first ignore that the auto makers are hostile and refuse to make things interoperate we'll only have fords responding to fords and so on.

      Plus, every IR/light based communication system I have ever used fails 100% when exposed to direct sunlight. The sun can outpower any led you put in a taillight.

      • Just goes to show what peoples' priorities people are.

        This kind of thing would lead to people driving with their knees on the wheel, cell phone in one hand and a latte in the other, waiting for their cars to tell them to press the brake pedal. Let them do it -- I'll ride the bus while the rest of the nation competes for the coveted Darwin Award.
    • Re: (Score:3, Interesting)

      by jmorris42 ( 1458 ) *

      > Dude aren't those called brake lights?

      The light part would remain, to tell YOU the guy in front is braking. But now imagine that every light on every vehicle were also beaconing a unique identifier along with current speed and acceleration. You car would notice a car in front of you (because it has been seeing it with the front mounted sensor for a bit, thus it has to be in front and it could likely even know it is in the same lane) just started drasticly slowing down and you haven't hit your brakes.

      • by blair1q ( 305137 )

        So the guy in front of me can send me spam through my HUD?

        Fuck that.

        • Or far worse, some tool walking along the footpath can press a button on a $10 keychain that he bought off ThinkGeek and make every car within 10 meters lock up its brakes.

          It's like using your garage door opener to scare that guy who just screamed past you by setting off his radar detector (don't think this one works any more though).
  • IRDA Anyone? (Score:3, Insightful)

    by neowolf ( 173735 ) on Thursday October 09, 2008 @02:46PM (#25318137)

    Wasn't there just a story about this on Slashdot two days ago?

    Anyone else remember the exciting world of IRDA? How is this really going to be that much different (or better)?

    • Same as the difference between 10baseT, 100BaseT, 1000BaseT- same shit, different clock speed
    • by argent ( 18001 )

      IRDA worked just fine, there's nothing wrong with IRDA. It got killed by Bluetooth, which requires more power and has less inherent security.

      • Re: (Score:3, Insightful)

        by neowolf ( 173735 )

        No- it got killed because of reliability over any kind of a distance issues. You also had to always make sure the ports were clear of obstacles, which isn't very practical in an office or mobile environment. You could "kill" a network device (like a printer) with a post-it note.

        I still remember (not-so-fondly) printing from my Palm device to an HP printer with IRDA. That was almost as agonizing as waiting for a 2400-baud modem to connect, and about as fast too. I also remember creating "ad-hoc" IRDA network

        • Re:IRDA Anyone? (Score:4, Insightful)

          by argent ( 18001 ) <peter@slashdot.2 ... m ['6.t' in gap]> on Thursday October 09, 2008 @04:19PM (#25319777) Homepage Journal

          There are certainly things you can do with bluetooth that you can't do with IRDA. I wouldn't want an IRDA headset, and I wouldn't use it over a distance, but BT gets used for all kinds of things that USB (yes, real wires) Wifi, and IRDA are better for.

          Printers? Stick them on a network, don't wire them to a computer. If you want wireless access to a printer, use Wifi and Zeroconf/Rendezvous/Bonjour.

          Headsets? Perfect application for Bluetooth.

          Sharing files, PDA to PDA? You *want* short range and directionality. IR is ideal.

          Mice and keyboards? Been there, done that, got the dead batteries and incomplete mess

        • by Kizeh ( 71312 )

          I think I am old enough to recall that. There was talk about IrLAN based on IrDA, with pods in office ceilings that computers, printers etc. would connect to for networking. The bandwidth wouldn't have been sufficient to last us through the Internet explosion, but the idea of free range optics of those days were apparently ahead of their time.

    • by ceoyoyo ( 59147 ) on Thursday October 09, 2008 @03:18PM (#25318657)

      These look pretty. Maybe they'll use blue LEDs. Everything is better with blue LEDs.

    • Anyone else remember the exciting world of IRDA?

      Not only that, I remember Arcnet.

      Very early on in computing there was Datapoint's Arcnet. It was a token ring network that tied their early desktop machines (the SSL IC machines whose instruction set spawned the 8008) and their associated fileservers.

      Options for interconnection included:
      - copper cabling
      - "Arclight" building-to-building infrared links. (They had separate transmitting and receiving lenses maybe a foot across each and were good

    • Anyone else remember the exciting world of IRDA? How is this really going to be that much different (or better)?

      Well, nowadays they have these super bright LEDs that they didn't have last century, so range may not be as much of an issue.
  • by dmomo ( 256005 ) on Thursday October 09, 2008 @02:53PM (#25318243)

    > Personally, I'd use the vision balls that are in my thought box."

    Personally, I think the zipper gets in the way.

  • Light should be less susceptible for jam and interference.

    But on the other hand, it would expose your position. (And they also have night goggle for IR light)

    • Less susceptible to Jam and Interferences ?

      Actually the good thing is that instead of tinfoil hats, we can just use paper hats !

  • Trust issues (Score:5, Insightful)

    by psydeshow ( 154300 ) on Thursday October 09, 2008 @02:57PM (#25318323) Homepage

    But the question is, do you REALLY trust the car in front of you? What if it just randomly transmits a "braking now!" message in order to cause other cars in the vicinity to put on their brakes?

    It would be cool to see what you could do with this to improve traffic flow and autopilot in a controlled environment, but out in the real world the trust issues get pretty dodgy.

    • Re: (Score:3, Insightful)

      by qoncept ( 599709 )
      Something tells me you never pulled any pranks that were funny.
    • The idea of P2P traffic systems is great in theory, but it fails as soon as someone decides to make a greedy or malicious node.

      I've put a lot of thought into it because I like the idea, but I just can't get over the problem of greedy or malicious nodes without a government certificate system, like a digital license plate.

      The problem then becomes there are all sorts of surveillance issues with government knowing which cars came into contact with which other cars and then also what happens when the certificat

    • What if it just randomly transmits a "braking now!" message in order to cause other cars in the vicinity to put on their brakes?

      That's possible now. Its called tapping your brake.

      • That's possible now. Its called tapping your brake.

        Yes, and so many people do it for no reason that a brake light by itself doesn't have much information content.

    • by Jay L ( 74152 ) *

      What if it just randomly transmits a "braking now!" message in order to cause other cars in the vicinity to put on their brakes?

      We already have that in the analog world. My first car, a 1979 Pinto with a big dent on the side, would engage the backup lights if you moved the stick shift toward reverse - even while you were still in neutral. F'rinstance, if you happened to be driving on the highway.

      Combine that false alarm with the Pinto's well-known tendency to blow up - reenforced by my "I XPLODE" vanity p

  • by XxtraLarGe ( 551297 ) on Thursday October 09, 2008 @03:02PM (#25318397) Journal
    They should make the LED's look like characters from Aqua Teen Hunger Force! []
  • Amazing (Score:5, Funny)

    by Dan East ( 318230 ) on Thursday October 09, 2008 @03:03PM (#25318425) Journal

    This is amazing. Maybe they can put this technology in a small box that I can point at my TV so I don't have to get off the couch to change channels. Maybe they can use IR LEDs to reduce interference from ambient light which is mostly in the visible spectrum.

    • Your ideas are crazy and impractical.
      Also, they would cripple the helper monkey industry you heartless bastard.

    • Re: (Score:2, Funny)

      by Wescotte ( 732385 )

      That will never work. What happens when you want to change the channel but can't see the TV? IR only works with line of sight.

  • "Balls" and "box" are terms that get me in trouble. Kind of like the circular queue discussions where the pointers where named "head" and "tail."
  • Stupid summary (Score:4, Insightful)

    by hcdejong ( 561314 ) <hobbes@[ ] ['xms' in gap]> on Thursday October 09, 2008 @03:11PM (#25318541)

    Cars communicating with each other is a good idea, and being worked on. Signalling that a car is braking is one obvious use, despite the stupid comment in TFS. Having the car react automatically to the car in front saves the 1+ second reaction time of the human driver, making you less likely to rearend someone. The only drawback is that you're relying on external inputs. This system won't stop for a pedestrian, or an older car (which doesn't broadcast its intentions in a machine-readable way), for instance. Radar seems a better bet for this particular application.
    But there are more uses for a network between cars. Relaying congestion data is one, you could synchronize cars so they run at the same speed instead of harmonica-ing all the time (prevents traffic jams), etc.

    Using LED signalling instead of radio might be a good way to avoid the problems with RF (interference, limited number of channels available).

    • by zyl0x ( 987342 )
      Obviously not speaking for the majority of horrendous drivers on the roads today, but as an excellent and safe driver, I don't trust anyone or anything other than myself driving my car. No matter how fast a computer works, it has nothing on a human brain in a life-or-death situation. Our brains are much more capable of taking in way more information into consideration than a computer. As a programmer, I just don't trust computers enough to make life-or-death decisions for me. Unintended side-effects, buggy
      • Dude, your brain takes a full second minimum to recognize the problem and start pressing on the brake peddle with any significant force. 1980's calculators could respond to external stimuli several orders of magnitude faster.

        Computers can supplement driving performance no matter how good of a driver you, and everyone else, thinks they are. An existing, yet primitive example of this is ABS.

      • As an excellent and safe driver who has been caught out by the 1-second delay between "oh shit" and physical action taking place on at least one expensive occasion, I'd welcome a system that can assist me in such situations.
        Current implementations (radar cruise control, brake assist etc) are designed to engage only when the situation has become life-or-death, i.e. long after a competent driver would have taken action himself and changed the situation to non-lifethreatening. You're in control at all times, t

        • by bitrex ( 859228 )
          From a liability point of view, it's preferable for automobile manufacturers to have their vehicles only engage safety systems well after human reaction time has been taken out of the equation. If a car started implementing emergency braking, seat belt tightening, etc. while the vehicle still had positive human control one could both imagine and expect endless varieties of "the car made it happen" litigation that would have no target other than the manufacturer.
      • by mcgrew ( 92797 ) *

        As a programmer, I just don't trust computers enough to make life-or-death decisions for me.

        Um, you work at Microsoft, right? =)

        Because there IS non-buggy code out there. LASIK eye surgery would be impossible without the laser beams (that slice your eye's cornea) being controlled by computer. There are many other medical devices that are computer-controlled.

        Fighter aircraft are "fly by wire". So's the space shuttle.

        Fortunately for astronauts, fighter pilots, and LASIK patients you don't program these system

    • Re: (Score:2, Informative)

      by mcgrew ( 92797 ) *

      Having the car react automatically to the car in front saves the 1+ second reaction time of the human driver, making you less likely to rearend someone

      Not tailgating works, too. If you've ever rearended someone and your brakes worked, you're an idiot and should not be behind the wheel of an automobile.

      This is NOT technology for the city. The car should ONLY decellerate/brake without human assistance when the cruise control is on.

      Every time you brake, you turn momentum into heat. That momentum came from the

      • Every time you brake, you turn momentum into heat. That momentum came from the combustion of an expensive liquid that I, for one, do NOT like to waste, as my name's not Warren Buffett.

        My hybrid converts that momentum back into potential energy you insensitive clod!

    • by sker ( 467551 )

      "you could synchronize cars so they run at the same speed instead of harmonica-ing all the time (prevents traffic jams), etc."

      Perhaps my accordion will change your tune. How does traffic harmonica?

  • by cjhanson ( 1296897 ) on Thursday October 09, 2008 @03:13PM (#25318567)
    I've had the idea for a long time that the brake light system should be an LED array, which would get progressively brighter, or fill more area, or by rapid blinking, indicate the rate at which the driver is attempting to decelerate. An inch of light indicates "I'm slowing a little" and 6 inches of light indicates "I'm stopping now".

    Go ahead and patent this, Microsoft.
    LED by example. Get it? Okay I'll stop.
    • by mcgrew ( 92797 ) *

      LEDs aren't needed for that. Just use an old-fashioned bulb, and put a potentiometer or rheostat on the brake pedal.

      I can think of a few drawbacks, not the least of which is the brake light is supposed to get your attention.

    • Some cars have that. The brake light in the rear window will flash in patterns. The harder the press, the more lit bulbs vs dim bulbs in the pattern-- but when I was driving behind one of these cars for the first time, not knowing what it was, I thought it was some crazy sort of hazard light. I couldn't tell what the flashing meant at all. There would have to be some sort of standardization or public service announcement or people just won't understand what the hell is wrong with the car in front of them
  • This is a perfectly reasonable concept. It would be awesome if my car knew a few things about the car in front of it. If it was connected to it via an LED wireless network, then it could tell a few things about the next car, and the next, and the next. This would mean that minimum following distance was no longer constrained by human reaction speed, instead being limited more by the actual deceleration capabilities of the vehicle itself. A blowout in heavy traffic would no longer result in nine car pileu

    • A blowout in heavy traffic would no longer result in nine car pileups.

      Someone with an LED and malicious intent will do that for you now.

      • Nope, not at all. This system would be dependent upon already existing technology which could tell you how close the person in front of you is to them. The worst thing that would happen would be that they could artificially cause you to slow down when you don't need to. Just a small amount of that where their actual location doesn't match the information that it's broadcasting would result in the assumption that the information they're presenting isn't reliable. At that point, the car would revert to norm

  • Forget the network (Score:4, Interesting)

    by chord.wav ( 599850 ) on Thursday October 09, 2008 @03:22PM (#25318697) Journal
    Put two white leds in the rear bumper and a wiimote between the headlights of each car.
  • vision balls that are in my thought box.

    Above line stolen shamelessly from Jon Stewart, referring to his take on CNN's "perception analyzer" graph in the Presidential/VP Debates.

    Not that I disapprove, or anything. :D

  • by Anonymous Coward

    Erm, they should take a look at this:

    instead of re-researching it from scratch.
    And the project is opensource.


  • An interesting idea, stupid article, and even worse Slashdot summary. For those who couldn't read all 5 paragraphs of the article, the idea is that LEDs can be rapidly modulated, basically acting like an IR remote, only in the visible spectrum. And they can modulate so fast that it's imperceptible to the eye (AKA "vision ball")

    The brake light idea that the summary innaccurately mocks would actually allow the brakes in your car to be activated when your car "sees" the brake lights on the car in front of
  • For those of you unsatisfied with IP Datagrams on Avian Carriers (RFC 1149), we now have IP Datagrams on Aldis Lamp!
  • by cmholm ( 69081 ) <> on Thursday October 09, 2008 @04:35PM (#25320075) Homepage Journal

    I knew I had seen an led-based point-to-point networking system described somewhere, and after a few minutes on hackaday, here it is [], straight from 2005. Best part is, the linked to Ronja [] project is open, free speech-wise (and free beer for the major league scrounger).

  • LED Pay Phone Tap (Score:3, Interesting)

    by HTH NE1 ( 675604 ) on Thursday October 09, 2008 @04:48PM (#25320279)

    At the University of Nebraska at Lincoln, in the Student Union on the main campus (not East Campus), there is still a bank of pay telephones under one of which is a large metal box with a single LED on it, still there even after the remodel since I was a student there. One day between classes I observed someone using that particular pay phone and seeing the LED on that box alternately flickering in concert with the person's lips, then again presumably in sync with the sound coming from the other end of that call. I've long thought that if I converted that brightness pattern back to sound, I could listen to both ends of the conversation at a distance.

    And I also wondered what the purpose of that box truly was.

    • by Cerlyn ( 202990 )

      Having seen devices like these in the past, chances are it is a telecommunications device for the deaf [], in this case designed for payphones.

      I presume there would have been instructions printed on the front of the device that would go something like this: If a deaf or hard-of-hearing person wants to make a phone call, they insert coins, then dial the number of interest. When they see the light on the other end flashing randomly (i.e. not a ringing or busy signal), they can press a key on the payphone's t

  • Big Bro (Score:2, Insightful)

    by labnet ( 457441 )

    George Bush wet dream.
    Mandatory encoding of the cars VIN & speed into modulation of the cars parking led lights.
    Makes that big brother tracking just one step easier.

  • 802.11, anyone? (Score:2, Informative)

    by Anonymous Coward

    I recall that 802.11 contains a part that specifies using infrared for 1 and 2Mbit/s multipoint operation. Apparently since its inception in 1997. Getting a bit more bandwidth out of it would be nice though. And, uh, more implementations.

  • Inevitably there will be a backlash to this technology, similar to what occurred in response to Compact Digital Audio discs. It will be spearheaded not by audiophiles but by photophiles, who will insist that persistence of vision is a myth and that any strobing effect, even measured in millionths of a second, is dangerous and will cause mental illness or cancer.

    Mark my words....

  • Perfect! (Score:2, Insightful)

    by denmarkw00t ( 892627 )
    Personally, I'd use the vision balls that are in my thought box.

    Of course, because thats why those lights are there, so that your car can hopefully help in that .000000000001% chance situation where you aren't paying attention, back into a pylon, and crack your tail light. Not the worst thing, but an expense nonetheless - vs. some LEDs? Not bad, of course, the rest of the hardware...

    I dunno, didn't RTFA. My vision balls are dry and red.

Who goeth a-borrowing goeth a-sorrowing. -- Thomas Tusser