Train Parking Lots no longer work? [SOLVED]

[zaanzabar]

In 1.1, you set up a parking lot, by setting up a dummy station, with a blocked signal before it at the parking lot. The station that is the actual destination could be disabled when full and the en-route trains would re-route to the parking lot. Station starts accepting trains again, and trains in the parking lot would re-path to the original station as soon as it was available.

Now, in 2.0, trains that path to the parking lot station, will not re-path. They are stuck no matter what I do, short of deleting the station entirely.

I have a full circuit network controlled train system from my 1.1 save that sends out requests for materials, and dispatches trains from a parking lot when called for. My own version of LTN type mechanics. This system now doesn't work.

Has anyone else encountered this? Anyone found a fix to this?

UPDATE - SOLVED: I have quite by accident discovered a way to make this work.

If you close a train signal by the circuit network, the train no longer sees it as a valid destination, and will repath.

Solution: Place a Chain signal before the dummy station, Controlled by circuit network. Place something on the tracks between that and the station so the chain signal is off. Use circuit network to lock the signal when the dummy station is no longer needed. Use this to force a train going somewhere, to repath.

Alternately: The circuit network is not necessary for this particular application. Simply having a station with the same name, with no limits, but has a train at it, will do the job. Set all the real stations to 1 train limit.

11-18-2024, 09-53-41.png (2.33 MiB) Viewed 47 times

[BlueTemplar]

Have you read the 2.0 train changes in the related FFFs ?
https://factorio.com/blog/search/train
(see the 2023 and 2024 ones)

[Tertius]

The major thing why your setup breaks is that disabled stations are not skipped any more in 2.0. Once a train was able to reserve a slot, it's driving there. If it wasn't able to reserve a slot, it's staying where it is with status destination full or path not found. Disabling a station just forces the station limit to 0, nothing more.

Train control has vastly changed. Old sophisticated methods of train control are usually obsolete and inferior to the new train interrupt mechanic in 2.0. Forget all what you did in 1.1. Throw away all your blueprints and train control mods and make a fresh start with interrupts. It's really cool.
To see how interrupts work, see https://factorio.com/blog/post/fff-389 and https://factorio.com/blog/post/fff-395

[zaanzabar]

The major thing why your setup breaks is that disabled stations are not skipped any more in 2.0.

Exactly. So far, I have been unable to figure out a way to make an interrupt work for a parking lot.

[zaanzabar]

Have you read the 2.0 train changes in the related FFFs ?

Yes.

This leads us onto another change in 2.0, disabling stops will no longer cause trains to skip the stations and repath.

This means the interrupts are ONLY checked when they leave a station. There is no longer a way to re-path while en-route. If the station is disabled by circuit before the train arrives, it will NOT divert. It will continue on until it passes through a station, where it then re-checks interrupts. This means that the train will have to actually GO to that disabled outpost ore station, before the interrupt to get fuel will trigger.

Whenever the train wants to leave the current station, it checks all the interrupts one by one, evaluating the interrupt conditions. If the conditions are fulfilled, the interrupt is activated and the targets are pasted into the current schedule as temporary stops.

By setting up the parking lot station to be "Parking Lot" and setting up an interrupt to divert there if destination is full, I can get the first half of the behavior working. However, due to the new changes, the train has to actually ARRIVE at the temporary station to clear it. This makes diagonal parking lots unusable, and they will now have to be much larger footprint to function. But to be fair, they DO work, technically.

It is far from "better" though. Unless I'm still missing something.

[Tertius]

A screenshot example for depots can be seen in fff-389, section "The depot problem".

[zaanzabar]

A screenshot example for depots can be seen in fff-389, section "The depot problem".

I saw that, but it does not address the 2 problems I have outlined. Essentially 1 problem I guess: trains will not re-path or check interrupts, except at a station.

I can not get these trains to move no matter what I try. (short of deleting that parking lot station)

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[Tertius]

If you copy the example from fff-389, your empty train will go to the depot instead of some loading station, if there is no free slot at any loading station. If it is en route to the depot this way, and some loading station opens up, the train will continue to drive to the depot. No way around this. Once at the depot, essentially doing nothing (simply don't use this 30 second waiting condition as in the screenshot), interrupts are checked again and the train will go to the new loading station.
If it bothers you that a train scheduled to the depot cannot be redirected on the fly, build the depot(s) near the unloading stations, so trains get there fast and the regular way out is through that depot anyway. My depot is directly behind all the unloading stations, not more than 50 tiles away.
You can have multiple depots distributed over your base, all with the same name, so trains will choose the nearest one.

Edit: forget this setup in your screenshot. You don't build depots this way.

An example of my newest design: the depot is on the top, each lane has a station. And a staging area in front of the unloading stations at the bottom for full trains, without a station, managed by chain signals and train limits in the unloading stations. The unloading stations have a static train limit of 2 and 3, so they need 1 or 2 lanes staging area, so the area is 17 lanes big, so there is enough space in case there are the maximum possible number of trains.

11-01-2024, 20-09-11.png (159.57 KiB) Viewed 760 times

[zaanzabar]

the train will continue to drive to the depot. No way around this.
...
My depot is directly behind all the unloading stations, not more than 50 tiles away.
You can have multiple depots distributed over your base, all with the same name, so trains will choose the nearest one.

My base has a stacker in front of each loading and unloading station. unfortunately they will no longer use them. If I have a depot station, (that they can actually reach) then the train will stay at the Depot until a slot opens up. Even if the depot is nearby, that is slower than the stacker AT the unloading station.

Also, I have all my stations named simply (item)DROP and (item)PICKUP, everywhere. So, if I have green circuits, it has a copper plate drop off. The behavior I am trying to do, is to have the train go to (Copper Plate)PICKUP, load up, go to parking lot, and wait until Any station in the network called (Copper Plate)DROP opens up. I can kind of do that, but I don't know where in the whole network that will open up next. What if the chosen depot is all the way on the other side of the base. I usually have the parking lot at the loading station, just to save as much time as I can.

What I had before was like this: especially at high throughput stations that have a large stacker in front, (with it's own dedicated parking lot station with train limit set to the size of the stacker.) If the drop stations are all full, the train will still path to the stacker, and wait there. Then with a circuit condition, it would disable the parking lot station, which would trigger a re-path check, and allow a train to leave the stacker and move to the drop off station. Once the slot is filled, the parking lot station would re-enable, and all other trains would then go back to pathing to the stacker.

[zaanzabar]

Back when I started this project, I had a setup like that (minus the depot). It worked fine, but the problem I was attempting to solve, was even distribution.

Let me explain:

Too Few trains:
In your screenshot, you have 3 iron ore stations. Lets say these stations unload into a buffer chest (can't tell if yours do). If all the stations are empty of a train, and one arrives, it goes to the first station. Eventually, the first station buffer chest will fill up, the train will go there, and wait for room to open up so it can unload. Meanwhile, station 2 and 3 are empty. What I wanted to try to do is have the train go to the station that has room for its delivery. To that end, I had a circuit network that reads the contents of that chest, and if it had room for a delivery, it enables the station. A train is then dispatched, and all is well.

Too many trains:
The rest of it was to increase throughput at high use stations by pre-loading trains, and stacking them nearby. Problems arose when I had more trains than stacker slots. Hence the parking lot. Parking lots were in the same area as the loading station, because I didn't know where the station that was going to open up was going to be.

It worked beautifully in 1.1 but now I can't make it work.

It is based on this video: (don't know if I can post links) Note the time stamp if you want to check it out.

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[Tertius]

Forget all those ancient guides and solutions. It seems you don't use train limits. They were implemented with 1.1 (so your guide made for 0.18 cannot include them) and manage how many trains will be allowed to drive to some station. If you use train limits properly, you don't have a need to activate or deactivate some station.
See https://factorio.com/blog/post/fff-361

Example for train limits: a static limit of 2 for any station results in up to 2 trains driving to that station. One train will arrive at the station and being loaded or unloaded. The other one will wait at the signal you put before the station. A limit of 3 will make 2 trains wait in front of the station, and to save space you can build a stacker and use chain signals to make them wait in parallel lanes in the stacker. It's also possible to have multiple stations and a unified stacker in front of all of them, with as many lanes as the sum of all train limits of the stations minus the numbers of stations (because each station has already space for one train).
So if you have 4 stations with train limit 2 each, the stacker needs to be 4 lanes wide to never overflow.

I found out static train limits of 2 are quite useful. This will make one train currently being loaded or unloaded, and one train currently driving to that station or waiting in front of it in a stacker, so it can proceed immediately to the station if the current train has finished loading or unloading.

In such a setup, you have as many trains as the sum of the slots of the loading stations plus the number of lanes in the depot for the empty trains. If you don't use a depot for empty trains, no additional trains.

[zaanzabar]

Thank you for your effort. You have been putting a lot of time and work into your responses.

I Have been using train limits. I was controlling them using the circuit network, based on buffer chest capacity. Each could have a capacity of 0-3 trains.

This whole thing developed over the course of about 100-200 hours. Adding features, tweaking combinators, fixing logic. It was balancing input from 8 drop off stations to my smelting plant, each input getting ore just as it needed it. Output was going to whatever station needed it, as they needed it. I used a minimum of trains for each resource, often only 1 or 2, to reduce congestion. On ore trains, because of the distances involved, I often had to seriously overpopulate the network to keep the rate of income steady. Trains that had no destination moved out of the way so other trains could use the station.

It was working beautifully in 1.1, but now is not possible. I guess I'm going back to the drawing board.

This whole thing could be fixed by returning to being able actually disable stations, not just set limits.
OR add interrupts that can kick in if the limit of the station they are heading to drops below the incoming train count.
OR using station priority, allow a stopped train to re-path to a higher priority station if one comes available.
OR allow interrupts to be canceled if it is no longer needed.
OR allow interrupts to be triggered while not at stations

Any one, by itself would allow me to continue my work. What I am looking for is if anyone has a solution to ANY of those situations.

[Tertius]

I'm reworking everything from scratch while playing a freshly created 2.0 map with Space Age. Gameplay is slightly different, and there are new tools available that make certain tasks easier or more straightforward. For example the possibility to connect many production machines to the circuit network and activate/deactivate them. And even change the recipe of assembling machines.

My new oil facilities for example don't need any pumps as valves any more to implement on-demand cracking of light/heavy oil. It's possible to directly control the corresponding chemical plants.
And quite some circuit contraptions can be simplified and reduced because of the separate red wire/green wire handling of input signals.

So it's worth to look into everything and use old blueprints just as example but build them completely new. Instead of worrying why some old stuff doesn't work any more, I'm approaching each task as if it is completely new.

Especially trains are something where you should destroy every single old blueprint. Track radius is different, track switches are possible with every spacing (not just to 4 tiles), station control is different (interrupts), congestion control is different (elevated rails), big power pole spacing is different (32 instead of 30, so if you made blueprints with big power pole spacing, you get 2 more tiles).

[SkerrittT]

I have spent most of the time since Factorio 2.0 was released creating new rail blueprints and getting a basic base established such that I can get the train system working. I said good goodbye to all my old blueprints and save games.

While hundreds of people will say the interrupt system is so wonderful and parameritization is a magnificent addition to the game the details seem a bit missing.

I have read all the FF ... notably ff 389 and 395 and have a few questions to which i find no answers such that :
Trains for Liquids and Trains for Items do not get mixed up ie: Liquid wagon trains try to pickup items or vise-versa;
So that multiple trains do not try to pickup at the same station at the same time;
So that multiple trains do not try to deliver to the same station at the same time;
that trains trying to deliver to a station do not get blocked by other trains that deliver there first (making the need for a delivery to disappear);
So that I can control the train traffic generated
So that i have adequate trains servicing stations
So that trains service all stations not just the closest station

I would like to do this without needing to becoming a software engineer and without mass combinators and wiring

I long for Factorio 1.1 (and prior).

[SkerrittT]

I have spent most of the time since Factorio 2.0 was released creating new rail blueprints and getting a basic base established such that I can get the train system working. I said good goodbye to all my old blueprints and save games.

While hundreds of people will say the interrupt system is so wonderful and parameritization is a magnificent addition to the game the details seem a bit missing.

I have read all the FF ... notably ff 389 and 395 and have a few questions to which i find no answers such that :
Trains for Liquids and Trains for Items do not get mixed up ie: Liquid wagon trains try to pickup items or vise-versa;
So that multiple trains do not try to pickup at the same station at the same time;
So that multiple trains do not try to deliver to the same station at the same time;
that trains trying to deliver to a station do not get blocked by other trains that deliver there first (making the need for a delivery to disappear);
So that I can control the train traffic generated
So that i have adequate trains servicing stations
So that trains service all stations not just the closest station

I would like to do this without needing to becoming a software engineer and without mass combinators and wiring

I long for Factorio 1.1 (and prior). Space Age looks terrific, but I doubt I will be playing it much longer.

[zaanzabar]

I have read all the FF ... notably ff 389 and 395 and have a few questions to which i find no answers such that :
Trains for Liquids and Trains for Items do not get mixed up ie: Liquid wagon trains try to pickup items or vise-versa;

not knowing your setup, use of the generic "Item" icon vs "fluid" icon may help here

So that multiple trains do not try to pickup at the same station at the same time;
So that multiple trains do not try to deliver to the same station at the same time;
that trains trying to deliver to a station do not get blocked by other trains that deliver there first (making the need for a delivery to disappear);
So that I can control the train traffic generated

use of train station limits may help here. Set limit to 1 or 2 (if you have space) will prevent too many trains from pathing to the station, limiting arrivals and traffic at the same time

So that i have adequate trains servicing stations

Not sure on this one. I'd just place multiple service stations around the map.

So that trains service all stations not just the closest station

This is my issue I'm trying to solve right now.

[SkerrittT]

Thanks but none of that solves the problems described.
Also what is a service station that you would just place around he map?

[zaanzabar]

I have all trains with an interrupt to go get fuel. I place fuel stops all around the map, so wherever they come from, they have one nearby.

I called them service stations because you did. (went back and looked) I thought you did....

I currently use a simple 1 arithmatic combinator per provider station. I run a wire to the storage buffer box(s). Divide that number by the quantity in 1 train load (stack size 50 = 4000) and use that number to set the train limit. Trains only path to these stations if the station has a full cargo load for it.

Requester stations need 2 combinators, only because I subtract result from above, from total capacity of the chest(s) (in train loads). This gives me how much room is available at the stop. Trains only path to these stations if the station has room.

would that help your setup?