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I'm sure this is probably the intended behavior (or is it?!) but I think chain signals are acting a bit...odd. If there are multiple trains waiting for a 'platform' at a station with more than one stop, they seem to decide on which platform they are going to before they reach the chain signals before the station. It's probably best illustrated with this picture:
As you can see, there's a vacant platform at the station (both stops have the same name) but the three trains waiting have already selected the upper platform and so aren't moving.

Is there any way to avoid this kind of situation whilst still avoiding any situation which might induce a deadlock?

replace the chain signals with regular signals, only use chain signals at a track intersection

Kewlhotrod wrote:replace the chain signals with regular signals, only use chain signals at a track intersection

I'm not really sure that would work. Making the centre section one block would just cause a train to block the entire intersection. If a train left from the other platform first then nothing would be able to move into that platform.

I played about a bit with the 'show train stop point' debug feature. It seems the trains do do some sort of analysing of free platforms / which train is likely to leave first. Putting a chain signal in the very middle bit and block signals at the exit to the waiting bays seemed to help a bit, but still occasionally something like this happenes:
This never actually happened for a very long period of time; this train did actually move into the free platform a few seconds after this. I'm guessing it has to do with the frequency that trains recalculate their route. Seems to happen about 5 seconds after a train has departed from a station.

they'll repath if they are stopped at a chain signal and there is another rout open

ratchetfreak wrote:they'll repath if they are stopped at a chain signal and there is another rout open

Assuming your theory is right and looking at the threadstarters screenshots:
Why don't the trains stopped at the chain signals repath into the other free station?

ratchetfreak wrote:they'll repath if they are stopped at a chain signal and there is another rout open

No, they don't. Well, maybe after a long time, but normally they just wait, as shown here.

Maybe it's a bug?! Several patches has been made to the repath algorithms. Maybe you can provide the save so other can look?

sfxdude wrote:I'm guessing it has to do with the frequency that trains recalculate their route. Seems to happen about 5 seconds after a train has departed from a station.

IIRC they *never* recalculate which exact station they are going to, it is decided when they leave the previous station. Even if a free station has the same name.

I cannot find the source now but I read an idea where you had a temporary station just before the real unloading stations, where all the ore trains would stop for 0 seconds. Then when they path the tiny distance to the real unloading stations they'll select the free one, assuming they are equally distant from the temp station.

Linosaurus wrote:IIRC they *never* recalculate which exact station they are going to, it is decided when they leave the previous station. Even if a free station has the same name.

This is what I thought. After reading this thread you were luring me into false hope that assigning two stations in the schedule would somehow select the empty one. Maybe it does, I've always just assumed they went to stations by order of the schedule.

Something .13 might fix if we get enough control using the circuit network.

I solved this behavior by adding a entry-station in front of my main station, where trains wait for 0 seconds.
The result is, that trains move to the entry station, stop there and look for a new route from there.

nobodx wrote:I solved this behavior by adding a entry-station in front of my main station, where trains wait for 0 seconds.
The result is, that trains move to the entry station, stop there and look for a new route from there.

Smart idea!

I wished we had waypoint-stations, so we can force trains to use a specific route (like in TTD)