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British Rail Moving Forward with Sat-Nav/GPS

Posted by Zonk on from the need-that-for-my-bicycle dept.

de1orean writes "The BBC is reporting that after a successful limited trial using GPS satellite navigation to improve train safety and efficiency, British Rail is committed to instituting sat-nav throughout the system. It may be in operation as early as 2008."

3 of 192 comments (clear)

  1. Re:Don't knw if anyone realizes this... by BasilBrush · · Score: 4, Interesting

    Yes, the Central Line underground line and the Docklands light railway in London are also computer driven. The Central Line has a driver sat in the cab doing nothing, but the DLR manages without. Mind you neither of them use sat nav to do it, what with them being undergrround much of the time.

  2. "1 metre accuracy" always amuses me.... by stimpleton · · Score: 4, Interesting

    ...as the onboard unit would have to send data at the rate of hundreds of location datagrams per minute. The point being, a location is a point in time - may not be relevant 30 seconds later, travelling at 150km/hr. Trains move quite quickly, and given past British rail mishaps, existing systems must have to be sped up a bit.

    With that said, GPS/GPRS units would have to communicate fairly frequently. At the very most a location sent to the server(probably over GPRS as a UDP datagram) every 2 minutes.

    In New Zealand, the GSM provider here (business plan) charges per 10,000KB packet, even for a 500byte datagram :-(

    Some rough maths:
    A location data packet(charged at 10k) every 1 minute.

    Thats 0.6 MB per hour.
    Train runs, say, 10 hours per day, thats 6mb.
    Per month thats 180mb.
    In New Zealand, thats about $200 of data.
    In my town, a taxi company uses it. The combined cost per month is $33,000 in data charges.
    And thats on 5 min updates!
    Anyone got some info on charges from other countries?
    IE how much will is cost our pommie friends per month per train, running 10 hr/days, sending location every 5,2,1 minutes, 30 seconds?

    --

    In post Patriot Act America, the library books scan you.
  3. Re:First impression by Bazman · · Score: 4, Interesting

    The fact that trains can't wander all over the place is part of the problem! If a faulty-set switch causes two trains to be heading for each other on the same piece of track, you can't tell them both to turn left, like you could do with airplanes.