Platform allocation

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as1
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Platform allocation

Post by as1 »

All,

I am having problems with trains repeatedly queuing for a specific occupied platform when there are other platforms available. I've highlighted the platform, with the blue box, on the attached. Can anyone advise what might be causing this? I've checked that there is a route to the spare platforms. The only thing I can think of is that the size of the station is causing the issue?

I haven't seen it happen with any of the other entrance lines.

Thanks
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JGR
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Re: Platform allocation

Post by JGR »

You should remove all the platform entrance signals. They're not required and are the cause of this queuing behaviour.
With no signal in front of each platform entrance PBS should reserve a route to an unoccupied platform.
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Auge
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Re: Platform allocation

Post by Auge »

Hello
JGR wrote: 03 Dec 2019 13:40 You should remove all the platform entrance signals. They're not required and are the cause of this queuing behaviour.
With no signal in front of each platform entrance PBS should reserve a route to an unoccupied platform.
Yes, but whzen one uses restricted signal to guide trains to specific platforms, one needs these signals. In that case the two-way-path-signals should head to the platform (reverse them) to be passable from the backside.

Tschö, Auge
as1
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Re: Platform allocation

Post by as1 »

All,

Thank you for your help.

I forgot to mention that I have signals on the entrance to the platforms to stop trains reversing out of them. I also forgot to mention that I know the trains will queue if all the platforms are occupied, what I don't understand is why the trains are queuing when there are available platforms?

Thanks
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Re: Platform allocation

Post by _dp_ »

Trains only choose platforms when entering the station. But since you cut off station with signals they treat it as an ordinary junction going for the closest way out.
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JGR
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Re: Platform allocation

Post by JGR »

Auge wrote: 03 Dec 2019 14:38 Hello
JGR wrote: 03 Dec 2019 13:40 You should remove all the platform entrance signals. They're not required and are the cause of this queuing behaviour.
With no signal in front of each platform entrance PBS should reserve a route to an unoccupied platform.
Yes, but whzen one uses restricted signal to guide trains to specific platforms, one needs these signals. In that case the two-way-path-signals should head to the platform (reverse them) to be passable from the backside.

Tschö, Auge
In that case the platform entrance signals should be changed to one-way PBS, and the reserve through action added to each signal.
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as1
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Re: Platform allocation

Post by as1 »

All,

Thanks for your help.
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odisseus
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Re: Platform allocation

Post by odisseus »

This way to place signals could work, but you would have to use pre-signals instead of path signals.

Each ordinary signal in front of a platform entrance should be replaced by a one-way exit signal, and each one-way path signal in front of a station entrance should be replaced with an entry signal. Incoming trains will wait at the station entrance and the choice of a platform will be deferred until the moment when at least one platform is free.

That said, the layout of your station has multiple problems, and wrong signal type is just one of them. I believe some combination of a drive-through station, a separated junction and a sideline depot would serve your needs much better.
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Re: Platform allocation

Post by as1 »

Thanks for your advice. I've moved the depot that I have space to move.

With regards to the drive through station - everything stops at the station so I don't think drive through lines would be of use? Sorry if I misunderstood something in the link you provided.
Sorry I am not sure what you mean by a separated junction. Did you mean creating a design so that each incoming line only has access to some of the platforms to reduce the amount they cross each other?
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Re: Platform allocation

Post by odisseus »

I mean that the junction where two different routes merge into one should be made at some distance from the station. This way the station will have just one entrance, and there would be room to make that entrance more efficient and less cluttered.

However, if your routes comprise two different circuits that come together only at this station, then it is indeed the best to dedicate some of the platforms to each circuit, so that they don't actually share any piece of track. Remember, the most efficient junction is no junction at all.

If none of the trains drive through this station without stopping at it, then, of course, you don't have to build bypass tracks.
as1
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Re: Platform allocation

Post by as1 »

Thank you for your help.
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Re: Platform allocation

Post by AndreasBerlin »

Use pathsignals (bothway) on both sides of each platform, lights showing to the platform (and not oneway-pathsignals on one side and dualway-pathsignals on the other side). Trains will choose the next free platform if they enter the station and not an occupied platform.
On each track leading inwards the station place an oneway-pathsignal on the right side (if driving is on right side) just at the end of the track (close to the station).
On each track leading outwards the station place an pneway-pathsignal on the left side (if driving is on the right side) not at the beginning of the track but further on, as far away as the length of the longest train which goes to the station. This will avoid traffic jam, trains leave the station - and their platform - only if the last train leaving the station before has passed the outward signal. This keeps trains in stations instead of waiting on the track and incoming trains won't use a platform with a train "just leaving".

Is it correct that all four tracks in the upper left of the station (with blocksignals) leading out?

Have fun in building and signaling!
as1
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Re: Platform allocation

Post by as1 »

Sorry for my slow reply, I've been busy with some other things.

Thank you for your help.

Yes all of the tracks in the upper left lead out of the station. Two each to different destinations.

Sorry I don't understand the reason for putting path signals, facing the platform, on the side the trains enter the station? Is that to allow them to access the depot more directly?
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Re: Platform allocation

Post by AndreasBerlin »

Effects of placing dualway path signals at both ends of a platform (facing to the platform) are:
(a) trains can enter the platform from both ends and leave the platform in both directions
(b) this enables the next incomming train to use the nearest free platform
(c) this prevents incomming trains to choose a platform with a "leaving trains" (a trains half in and half out of the platform).
(d) this stops the blocking of incomming tracks by waiting trains.
Reaching a depot more directly might be a side effect.

The described signalling is not my idea, I found it in another forum and I tested it in many games.
I use it on normal and roll-in-roll-of stations.

Have fun
Andreas
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