In-Car Algorithm Could Rapidly Dissolve Traffic Jams

  • Posted by a hidden member.
    Log in to view his profile

    Sep 15, 2011 6:34 PM GMT
    http://www.technologyreview.com/blog/arxiv/27166/?ref=rss

    If cars broadcast their speeds to other vehicles, a simple in-car algorithm could help dissolve traffic jams as soon as they occur, say computer scientists. [..]

    One interesting question is how best to dissolve jams once they form. Most traffic experts agree that the basic idea is to ensure that cars leave the jam more quickly than they arrive, so that the jam dissolves.

    Now Hyun Keun Lee and Beom Jun Kim at the University of Seoul in South Korea have a come up with a simple idea to automate and improve this dissolving process. They define two types of drivers: optimistic and defensive. Defensive drivers leave more room to the vehicle ahead than required by safety. Optimistic drivers leave too little.

    They then use a cellular automaton to model traffic flow in a way that reproduces most of the usual driving behaviours such as exceeding the speed limit, overreacting to road conditions by accelerating and braking to hard and so on.

    But they also add an extra ingredient. All the vehicles in this model share their speed and position with their neighbours and this information filters downstream. That means downstream vehicles immediately become aware that the traffic ahead has come to a standstill.

    When that happens, Lee and Kim's algorithm immediately switches all the downstream driving behaviour to defensive, so that vehicles exceed the safe distance between them. This slows the rate at which vehicles join the jam.

    At the same time, vehicles leaving the jams are made to accelerate away quickly using automated cruise control. This increases the rate at which vehicles leave the jam.

    The result is that the jam quickly dissolves.
  • Posted by a hidden member.
    Log in to view his profile

    Sep 15, 2011 7:33 PM GMT
    Where's my car that has GPS enabled auto-pilot (auto-drive) ?
  • Posted by a hidden member.
    Log in to view his profile

    Sep 15, 2011 7:36 PM GMT
    alphatrigger saidWhere's my car that has GPS enabled auto-pilot (auto-drive) ?


    I'll get peace in the middle east before this works.

    Do you want other cars controlling your speed?

    Course not. That would be scary/silly/stupid.

    A problem in my area, I believe, is congestion around exit ramps causes backups for miles on the interstates.

    What causes exit-ramp congestion?

    Traffic signals on side streets.

    Good luck on that;
  • Posted by a hidden member.
    Log in to view his profile

    Sep 15, 2011 8:18 PM GMT
    They use stop lights at the on-ramps that supposed to alleviate the traffic during rush hour. I guess it sort of helps. But I've been places that do fine without them.

    I think another issue is how they set up the exit ramps. They are too narrow! They give people 1 lane to exit off of and 6 lanes of traffic.

    Or they have an exit and an on ramp in the same lane only a few feet apart. Drives me nuts.
  • Posted by a hidden member.
    Log in to view his profile

    Sep 15, 2011 8:37 PM GMT
    MochaMuscle saidThey use stop lights at the on-ramps that supposed to alleviate the traffic during rush hour. I guess it sort of helps. But I've been places that do fine without them.

    I think another issue is how they set up the exit ramps. They are too narrow! They give people 1 lane to exit off of and 6 lanes of traffic.

    Or they have an exit and an on ramp in the same lane only a few feet apart. Drives me nuts.

    I support entrance ramp metering, those lights that constrict the flow during peak traffic times do help ease merging traffic.

    I was bemoaning that it seems like Seattle ran I-5 directly through downtown and all the congestion on the exit ramps interferes with smooth traffic flow.

    6 lanes of traffic. A big problem is regular interstate lanes are stop-n-go mode, so people get in carpool lanes. But, they can't get out of the carpool lane and get their exit without interrupting three to five lanes of traffic. Seattle drivers demonstrate this feat getting from carpool on the 405 southbound, cut across two lanes to reach westbound I-90.

    It screws up normal interstate traffic flow.

    Besides "slow traffic keep right,except to pass" is a clear invitation for hat wearers to block #1/Left/passing lanes anyway.

    Be careful when you wish for more lanes of interstate. Human nature will punch you in the balls...every time. Harshly.

  • Posted by a hidden member.
    Log in to view his profile

    Sep 15, 2011 9:09 PM GMT
    I live 1 mile from school and take the train to work.

    Only driving I do is to Costco or Target or to the mountains.

  • Posted by a hidden member.
    Log in to view his profile

    Sep 15, 2011 9:50 PM GMT
    alphatrigger saidWhere's my car that has GPS enabled auto-pilot (auto-drive) ?
    At the airport.
  • Posted by a hidden member.
    Log in to view his profile

    Sep 16, 2011 7:47 AM GMT
    There used to be a device offered here in the states that transmitted GPS/speed information to a central server, and in turn, it provided real time traffic conditions. Problem is that it didn't really catch on, and the company went under. My guess is that people didn't want to pay the monthly fee. But oh well.

    http://gizmodo.com/372736/dash-express-gps-full-drive-review-total-traffic-terminator

    Anyways, there's no solution to alleviate traffic. Because it all comes down to the driver. There are just way too many dipshit drivers that don't realize that THEY are the cause of traffic..

    - Talking/texting on cell phone
    - Cruising in left lane
    - Reading newspaper while driving
    - Putting on make-up
    - Watching movies
    - Making fruit smoothies

    9sIJd.jpg
  • Posted by a hidden member.
    Log in to view his profile

    Sep 16, 2011 8:41 AM GMT
    xrichx saidThere used to be a device offered here in the states that transmitted GPS/speed information to a central server, and in turn, it provided real time traffic conditions. Problem is that it didn't really catch on, and the company went under. My guess is that people didn't want to pay the monthly fee. But oh well.

    http://gizmodo.com/372736/dash-express-gps-full-drive-review-total-traffic-terminator


    OnStar's Turn-By-Turn navigation package offers this feature if you're subscribe to the service. Simply press the OnStar blue button and say the commands to get real time traffic and the automated adviser will give you almost accurate informatio if EMS, and LEA are already aware of it.
  • Posted by a hidden member.
    Log in to view his profile

    Sep 18, 2011 2:46 PM GMT
    driving 15-20 under the speed limit for no reason also makes massive traffic.