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Traffic Light Control For The Masses

uniformed1 writes "Eliminating red lights along the routes of their vehicles can give emergency response teams the few extra critical minutes that can save lives and property. A front page article in today's Detroit News details the emerging problem with a device that is now being made available to the public -- a traffic light changer. Originally intended only for emergency vehicles, the $300 MIRT (mobile infrared transmitter) emits an infrared beam that signals traffic signals to turn green and gives the vehicle the right-of-way. It is only a matter of time before self-centered drivers start using the devices widely to skirt traffic congestion, which is creating fears that chaos will ensue." Maybe if everyone had these, it would lead to smarter intersections.

57 of 824 comments (clear)

  1. No Encryption keys? by HermanAB · · Score: 5, Insightful

    What idiots make these things???

    --
    Oh well, what the hell...
    1. Re:No Encryption keys? by shird · · Score: 4, Insightful

      that would require a challenge-response type system. Thus, it would have to be a transmitter and reciever with processor etc, rather than just blindly transmitting all the time.

      A lot more difficult to develop, a lot less fault tolerant.

      I guess it could just digitally sign todays date with a secret key and transmit that or something. However, eventually the key would be leaked or reverse engineered. Basically, if you are going to give the 'key' (the little box which does the transmitting) to anyone, then eventually that key will be figured out. No amount of encryption can avoid that. (Although tamperproof smart card type devices are a good start).

      --
      I.O.U One Sig.
    2. Re:No Encryption keys? by wfberg · · Score: 3, Insightful

      I guess it could just digitally sign todays date with a secret key and transmit that or something.

      You've got the right idea!

      However, eventually the key would be leaked or reverse engineered.

      The fun thing about keys is, you can have as many keys as you have mirt boxes - one goes missing, you remove the key from the receivers.

      --
      SCO employee? Check out the bounty
    3. Re:No Encryption keys? by Perrin-GoldenEyes · · Score: 4, Insightful

      Do you network all the boxes and just broadcast a remove code? And what do you do when some l33t hax0r starts sending his, unofficial, broadcasts on that network?

      Then the emergency vehicles run the same way we do in places where we don't have those systems. We run red lights (legally) with lights and sirens on, but we do it carefully. It might take a little bit longer to get where they're going, but it's not a catastrophic failure.

      BTW, if you're wondering about my use of "we", I'm a Maryland EMT.

      --
      -Perrin.
      Now I want you to go in that bag and find my lightsaber. It's the one that says bad mother-fscker on it.
    4. Re:No Encryption keys? by Dolly_Llama · · Score: 4, Insightful

      Isn't the simplest method to simply flash the red-light camera at whoever uses the device and send big fat nasty tickets to those caught doing it fraudulently?

      --

      Somewhere, something incredible is waiting to be known. -- Carl Sagan

    5. Re:No Encryption keys? by Nogami_Saeko · · Score: 4, Informative

      Wouldn't work if it was done right.

      I use an infrared remote to access my condo - it uses an infrared remote system that's fairly simple, yet effective:

      -The remote (much like garage door openers) uses a rolling pseudo-random number sequence. The remote generates a code based on the next number in sequence from a random number generator seeded with a known key for that particular remote (the main controller needs to be "paired" with the remote before use so it knows what seed each remote is using).

      -The controller keeps track of all of the remotes for the building and pre-computes the next 256 valid codes that each remote will generate based on the seed exchanged when the remote is paired.

      When a remote triggers, it sends the random number code (NOT the key) by way of infrared to the controller receiver. The controller checks to see if the number the remote transmitted is in the next 256 valid numbers for that particular remote, if so, you get in. If not, you don't and the attempt is logged.

      If you press the button more than 256 times (playing with the remote button for example) when you're not around the sensor, none of the precompute codes will match the next time the remote is used and it will be useless until re-paired.

      Even if you capture the code being sent from the remote, you won't know the key that the random number generator is using in that particular remote to generate the number sequence, or any of the subsequent numbers that the remote would generate. You'd only capture the code that was sent, and once that was used, it wouldn't work again anyway.

      If a remote key is compromised, it's simple to simply deactivate that particular remote key. If the system is brute-force attacked, it can either deactivate the sensor that's being attacked, or just call security to the appropriate location.

      N.

      --
      "Nothing strengthens authority so much as silence." - Charles de Gaulle
    6. Re:No Encryption keys? by crucini · · Score: 3, Interesting

      Well, police departments, or rather their vendors, already face these issues for encrypted radios. Typically a fixed key is used for a large group of radios for a period of time, loaded via a key loader box. Some systems allow OTAR - over the air rekey, where the new key is encrypted with (I think) the old key and broadcast.

      This problem is a little harder because an attacker could steal either the traffic light equipment or the vehicle equipment. The traffic light equipment is probably more numerous and vulnerable. Public Key crypto would be very useful here, because then stealing the receiver doesn't help you impersonate the transmitter. Unfortunately, it probably needs too many bits for the IR strobe carrier. So unless we "cheat" with a supplemental data channel or something, there's no good solution.

      Although - you could have an operational key (symmetric) and a rekey key (public key). The rekey box is guarded like the crown jewels. Once a month, or if the operational key is known to be compromised, you bolt the rekey box to the roof of a police car and drive slowly around town, pausing 60 seconds or so at each light. Enough time for the slow public-key transmission. Then you rekey all the vehicle units off the rekey box. Could work.

  2. Here's a link to a place that makes them... by mikeylebeau · · Score: 5, Informative

    www.themirt.com has a lot of info on these devices. Even a dealer list of where to get one. Man, I'm tempted...

    -mikey

    1. Re:Here's a link to a place that makes them... by Lumpy · · Score: 4, Informative

      go for it and buy it.

      Oh, and I don't want to be you when the cops pull you over. In Chicago it's a $4000.00 fine and 30 days in jail.

      They are easily detected, they blast a massive floodlight of IR.

      I welcome every complete moron that buy's these to use them... just like the police radar jammers.

      --
      Do not look at laser with remaining good eye.
    2. Re:Here's a link to a place that makes them... by Lord+Kano · · Score: 5, Insightful

      I welcome every complete moron that buy's these to use them... just like the police radar jammers.

      As with any device that is in a legal grey area, judicious use is the key. Think of these things like stinkbombs in high school. If you are the ONLY one in the room where you use it, it will be more than obvious who is responsible. If you do use it in an auditorium with 500 other students around you, it is much harder to find out who is the culprit.

      If you are in a fair sized group of cars, you are pretty safe when using a radar jammer or device to change the traffic signal. Sure it may be illegal, but when the effort required to catch you makes in impractical to do so, the police don't even make the effort. How often does the office football pool get busted?

      LK

      --
      "Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
  3. Change the Behavior by Dolohov · · Score: 4, Interesting

    One thing to do, then, would be to change the behavior of the traffic lights so that on receiving this signal, they go to four-way red. Since emergency vehicles can run red lights, it doesn't stop them, while simultaneously deterring civilians from using them.

    (The trouble is the lack of feedback. You'd need some kind of indication that the other ways had gone to red before the ambulance driver will have confidence going through the intersection at full speed)

    1. Re:Change the Behavior by Yottabyte84 · · Score: 3, Insightful

      You drive on the left side of the road, around them.

    2. Re:Change the Behavior by bluGill · · Score: 4, Interesting

      All the lights I've seen have a light next to the recieving unit that indicates which direction has the right away. This was done after 2 emergency vechicals going different directions (or at least coming from different directions) crashed in the middle of the intersection because they assumed they had the right away.

    3. Re:Change the Behavior by Jah-Wren+Ryel · · Score: 4, Informative

      In most cities, the light goes green for the guy with the transmitter, but a white strobe light on the same pole goes off too. If all lights went red, but the strobe still went off, the should be enough to make the driver confident that all directions are indeed red.

      --
      When information is power, privacy is freedom.
    4. Re:Change the Behavior by Izago909 · · Score: 5, Insightful

      The lights in the direction of the emergency vehicle turn green so people can move out and away instead of blocking the intersection. I've seen people at regular 'dumb' intersections sit in front of a fire truck and block it because he thought he would get in trouble for running a red to let them through. Also, I'm not sure if it's lke this everywhere, but around here if something comes through such an intersection the light goes from green to red with no yellow warning at the exact same time the other direction gets the green. That sould defiately cause some chaos if ignorant drivers decide to get selfish.

      One thing people always forget is that speeding and runing reds rarely gets you there faster. People who dodge and weave through rush hour highway traffic are a whole 2 or 3 cars in front of me when I get to the off ramp. I've learned the timing of lights around my office and home so now I can actually get there faster by driving just few miles under the limit. Usually it's the impatient people that create traffic in the first place. The more that people obey speed limits the better the timing of intersections gets.

  4. Easy solution... by Realistic_Dragon · · Score: 5, Funny

    IR guided Maverick anti tank missiles mounted on traffic light poles. Bet those suckers shut off their IR transmitter then!

    --
    Beep beep.
  5. Illegal? by marshac · · Score: 3, Insightful

    Why are these devices not illegal? Seems to me that the intersection should take a picture of the vehicle using the device... if there aren't flashing lights, send a ticket in the mail.

    Once people know that they will be fined, they will stop using it. If you can't deal with red lights, then don't drive.... it's part of the agreement that we all agree to live by when driving (aka "the law"). These rules are there to make driving safer for everyone.

    1. Re:Illegal? by nacturation · · Score: 5, Insightful

      Why are these devices not illegal? Seems to me that the intersection should take a picture of the vehicle using the device... if there aren't flashing lights, send a ticket in the mail.

      The only problem there is how do you know which driver among the 20 approaching the intersection has the device? Sure, if you see someone with their arm out the window pointing a remote at the traffic light it's a no-brainer, but an IR transmitter peeking out of the front grill or behind some trinket on the dash would be impossible to make out.

      Just make it some enourmous fine... $25000 per offense or some such figure when the device is used for a non-emergency purpose. That way, the devices themselves aren't illegal (though I agree that they probably should be) but the uses are. You could, conceivably, drive your wife to the hospital when she's about to give birth, but you couldn't use it just because you're late for work.

      --
      Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
    2. Re:Illegal? by marshac · · Score: 5, Informative

      your average CCD will detect IR. Don't believe me? Pull out your camcorder and aim a remote at the camcorder. It looks like white light. I know where I live, we have CCD DOT cams at almost every intersection. It would be easy to pick out the car emitting the bright flashes.

  6. Lame by Midnight+Warrior · · Score: 3, Interesting

    The specs have been out on how to build these things for years. Never caught on, maybe because they felt like the whole beige/black/red/blue box phenomenon. MAYBE if they start showing up in places like Best Buy it will catch on, but even still, I doubt it. Besides, I asked some EMTs/the driver one time if the light at the intersections would benefit them by this light predetermination technology. They said no. Doesn't matter because people still run the yellow and red lights so they still have to slow down. And this was for a signal 100 ft. from the station driveway.

    I concede that yes, it may help in congested downtown areas like LA or NY, but in 95% of the U.S. they either aren't installed or useful enough to justify their cost.

    BTW, it's just a pre-canned, encoded signal on a fixed carrier wave over an infrared signal. Think "really powerful remote control" for you newbies.

  7. Obligatory Simpsons reference by bartyboy · · Score: 4, Funny

    Professor Frink: "We studied traffic patterns and found that drivers move the fastest through yellow lights, so now we just have the red and yellow lights, mm-haiai."

    Lenny [flooring it]: "Stay yellow! Stay yellow!"

  8. Ambulance drivers don't go full speed by JohnQPublic · · Score: 5, Insightful

    The only time an ambulance driver goes full-speed through an intersection with the siren screaming and cars breaking left and right is in the movies. In real life, they slow down and approach the intersection with all the care appropriate to one who's about to violate the traffic pattern. Because, after all, it doesn't help the dying guy in the back if the ambulance gets in an accident on the way to the ER.

    1. Re:Ambulance drivers don't go full speed by Avenger · · Score: 5, Interesting

      OK, a few things here (and yes I have experience wiht this, only not with an ambulance, but with a fire truck, however the concepts are still the same.)

      First off if the ambulance driver is any good, he/she does not go full speed through a green light, or a red light, or a yellow light for that matter. If they are really good, they stop and make sure they have the right of way. Believe it or not, in most cases that have made it to court where an accident occured between a civilian and a emergency vehicle, the Emergency Vehicle driver was held accountable. This is true even in the case where the Ambulance had a green light to go and the ambulance was struck BY the civilian running a red light. (I don't remember the specific case but was taught to us when we took our driving course.) Personally I stop at every light, green or not and make sure that I have EVERYONES attention before going through an intersection. It is better to get my truck, and my fellow fire fighters there in one piece than to crash the truck and not get there at all.

      Another interesting point of fact, (at least in New York state) the flashing red lights give NO legal rights to disobey the speed limit. This is something I allways try and keep in mind, because you do kind of feel invincible when you are driving those big red trucks.

      --
      Of all the things I miss .... I miss my Mind the ...... ummmmmm what is that word.
    2. Re:Ambulance drivers don't go full speed by Rorschach1 · · Score: 3, Insightful

      Exactly. I know that at least around here, the ambulance company policy REQUIRES that all ambulances come to a complete stop at all red lights.

      You know what's REALLY irritating, though? When you pull up to a red light with the lights and siren going, and some idiot sees you stop and decides it's their turn to go.

      Yes, I'm a nerd AND an EMT...

  9. Re:"Maybe if everyone had these, it would lead..." by Theatetus · · Score: 4, Insightful

    I think the idea was that mass dueling transmitters might be smarter than weight sensors or cameras. I see this, however, as a perfect case study for the Tragedy of the Commons.

    --
    All's true that is mistrusted
  10. Re:Once again, Slashdot trumps logic for technolog by cgranade · · Score: 3, Funny

    Um... if it has a range of 1500 ft., people would activate it at 1500 ft, it would get trumped at 1499 ft, so they'd activate it at 1498 ft... you get the picture. In short, there'd be two people hurdling toward each other, hoping that the light would stay on their side.

    --

    #define DRM chmod 000

  11. Easy enough to catch by ArsonPanda · · Score: 4, Funny

    1. There's an awfull lot of cameras at intersections these days. (and not just red light still cameras either, where I am there's a few vid cams at every major intersection).

    2. IR shows up on B&W CCD cameras.

    1+2 = just have someone watch vids for cars that have bright IR pulses coming from the dash.

    3 ????

    4. Profit

    --

    --I don't want the world, I just want your half.
  12. We have light-sensitive systems in the UK by jo_ham · · Score: 5, Interesting

    There are sensors on the top of traffic lights in the UK that respond to headlights.

    If an ambulance is approaching lights on red he can flash his full beams a few times and the sequence changes.

    I use this feature all the time at the lights near my house, especially late at night when the deafult sequence on the lights is to stay green for the main road all the time unless a car approaches on the minor road.

  13. Rarely used by bobthemuse · · Score: 3, Informative

    I've worked for several ambulance companies and spent a good amount of times in cities on the east coast, and I have never seen an ambulance with this device installed.

    On top of that, traffic regulations technically require ambulances to stop at red lights and proceed through after the've verified that traffic is stopped. I think the siren would be more effective than a sudden red light.

    Maybe I can see a use for turning it green, as it would help get the traffic in front out of the way, give them space to pull over, but for this to work, they'd have to activate it from a distance. Since IR isn't focused like a laser, I doubt it would work from a great distance.

    1. Re:Rarely used by thebigmacd · · Score: 4, Insightful
  14. Could this be the a classic Chrome Box? by EMIce · · Score: 4, Informative

    I guess the slashdot editors editors weren't too into the hacking/phreaking scene back in the day. This was documented some 10 years ago.

    If you want proof, consult the google time machine. Scroll down or search for "Chrome Box".

    1. Re:Could this be the a classic Chrome Box? by GeorgeH · · Score: 3, Funny

      Yeah, I was trying to figure out if this was Slashdot in 2003 or 2600 in 1994. Damn daylight savings time, what with the screwing up of the time and the glaven

      --
      Why can't I moderate something "Wrong" or at least "Grossly Misinformed"?
  15. More info about optocom sensors by NetMasta10bt · · Score: 4, Informative

    Here is some more information with pictures of the Optocom sensors (mounted to the signals) and of EMS and Fire transmission units.

  16. One legit use I can think of by finkployd · · Score: 3, Insightful

    Motorcycles. Generally I cannot trigger a light change to save my life, so I sit there like an idiot waiting for a car to come up behind me and hopefully get close enough to trigger it for me. Especially annoying at intersections where one must wait for a green arrow to turn left. Still though, I do not believe that is enough of a problem to warrant the general public getting these.

    The idea of non emergency people having these is insane. And you know it is going to be the H2 driving, cell phone yapping, news paper reading, oblivious to the world around them group that will absolutly HAVE to have these. I mean my god, I have to get to my office to start on today's fancy bookeeping and intern bonking, RIGHT THIS MINUTE! Damn all these plebes and their "right of way" nonsense, can't they see I'm more important?

    Damn I'm bitter today.

    Finkployd

  17. Re:Plans? by Micro$will · · Score: 4, Informative

    I assume the old ones where nothing more than an infared flashlight, and the "upgraded" ones use some sort of modulation something like a TV remote. The picture in the article shows what looks like a 3rd brake light with a lighter plug. It probably costs $20. They're basically charging $300-$500 for a long range TV remote control

  18. *sigh* by Guppy06 · · Score: 3, Interesting

    "Maybe if everyone had these, it would lead to smarter intersections."

    Maybe if everybody drove the speed limit they'd synchronize with the timers in the traffic lights and not get stopped by a red light to begin with.

    (It also provides the enjoyment of sailing past the Honda weed-eaters, the ones that just had to hurry up and beat everybody else to the next red light.)

  19. Alternate method by r00t3r · · Score: 5, Funny

    It might be easier to change the light by getting out and pressing the walk button on the sidewalk.

  20. Mostly unnecessary in California by StandardCell · · Score: 4, Interesting

    Although I lived almost three years in Northern California and disliked the place as a whole, the one thing that did stand out is the outstanding traffic control system with optical and pavement vehicle sensors. The volume of traffic notwithstanding, it was the fairest traffic systems I've ever seen.

    For example, if there are left turn lanes on opposing lanes at an intersection, and one of those lanes is empty but the other is full, when the lights turn green the left turn lane for the empty lane stays red and simultaneously turn the signal green for opposing straight-through traffic. Not only that, but the left turn signal would only stay green until the last car had cleared or until a maximum time interval elapsed, at which point it would turn red again and allow opposing straight-through traffic to flow. In fact, if there was no waiting straight-through traffic in the one direction, some lights would just stay green for the lanes that had it until a car attempting to cross the intersection would trigger a timer.

    Contrast this with, say, Edmonton, Alberta's dreadful traffic system, where nearly everything is on straight timers save for buses with road sensors and emergency vehicles, and there are no timing lights for freeway on-ramps. There are some sensors at some intersections, but by and large nearly everything is timed and it creates frustration and accidents. It's doubly ironic considering that Edmonton has the highest density of traffic lights in North America and traffic circles on major roadways!

    In other words, if you design your traffic system the right way the first time, devices like this become unnecessary. An economist once commented that traffic lights are a nearly perfect unbiased system for resolving conflict. Why create bias in favor of certain selfish individuals? It doesn't work in economies, and it doesn't work on roadways.

  21. Come on, fellow libertarians! by MillionthMonkey · · Score: 5, Funny

    We're going to hear a lot of people calling to make these devices illegal- except in the hands of qualified emergency response personnel. We must resist them. Traffic light control is yet another prime target for deregulation and privatization, and keeping these wonderful devices out of the hands of ordinary citizens restricts our liberty to control intersections that we've paid for with our tax dollars.

    Competition and free markets make everything better. They work great for companies, which is a strong indicator that they improve everything else, too- like public schools, the electrical power grid, and traffic lights at intersections. Why should emergency response vehicles receive a government-granted monopoly on the control of traffic lights? This is just old-fashioned, socialist thinking. If I want to turn my light green and yours red, and I'm willing to pay money for the privilege, why shouldn't I get the right of way? I've got more discretionary income, which means my time is probably more important than yours anyway. Government should not be standing on our necks and telling us who can and can't control traffic lights. The "invisible hand" can do a better job of guiding traffic through intersections anyway!

    I can hear the socialists whining even now. "But what about the poor ambulance and police cars?" they'll say. They're so addicted to government regulation they don't realize how wonderful things would be if it were every man for himself. Hey, why should the government have a monopoly on ambulance service and law enforcement? My Expedition has plenty of room in the back for a heart attack victim or a criminal. If I'm willing to pay the money I should be able to offer a competing emergency response service as I sail through an endless sea of green lights and yap on my cellphone. To argue otherwise is socialist, and we've learned from the fall of the Soviet Union that socialism doesn't work, people.

    OK, so it's a cheap shot at you guys. I can't resist- it's so much fun, and you make it so easy!

  22. Lame by xpccx · · Score: 4, Insightful
    "We'll probably try to avoid (selling to the public) if it may cause problems in the future," said Pregler, whose company is named Vision Aerodynamics.
    So what are they going to do, wait until ambulances or fire trucks can't get to their destinations before making a determined effort not to sell to the public? It's a little late at that point, no?
  23. Some interesting tid-bits: by niko9 · · Score: 4, Interesting

    Here are some of the vehicle traffic laws as they pertain to emergency vehicles here in New York State, other states are mostly similar.

    Only police department vehicles are allowed to proceed through red lights without stoping.

    EMS and Fire trucks have to make a full stop at every red light while going lights and sirens to a job, regardless of the priority.
    In reality, I slow down significantly and roll through at a cool 3-5mph.

    Lights and sirens for EMS and fire are a courtsesy. The guy in front of you is in now way obligated to blow a red light for you if he feels it's unsafe for him to proceed. Oh, and btw, if a medic or emt gets on the P.A. and tells you to cross a red light, and you get into and accident, the medic is at fault for the acccident.

    Going down one way streets and driving on the opposite side of the road are allowed, with the understanding that you do so at reduced speed and with extreme caution, any accident in this situation is all on your shoulders.

    Here in Manhattan, slow and steady is the best way. You can't justify injuring bystanders for someone who is already sick.
    And with critical patients in the back, you'll drive even slower to the hospital 'cause there's alot of things that we need to that can't be done if you're bouncing around the back cab like a virgin's first visit to some Panamanian wha wha rumphouse.

    These device have been mentioned here in the city, and it was agreed that it would cuase more confusion and possibly more liability for the city than it's worth.

    --

  24. Saw one years ago by Anonymous Coward · · Score: 3, Interesting
    I guy I know built one of these devices several years ago. It had abourt 100 IR LEDs in it. He's open his sunroof and point it towards an interection. I was in his car once for a ride when he had it.

    First, it didn't always work. Those sensors are positioned to see the pulsing signal from a light on top of a tall vehicle, like an ambulance or fire truck. He had an ordinary car which meant it was a lot lower than it should be. The sensors seem to have a cone-shaped sensitive area which obviously narrows you approach the intersection. So as he got closer to the intersection, where the weaker light might have a chance, he'd usually be outside the sensitive cone shape.

    Second, it was hard to tell when it was working. We did get what seemed like an unusually large number of green lights... but it was hard to tell if the "go box" was triggering them, or if we were just getting lucky. In several cases, traffic was also flowing through the intersection the other way which meant it hadn't done anything. Apparantly, the lights turn red in all other directions.

    However, we did approach one intersection where there was absolutely no doubt it worked. The light was green, turned yellow, and then turned green again. That absolutely never happens under normal circumstances, and when I saw that I knew it did indeed do something. This interection was approaching the crest of a small hill, and it was complex with five streets (one at a funny angle). As we got closer, the light must have bounced off something else, because the obviously unnatural green light we got turned yellow briefly and then red. I don't know what the drivers saw in the other four directions approaching the interestion, but they must have seen something equally strange, because we sat there for a LONG time as did the cars in coming from the other directions. NOBODY was willing to drive into that interestion, because it was obvious to all the cars that the light was screwed up somehow. That's something that virtually never happens. Traffic lights are incredibly reliable (must not be running Microsoft's products). And when confronted with a screwed up light, nobody was willing to be the first to risk driving into the intersection, even as the controller recovered and started it normal sequence giving green lights. After about 10 minutes, people started to believe a green really was safe and we got to move forward. This was during rush hour on a very busy 4-lane road... so it must have caused quite a bit of traffic backup.

    Anyway, my friend's "go box" (as he called it) eventually stopped working. It was home made and it used massive power to turn on those LEDs. They were probably running many times over their rated current. He couldn't turn the switch on too long or it'd blow the fuse to his cigarette lighter. Apparantly he'd replaced the normal fuse with 30 amps which allowed it to run for a minute or so. The wires and everything else about it got really hot. So it's no wonder it stopped working after a while. He talked a few times about building a bigger and better one... but ultimately it was not worth the effort. It couldn't reliably trigger most of the lights. He had many other stories of turning a light green and being stuck behind someone who'd just stopped and wasn't paying attention to the light because it wasn't expected to turn green again for a while. He used to joke "you really also need the lights and siren to make the other cars get out of your way".

    Posting anonymously for obvious reasons...

  25. detection and prevention by pair-a-noyd · · Score: 5, Insightful

    1. Do what the military does, strobe the lights in a morse code fashion. Assign a seperate code to each city vehicle that needs to use the system. Any vehicle not strobing a proper code gets no joy.

    2. retrofit traffic light camera's to snap pictures of the traffic when the system is activated. Remove the infrared filter from the camera and the camera will easily and plainly show the vehicle that is attempting to open the intersection. You get a picture of the perp and his license plate, plus the light will be plainly visible to the camera. Perfect evidence for a court case.

    If the system is coded and someone attempts to copy the codes then they can prosecute them for hacking into a governemnt computer system.
    After all, the traffic lights are computer controlled, they should not be accessible to the public and if you hacked the system via the Internet it would be your nuts on the chopping block.

  26. Make "Red Light" for all directions.. by Dr_Marvin_Monroe · · Score: 4, Insightful

    That's how I've heard this system operates (at least in Seattle)...strobe light gives "all-stop" at the signal. From where I heard this, it was done deliberately to avoid this type of stunt with the strobe light on civilian vehicles. This is also the safest option too, as emergency vehicles are trained to run red lights (after slowing and checking) and go around stopped vehicles. "All Red" also gives the emergency vehicles the clearance to use the opposing lanes and any other clear space in the intersection etc, coupled with the fact that at any intersection, you ONLY want the emergency vehicles moving...no others.

    Any system that creates "green" for the person with the strobe is, in my opinion, an inherently dangerous system. It encourages people to try this kind of stuff and makes people think that the ambulance or fire-engine behind them "won't mind if I go through too". The more moving vehicles there are, even if they're with the flow of the emergency traffic, the more dangerous.

    I can't imagine this system staying like it is for too long.

    How about tracking the emergency vehicles through GPS, then having the central traffic computers switch the lights around the emergency vehicle (far ahead) in such a way as to clear the path 2 blocks away and keep all opposing traffic off the intended path. For instance, lanes turning away from the path would be allowed to turn green so the vehicles could clear the area, lanes crossing would be halted 1 or 2 blocks away, and lights behind the emergency vehicle would stay red for some reasonable period of time to keep the lawyers a reasonable distance from the ambulances...most people wouldn't even see the emergency vehicles, as they would be sitting at a red light 1 or 2 blocks away, or simply shunted away from the path, and the ambulance/fire-truck driver would not even have to contend with stopped or moving traffic.

    This isn't too much to put on one of those little PLC traffic computers, and it would be a lot better than "strobe light gets the green" solution that these people thought up.

  27. Outdated by b1ng0 · · Score: 3, Informative

    Most traffic light sensors these days use a combination of infrared and visible light strobes, as well as encryption, to signal the light to change. These infrared emitters wouldn't do anything . Check out 3m Opticom system for more information.

  28. Re:Plans? by Davak · · Score: 4, Funny

    This will probably been the next gadget added to the Swiss Army PDA/phone combos.

    Before long will see those soccer moms with 3 kids in the back of her gas-guzzler pointing her cell phone at the light in between breaths of talking to her friends from the social club.

    Life is so unfair. :)

  29. Opticom by san+diego+codepig · · Score: 5, Informative

    The traffic light control system itself is called Opticom . It is patented and manufactured by 3M.

    It operates using very short pulses of light (< 10uS) occuring at a precise frequency (usually crystal controlled). The normal pulse rate is about 10Hz. An optional rate of around 12.5Hz can be used to give priority to other vehicles (ex. ambulance vs firetruck).

    The system is configurable and normally set to give a green light to the emergency vehicle (helping to clear traffic) but it can also be set to go red in all directions.

  30. Re:Plans? by zcat_NZ · · Score: 5, Insightful

    PROBLEM; Light goes green.

    Design the device to make the lights go RED in all directions. Emergency vehicles can safely drive around the waiting traffic on the 'wrong' side of the road, because there's no oncoming traffic. There's no 'subtle' way for a non-emergency vehicle to use this type of device.

    --
    455fe10422ca29c4933f95052b792ab2
  31. Re:Plans? by bubbazanetti · · Score: 4, Funny

    Obviously you have never driven in Louisiana...red light means hurry up.

  32. Re:Plans? by pi+eater · · Score: 4, Funny

    yesss i'm building one in my basement right now.

    gonna bet my gf a bj that there are no red lights on our drive home tomorrow.

    wish me luck!

    geek gear

  33. Except that... by phorm · · Score: 4, Insightful

    Emergency vehicles are still required to stop on a Red, then proceed. Stopping at each red light before proceeding shaves off seconds, and in the case of life-threatening injuring those few seconds could be crucial.

    I'd say that it should be very, very illegal for normal people to have these devices, perhaps you could give certain traffic lights a camera that snaps the license of whomever flashed it the "green" signal, therefore determining whom is making unauthorized use of the system

  34. What's Wrong with Just Jumping the Lights? by gilgongo · · Score: 3, Insightful

    Why have lights you can override at all? Why don't the emergency services just jump the lights like they do in the UK?

    If I come up to a red light, I'm stopping. If I hear an ambulance behind me, I expect it to jump the lights! The poeple on the green lane hear the ambulance and stop/slow down too.

    Works fine over here. Is there something special about US traffic?

    --
    "And the meaning of words; when they cease to function; when will it start worrying you?"
  35. Re:Once again, Slashdot trumps logic for technolog by Kymermosst · · Score: 3, Informative

    Also, it solves the problems motorcycles have with being too light to trigger the pavement sensor.

    You may have to explain this one... too light?

    The system used here works the same as a metal detector. A wire loop is embedded in the pavement (and it's not that difficult of a process you cut, insert the loop, and tar-seal) and it simply detects metal near the loop (because it changes the resonant frequency of the inductor). I've got two friends that ride motorcycles and they say it has never been a problem for them.

    --
    "Alcohol, Tobacco, Firearms, and Explosives" should be a convenience store, not a government agency.
  36. You're forgetting one detail... by CrystalFalcon · · Score: 3, Insightful

    "All Red" also gives the emergency vehicles the clearance to use the opposing lanes and any other clear space in the intersection etc, coupled with the fact that at any intersection, you ONLY want the emergency vehicles moving...no others.

    Actually, you DO want other vehicles moving. Specifically, the ones in front of the emergency vehicle. There's not always room to pull over or give way within your lane, and giving the vehicles immediately in front of you a red light will... well... stop you too.

  37. What about a free market by Rhys_Lewis · · Score: 3, Interesting

    Why not have a system where you pay as much as you like to whoever fixes/controls/maintains your local roads. You would have a box on your car that wirelessly beamed your ID number to traffic lights as you came up to them. If you were the only person at the intersection with a box, you would 'win'. If there were two people, then the one with the highest balance would win, if there were three, it would be the combined balances of the two going in one direction etc. And whatever money you donated would be reduced by 1/365 each day.

    All the money gathered would be put back into road maintenance/improvement.

  38. No soup for you! by Awptimus+Prime · · Score: 3, Funny


    Too late, I just submitted a pantent on that technology. You may continue your research upon purchasing a license.

  39. Re:Plans? by gfxguy · · Score: 4, Funny

    Don't worry, some day maybe you'll be able to afford a gas guzzler and join a social club, too.

    --
    Stupid sexy Flanders.