Re: ATP

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

bub123@hotmail.com wrote:

>Darryl Georgee wrote:
>> 
>> "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 :-)
>> .

>The one thing that is missing from this discussion is the fact that both
>the ATC and ATP are supervisory systems.(They are there to monitor what
>the Driver is doing. If they detect a parameter outside the programmed
>limits they act to control the train, ie they applies the brakes to
>bring the train to a stop.

>As Daryl and others know this part of the system works very well....
>Problem is the Driver is sometimes in full control  of the train (I know
>Daryl sometimes may not be the best word to use.)

>The other benefit of ATP ( in theory) is that it knows part of the next
>three routes in front of the train (speeds, signals etc).

>The biggest problem is that the system needs to refresh where the loco
>is on the train in relation to signals to be safe. When it gets lost all
>the system can do is apply brakes to take control.

>Also the remarks about ATC being intermittent system is correct, but a
>good controller can stop that event happening by planning his moves with
>the knowledge that the system will not update until it goes passed the
>next beacons.  At some long crossing loops they have beacons mid yard
>that do update the aspect of the next signal.

>That is my two cents worth.. good thread keep the discussion going.

	Back again,yes ATP  does supervise but IMHO it will be VERY
interesting to be in court the first time the computer print outs from
the idiot box are tendered as evidence.
I MAY be wrong BUT and Briister worth hi/her $4000.00 a day or wotever
will challenge QR and Westec to prove that the info on the print out
is correct and/or accurate. This assumes there is no unbiased 3rd
party who can do so :-)