Hydrate schedule timing point locations

[Trainjunkies]

Hi Folks,

Does anybody have any experience hydrating/decorating "missing" timing point locations from a schedule document or any advise on where to start? By missing I believe it's not a mandatory timing location for schedule and thus not present.

As an example the 0805 Avanti Pendo' from Piccadilly [MNCRPIC] to Euston via Macclesfield [MACLSFD] will pass Bramhall [BMHL] but the timing point location is not in the CIF extract.

I'm assuming it could be possible with BPLAN timing link records but am unsure of what rules need to be adhered to safely hydrate.

Cheers, Ben

[Matthew Burdett]

The way I've done something like this is :

I have compiled a simple database with a "to" point and a "from" point ,

The two point lists all of the tiplocs accessible from the FROM point

A mileage and chainage captured from the sectional appendix is in said sheet between those two points.

Using an algorithm you can give your program the from point and to point, and with some parameters of some sort, to work out the points involved - like a shortest route algorithm or something.

Then return the points in that route (the non mandatory points)

For the timings my use case probably needs some refining, but in its simplest form;

Using the mileage and chainage, and use the departure time and arrival time between the two primary tiplocs timetabled. Use the distance speed triangle or whatever, to work out a speed the train is using between the two mandatory tiplocs, and factor in the mileage to the non mandatory tiplocs with the speed, to deduce a time it will pass.

Now obviously you've got things like line speed etc to take into account, so it's not perfect. Some tiplocs are further than others in between but in my usage, I've used the time it takes between the two mandatory points, to work out a speed using the mileage too, and used that to work out a time with the mandatory to non mandatory points.

Others can comment but that's the way I use for my own personal useage.

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[Peter Hicks]

Hi Ben

I don’t think you should call it ‘hydrating’ or ‘decorating’ - they’re very subjective words which cover up the fact you’re inventing new sectional running times at many locations.

Ignoring my feelings on the matter, the situation with BPLAN timing links is tricky. Each timing link is for a particular class of rolling stock, and a Class 390 won’t have timing links for Bramhall in BPLAN, as it’s not a mandatory timing point because no Class 390s stop there. If you wanted to infer or suggest it, you’d have to pick a traction type that’s close in speed and other characteristics to a 390 - such as a Class 175, 195 or 331, and then you’d need to find a pass-to-pass timing link since your 0805 MAN-EUS doesn’t stop there.

Another way to do it is not to use BPLAN and instead use a geospatial model - something Network Rail haven’t released yet (but I live in hope!). With the right level of detail and timing points correctly overlaid, you could work out the timed speed of the train between a pair of timing points, and then work out what the speed of the train might be at intermediate locations. Since trains are only timed at a 30-second granularity, you might run in to problems trying to report or measure the performance of trains at these locations.

Out of interest, what’s your use case here? Is it for an operational system?


Peter


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[Trainjunkies]

Hi Both,

Thanks for the replies and context regarding the data sets and solutions.

It would be used for an operational system, where I can see as many movements as possible at a TIPLOC regardless of traction Class or CIF train category. With the example being Avanti 390/XC 22* at Bramhall when there are no CIF location records for those services even though they pass through the TIPLOC - Freight/Charter would be a nice to have as well.

Jumping through the BPLAN timing links from both comments initially appears quite involved for the accuracy and value of the feature - Academically I'm interested but I don't think it's practical right now.

Would you know of any other data sets available? Open or commercial.

Cheers, Ben