Automation of unmanned railway gates!

Discussion in 'The Projects Forum' started by hamza, Nov 5, 2008.

  1. hamza

    Thread Starter New Member

    Feb 8, 2007
    im starting work on a system in which the un-attended railway gates would get automated... the idea is, that wen the coming train would reach a certain point before the gate, some sensor would sense it, and the gate would shut down. and wen the train passes ahead, it would b detected by another sensor which would once again open the closed gate.. now can someone help me chose a better sensor?? which kind of sensors shoud i use?? ... i thought of using IR sensors, or LASER.. but someone told me that they both won't work properly.. im very new to this "automation" thing.. i need help in chosing a better sensor...

    looking forward to ur advises. :)
  2. mik3

    Senior Member

    Feb 4, 2008
    Is that a serious project for a company or just for demonstration?
  3. steveb

    Senior Member

    Jul 3, 2008
    Did they say why they wouldn't work? Also, how were you planning to use these two devices? The method is important.

    A laser could have problems in fog or rain or snow conditions.

    What kind of reliablity is needed? Is there a backup system in place in case this one fails?
  4. KL7AJ

    Senior Member

    Nov 4, 2008

    Well, before you go reinventing the wheel, see how it's been done for the past 100 years. Block signalling with supervisory rail currents has been EXTREMELY reliable.

    #1 rule of electronics....."If it ain't broke, don't fix it."

    (Unless you really want to!)

  5. hamza

    Thread Starter New Member

    Feb 8, 2007
    im making my final year project at undergrad level.. this "gate closing and opening on detection" thing, is one part.. the other part is, that wen the train leaves a certain train station, an automated gsm based txt message will be sent to the next train station that the train has left and it will take a certain amount of time to reach.. (assuming that it would be travelling at a constant speed... i hvnt come up with anything to calculate the exact time actually) moreover, the idea is to run this whole system on solar power..

    im in Pakistan and here we dnt hv any previous such systems installed in real life application.. this is jst goin to be a demonstration. so its very new..

    yes fog and other weather conditions might be the problem that IR or LASER wont be suitable...

    any other, more robust detector?? wot else can i use instead of IR... ??

    thank u so much for rplying to my post :)
    any other idea or advise to make this final year project would b of so much help aswell
  6. beenthere

    Retired Moderator

    Apr 20, 2004
  7. hamza

    Thread Starter New Member

    Feb 8, 2007
    thanks for that, but that article in wikipedia reffers to signalling systems... not crossings...

    moreover, i asked wot kind of other sensing devicies i could use other than the IR...? can a distance sensor work? wot type?? or the sensor which the Line follower robot uses (i dnt know wot its called) ??? could someone help me on that plz.. wot type of sensors could i use!
  8. RiJoRI

    Well-Known Member

    Aug 15, 2007
    There are sensors that get placed in or near driveways that detect the metal of an automobile passing by, and this signal is used to alert the homeowner that someone is coming. I would use a couple of these sensors spaced 20 or so feet (~7 meters) apart to detect the presence of a train. Use two sensors because sometimes the train may stop, with the area between cars near your sensor, and give a false "Train has passed" signal. The two signals should be combined and when a train is detected, the gate goes down.

    There should be another set of sensors to raise the gate when the train has passed.

    The logic is left as an exercise for the student.

  9. floomdoggle

    Senior Member

    Sep 1, 2008
    Try a pressure sensor.
  10. beenthere

    Retired Moderator

    Apr 20, 2004
    Please to note the Wikipedia article on RR grade crossings. Pay particular attention to the mention of the track circuit.

    Of course, you might think of something more reliable and robust than the railroads have...
  11. oned

    New Member

    Jan 27, 2009
    i think you can used magnatic sensor.. this sensor can sence metal.