Train Selects Blocked Path

Don't know how to use a machine? Looking for efficient setups? Stuck in a mission?
Post Reply
Bacon117
Burner Inserter
Burner Inserter
Posts: 11
Joined: Mon Apr 01, 2019 10:31 pm
Contact:

Train Selects Blocked Path

Post by Bacon117 »

I thought the trains were supposed to select unblocked path if one is blocked. I have a station on one path (red arrow in picture) and a main line on the other (green arrow). Some of my trains are selecting the blocked path (red arrow), but not always. Usually they select the green arrow path. I suppose I could recajigger the exit of that station to make that path undesirable, but I'm open for other suggestions.

In summary: Train should go down green arrow, but it goes down red arrow, which is blocked.

Thanks.
Attachments
Untitled.png
Untitled.png (3.46 MiB) Viewed 3981 times

DaleStan
Filter Inserter
Filter Inserter
Posts: 368
Joined: Mon Jul 09, 2018 2:40 am
Contact:

Re: Train Selects Blocked Path

Post by DaleStan »

Where is the train trying to go?

It certainly isn't trying to go to the disabled trainstop, but that doesn't help me figure out where it is going.

Bacon117
Burner Inserter
Burner Inserter
Posts: 11
Joined: Mon Apr 01, 2019 10:31 pm
Contact:

Re: Train Selects Blocked Path

Post by Bacon117 »

It's trying to go to a station to the east. I added a yellow arrow to the picture to show the desired path. I also took a screen shot showing the desired path from the map. I can't see any reason why it picks that path, instead of the desired yellow arrow path.
Untitled.png
Untitled.png (3.18 MiB) Viewed 3975 times
Train Path.png
Train Path.png (278.71 KiB) Viewed 3975 times

DerGraue
Fast Inserter
Fast Inserter
Posts: 151
Joined: Mon May 30, 2016 12:12 pm
Contact:

Re: Train Selects Blocked Path

Post by DerGraue »

Use chain signals to prevent the train from going into rail section where they are not allowed to stop.
If you look at your image you can see that your train has no other option at this point than going through the blocked path. Put a chain signal in front of the junction that the train has already entered and use chain signals up to the station to block this path if there is a train at the steel loading station.
Also note that your inserter train can not leave while there is a steel loading train, you might want to fix that.

Bacon117
Burner Inserter
Burner Inserter
Posts: 11
Joined: Mon Apr 01, 2019 10:31 pm
Contact:

Re: Train Selects Blocked Path

Post by Bacon117 »

I'll try the chained signals. I don't ever use those, but I'll try it. The picker train can leave. I think I took out a signal trying to figure out what is going on when I took the screen shot.

Bacon117
Burner Inserter
Burner Inserter
Posts: 11
Joined: Mon Apr 01, 2019 10:31 pm
Contact:

Re: Train Selects Blocked Path

Post by Bacon117 »

Tried a chain signal, but the train still chose the wrong path. I made a cheesy fix, see below, but it a lot my stuff here is cheesy, lol. Still would like to know why the train does this. If I pick other stations to the east, it still follows the same general path, but skips the blocked one, so I don't know...
Train path fix.png
Train path fix.png (3.94 MiB) Viewed 3973 times

DaleStan
Filter Inserter
Filter Inserter
Posts: 368
Joined: Mon Jul 09, 2018 2:40 am
Contact:

Re: Train Selects Blocked Path

Post by DaleStan »

I don't see anything obvious, then. Please post a save from before the train leaves the previous station.

quyxkh
Smart Inserter
Smart Inserter
Posts: 1027
Joined: Sun May 08, 2016 9:01 am
Contact:

Re: Train Selects Blocked Path

Post by quyxkh »

It's on that path, so at some point it must have looked like the shortest path — and in particular, when its braking point hit the red signal it's stopped at now, it still looked like the shortest path.

I notice there's a stop on the other path too. Pretty sure when this train arrived there was a train at both stops. I don't see a lot of steel on those belts, how long has that train been there?

User avatar
BlueTemplar
Smart Inserter
Smart Inserter
Posts: 2420
Joined: Fri Jun 08, 2018 2:16 pm
Contact:

Re: Train Selects Blocked Path

Post by BlueTemplar »

It takes some experience to get chain signals right - the chain signal tutorial is a good way to start.
BobDiggity (mod-scenario-pack)

Loewchen
Global Moderator
Global Moderator
Posts: 8272
Joined: Wed Jan 07, 2015 5:53 pm
Contact:

Re: Train Selects Blocked Path

Post by Loewchen »

Because the southern route contains two unscheduled train stops while the northern one contains only one. Place train stops on a parallel track instead of putting them directly on track you expect other trains to pass through.

User avatar
BlueTemplar
Smart Inserter
Smart Inserter
Posts: 2420
Joined: Fri Jun 08, 2018 2:16 pm
Contact:

Re: Train Selects Blocked Path

Post by BlueTemplar »

Yeah, the extra steps that trains take to avoid train stops can be a bit of a trap, especially when starting out with train network !
BobDiggity (mod-scenario-pack)

astroshak
Filter Inserter
Filter Inserter
Posts: 597
Joined: Thu May 10, 2018 9:59 am
Contact:

Re: Train Selects Blocked Path

Post by astroshak »

There ARE circumstances where you will want to put multiple train stations on the same line, but generally speaking, you only want one train station per line, and you do not want train stations on through-ways.

This is so that regardless of whether or not a train needs to sit there (go to this station and remain until FULL, go to that station and remain until EMPTY) other trains need to get by. Having stations in the through-ways creates the situation where the train that you need to get to this station so that train can move, is blocked by that train waiting for something.

And TC, learn chain signals. They are what allow you to easily make branching paths for trains to go through, while allowing for the blockages of one or more of those paths. A train parking lot (also known as a stacker) is an excellent example of this branching paths concept - all trains looking to go to a given station must pass through the stacker, but with chain signals, multiple trains stack up in parallel (one per line in the stacker) and leave to go onto the station one at a time once the way ahead is clear (usually, one or more station has opened up).

You may find though, that you need more space for your rail system ...

Post Reply

Return to “Gameplay Help”