Re: ATP

[phaedrus@ultra.net.au (Darryl Georgee)]

"MattyQ" <matticue@corplink.com.au> wrote:


>mcfergus@my-dejanews.com wrote in message
><7cs732$mf6$1@nnrp1.dejanews.com>...
>>For the benefit of the rest of us, could someone please elaborate on the
>above
>>conversation? I for one would probably find it interesting if I knew what
>you
>>were talking about!


>I will explain what I know of ATP. This is how it is supposed to work as I
>understand it but they seem to be having much problems with it at the
>moment.

>ATP is the Westinghouse continuous Automatic Train Protection system being
>introduced to QR's diesel locomotive, tilt train and soon, IMU fleet. It
>performs a similar task to the Ericsson Automatic Train Control system
>fitted to 3900 class electric locomotives and ICE units.

>Both ATC and ATP are cab based computer systems designed to receive
>information about the track geography, signal aspects and temporary
>worksites etc. and keep the speed of the train in check accordingly. The two
>systems differ in many ways. ATC is manufactured by Ericsson and is regarded
>as "intermittent". Information can only be fed to the locomotive by means of
>track mounted beacon groups. The drivers ATC displays show what speed you
>should be doing now and if required to slow down, what speed you must slow
>down to.

>ATC has proven to be much more reliable than ATP even though it is a more
>primitive system. The only source of information to a loco is via beacon
>groups. If a loco crosses a beacon group associated with a signal at stop,
>the system will force the driver to stop the train at the signal. If,
>however, the signal clears after the loco has crossed the beacon group, the
>computer will keep the loco under restriction until it crosses the next
>beacon group and the restriction is lifted hence the term "intermittent".

>The idea behind ATP is that it is a "continuous" system. Track mounted
>transponders are placed at strategic locations on the track but only really
>hold information on track geography such as curves and stations. In other
>words, information which never changes. ATP has a second source of
>information which is transmitted to the loco by means of radio waves. This
>information is usually parameters which can change and affect the trains'
>performance, such as signal aspects. If a signal is at stop, the ATP system
>will force the driver to stop the train as does the ATC system. The
>difference is, if the signal clears, the on board computer is updated
>straight away and the restriction is immediately lifted.

>As I said earlier, this is my interpretation of how ATP is SUPPOSED to work.
>If I have made any errors, Daryl Georgee may wish to comment.

>Regards

>Matt Smith
>Brisbane, Queensland
>Reply to matticue@hotmail.com

>You can't slam a revolving door.

 Right on Matt, but as with many things the theory is good
 but in practice it has been/is a nightmare for the people on
 the ground who have been inflicted with it. As prev mentioned.
 Westec are up to ver 16 on the software. It still has a long way
 to go. The difference between driving a train with and without ATP
is like chalk and cheese. 
But then I'm only a driver so wot would I know :-)