4-way intersections: Throughput and deadlocks [image heavy]

Smart setups of railway stations, intelligent routing, solutions to complex train-routing problems.
Please provide - only if it makes sense of course - a blueprint of your creation.
Locked
User avatar
hansjoachim
Fast Inserter
Fast Inserter
Posts: 239
Joined: Wed Apr 26, 2017 7:03 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by hansjoachim »

Tallinu wrote:
Fri Dec 07, 2018 11:03 am
If a forced signal causes any trains to crash, that probably constitutes a bug.
Yeah, It probably is. I put in a mechanism to prevent it in my merger.

immortal_sniper1
Filter Inserter
Filter Inserter
Posts: 771
Joined: Sun Jun 03, 2018 8:54 am
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by immortal_sniper1 »

hansjoachim wrote:
Fri Dec 07, 2018 4:51 pm
Tallinu wrote:
Fri Dec 07, 2018 11:03 am
If a forced signal causes any trains to crash, that probably constitutes a bug.
Yeah, It probably is. I put in a mechanism to prevent it in my merger.
i forgot to ask were there any signal problems in the design i posted here 2-3 days ago?

User avatar
hansjoachim
Fast Inserter
Fast Inserter
Posts: 239
Joined: Wed Apr 26, 2017 7:03 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by hansjoachim »

immortal_sniper1 wrote:
Sat Dec 08, 2018 8:56 pm
hansjoachim wrote:
Fri Dec 07, 2018 4:51 pm
Tallinu wrote:
Fri Dec 07, 2018 11:03 am
If a forced signal causes any trains to crash, that probably constitutes a bug.
Yeah, It probably is. I put in a mechanism to prevent it in my merger.
i forgot to ask were there any signal problems in the design i posted here 2-3 days ago?
It doesnt support turning left from the outer lane, and the throughput is very low. Why did you choose this design?
The signals looks correct

immortal_sniper1
Filter Inserter
Filter Inserter
Posts: 771
Joined: Sun Jun 03, 2018 8:54 am
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by immortal_sniper1 »

hansjoachim wrote:
Sat Dec 08, 2018 9:25 pm
immortal_sniper1 wrote:
Sat Dec 08, 2018 8:56 pm
hansjoachim wrote:
Fri Dec 07, 2018 4:51 pm
Tallinu wrote:
Fri Dec 07, 2018 11:03 am
If a forced signal causes any trains to crash, that probably constitutes a bug.
Yeah, It probably is. I put in a mechanism to prevent it in my merger.
i forgot to ask were there any signal problems in the design i posted here 2-3 days ago?
It doesnt support turning left from the outer lane, and the throughput is very low. Why did you choose this design?
The signals looks correct
it was a RHD conversion of a good LHD design
as i said i wasnt sure about the signals tehere is probably one that is on the wrong side deadlocking everything it did 71 so surely there is a signal problem ill look into it
viewtopic.php?f=194&t=46855&start=480

User avatar
hansjoachim
Fast Inserter
Fast Inserter
Posts: 239
Joined: Wed Apr 26, 2017 7:03 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by hansjoachim »

immortal_sniper1 wrote:
Sat Dec 08, 2018 10:34 pm

it was a RHD conversion of a good LHD design
as i said i wasnt sure about the signals tehere is probably one that is on the wrong side deadlocking everything it did 71 so surely there is a signal problem ill look into it
viewtopic.php?f=194&t=46855&start=480
How are you going to address the lack of left turns for the outer lane? Heavy use of lane switchers?
You could easily get much higher throughput with 2 lanes if the alternativ is using this design.

I think the singal problem might be because of the right turns from the inner lane. There should be more chain signals there.

immortal_sniper1
Filter Inserter
Filter Inserter
Posts: 771
Joined: Sun Jun 03, 2018 8:54 am
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by immortal_sniper1 »

hansjoachim wrote:
Sat Dec 08, 2018 10:46 pm
immortal_sniper1 wrote:
Sat Dec 08, 2018 10:34 pm

it was a RHD conversion of a good LHD design
as i said i wasnt sure about the signals tehere is probably one that is on the wrong side deadlocking everything it did 71 so surely there is a signal problem ill look into it
viewtopic.php?f=194&t=46855&start=480
How are you going to address the lack of left turns for the outer lane? Heavy use of lane switchers?
You could easily get much higher throughput with 2 lanes if the alternative is using this design.

I think the singal problem might be because of the right turns from the inner lane. There should be more chain signals there.
i reexamined the design concept from this forum and the inner lane cant go right and the outer one cant go left
ill fix it with some lane switches and a setup that "arranges the trains before the junction "

mobieh22
Manual Inserter
Manual Inserter
Posts: 2
Joined: Mon Apr 09, 2018 1:45 am
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by mobieh22 »

https://pastebin.com/178Qe8VZ this is an intersection I built, its meant for 3 car trains
Attachments
20190117114157_1.jpg
20190117114157_1.jpg (989.19 KiB) Viewed 6724 times

User avatar
hansjoachim
Fast Inserter
Fast Inserter
Posts: 239
Joined: Wed Apr 26, 2017 7:03 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by hansjoachim »

mobieh22 wrote:
Thu Jan 17, 2019 7:47 pm
https://pastebin.com/178Qe8VZ this is an intersection I built, its meant for 3 car trains
Really cool looking intersection, I like the amount of solarpanel/accumulators you have put in it.

For throughput, left turns are big problem. As if you have to take left turn you have to take a full round and block all other paths.

Jap2.0
Smart Inserter
Smart Inserter
Posts: 2339
Joined: Tue Jun 20, 2017 12:02 am
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by Jap2.0 »

hansjoachim wrote:
Fri Jan 18, 2019 8:07 am
mobieh22 wrote:
Thu Jan 17, 2019 7:47 pm
https://pastebin.com/178Qe8VZ this is an intersection I built, its meant for 3 car trains
Really cool looking intersection, I like the amount of solarpanel/accumulators you have put in it.

For throughput, left turns are big problem. As if you have to take left turn you have to take a full round and block all other paths.
No, it isn't great, but it's not especially below average for left turns. Of course, I'm not sure if this is necessarily the shortest case (and if it isn't, then it will have fairly bad throughput.
Attachments
Pic01.png
Pic01.png (1.12 MiB) Viewed 6690 times
There are 10 types of people: those who get this joke and those who don't.

User avatar
hansjoachim
Fast Inserter
Fast Inserter
Posts: 239
Joined: Wed Apr 26, 2017 7:03 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by hansjoachim »

mobieh22 wrote:
Thu Jan 17, 2019 7:47 pm
https://pastebin.com/178Qe8VZ this is an intersection I built, its meant for 3 car trains
It also deadlocks very easily. I had it running for 30 sec before it completely deadlocked. You have to add some chain signals to prevent that from happening.
Attachments
3 car Intersection.jpg
3 car Intersection.jpg (6.47 MiB) Viewed 6676 times

mrvn
Smart Inserter
Smart Inserter
Posts: 5681
Joined: Mon Sep 05, 2016 9:10 am
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by mrvn »

hansjoachim wrote:
Sat Jan 19, 2019 7:39 am
mobieh22 wrote:
Thu Jan 17, 2019 7:47 pm
https://pastebin.com/178Qe8VZ this is an intersection I built, its meant for 3 car trains
It also deadlocks very easily. I had it running for 30 sec before it completely deadlocked. You have to add some chain signals to prevent that from happening.
There also seem to be a few connections that can never be taken by a train. I mean the connection of the two loops. The two tracks go in opposite directions with neither train able to enter the connection. Why aren't the signals blinking there?

nafira
Fast Inserter
Fast Inserter
Posts: 107
Joined: Fri Mar 16, 2018 12:20 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by nafira »

Hi fellows :)

This is my setup that I made without checking in here before. I find pretty good, but there's some problems.
My trains drive on the right side, not left.

Pro :
+ No deadlock, impossible
+ Simultaneous 2*2 way train on long lanes is possible
+ Very compact
+ Modular
+ Use rounds to place factories or storage
+ Made for 2 wagons trains (perfect on that)
+ Extensible to 3 wagons

Cons :
- No loop
- Slows down trains a bit in very stretched areas
- Quite annoying if you have to shift the lanes

Here it is :

2*2 lanes *4 ways :
Image


2*2 lanes *3 ways :
Image


Turn :
Image


Buffer of train before entering or for stations : (juste repeat)
Image


Just a small precision : when you enter a crossing, you need to enter with chained signal. If you put the previous BP just before making a crossing, you'll have normal signals, which is bad. Exiting a crossing isn't. So remember to either replace the signal (which bots can't do).
I've made a special BP for entering :



If you have long distance and don't want to slow down your trains, you can just remove switching between lanes, so they be affected if a train is nearby (because of the chained signal).
Another thing Inoticed during my "train"ing on this subject, is that making turnovers in a 4 way setup, will end up most of the time in traffic jam. It's safer I think to let them take 5 more seconds to go around other turns.

It's also not the most compact but it let you use tracks to put stations without shifting right in the middle of nowhere.

Hope it will help or give a better idea to someone !

AlexAegis
Inserter
Inserter
Posts: 41
Joined: Sat Jun 04, 2016 10:25 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by AlexAegis »

Classic design 4 way 3 spacing 2 lane 1 picture:

Blueprint: https://factorioprints.com/view/-LWx8p9ga_BOerpE6Q1b

Throughput can reach around 50/m (with 2-4 trains) but my test map is different so it might not be precise. It's also deadlock free.
(I know it's very basic but haven't seen a 3 spacing, right hand drive version here)
4way classic.png
4way classic.png (8.18 MiB) Viewed 6576 times

GrumpyJoe
Filter Inserter
Filter Inserter
Posts: 443
Joined: Fri Apr 06, 2018 7:10 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by GrumpyJoe »

mrvn wrote:
Mon Jan 21, 2019 2:13 pm
hansjoachim wrote:
Sat Jan 19, 2019 7:39 am
mobieh22 wrote:
Thu Jan 17, 2019 7:47 pm
https://pastebin.com/178Qe8VZ this is an intersection I built, its meant for 3 car trains
It also deadlocks very easily. I had it running for 30 sec before it completely deadlocked. You have to add some chain signals to prevent that from happening.
There also seem to be a few connections that can never be taken by a train. I mean the connection of the two loops. The two tracks go in opposite directions with neither train able to enter the connection. Why aren't the signals blinking there?
signals are only blinking when a block isn´t entirely "enclosed" by signals on all ends, they dont tell what you found.
interesting thing to dig into tonight, i like the looks of it

User avatar
hansjoachim
Fast Inserter
Fast Inserter
Posts: 239
Joined: Wed Apr 26, 2017 7:03 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by hansjoachim »

AlexAegis wrote:
Thu Jan 24, 2019 12:02 am
Classic design 4 way 3 spacing 2 lane 1 picture:

Blueprint: https://factorioprints.com/view/-LWx8p9ga_BOerpE6Q1b

Throughput can reach around 50/m (with 2-4 trains) but my test map is different so it might not be precise. It's also deadlock free.
(I know it's very basic but haven't seen a 3 spacing, right hand drive version here)
In Set 1 it got 30 trains/min
It is also not correctly signaled. If one lane is blocked the entire intersection is blocked, as it lacks chain signals. It won't hard deadlock, though pretty close, it gets very congested.
If you fix the signals the throughput would increase

User avatar
hansjoachim
Fast Inserter
Fast Inserter
Posts: 239
Joined: Wed Apr 26, 2017 7:03 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by hansjoachim »

nafira wrote:
Mon Jan 21, 2019 7:30 pm
Hi fellows :)

This is my setup that I made without checking in here before. I find pretty good, but there's some problems.
My trains drive on the right side, not left.

Pro :
+ No deadlock, impossible
+ Simultaneous 2*2 way train on long lanes is possible
+ Very compact
+ Modular
+ Use rounds to place factories or storage
+ Made for 2 wagons trains (perfect on that)
+ Extensible to 3 wagons

Cons :
- No loop
- Slows down trains a bit in very stretched areas
- Quite annoying if you have to shift the lanes


Hope it will help or give a better idea to someone !
The intersections are lacking a lot of signals. Trains that doesn't intersect has to wait for each other.

The switcher prevents two trains to go the same direction at the same time, you need signals to seperate them.
The red block shouldn't include both lanes.
Attachments
Laneswitcher.png
Laneswitcher.png (12.25 KiB) Viewed 6543 times

mrvn
Smart Inserter
Smart Inserter
Posts: 5681
Joined: Mon Sep 05, 2016 9:10 am
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by mrvn »

nafira wrote:
Mon Jan 21, 2019 7:30 pm
Hi fellows :)

This is my setup that I made without checking in here before. I find pretty good, but there's some problems.
My trains drive on the right side, not left.

Pro :
+ No deadlock, impossible
+ Simultaneous 2*2 way train on long lanes is possible
+ Very compact
+ Modular
+ Use rounds to place factories or storage
+ Made for 2 wagons trains (perfect on that)
+ Extensible to 3 wagons

Cons :
- No loop
- Slows down trains a bit in very stretched areas
- Quite annoying if you have to shift the lanes
That's about the worst setup you can make other than deadlocking. There can only ever be one train on the crossing and all other have to wait. Same for the lane changer. Which makes your 2 tracks identical to a single track. There can never be 2 trains in parallel. It just costs you nearly 3 times as much resources.

AlexAegis
Inserter
Inserter
Posts: 41
Joined: Sat Jun 04, 2016 10:25 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by AlexAegis »

hansjoachim wrote:
Thu Jan 24, 2019 11:52 am
AlexAegis wrote:
Thu Jan 24, 2019 12:02 am
Classic design 4 way 3 spacing 2 lane 1 picture:

Blueprint: https://factorioprints.com/view/-LWx8p9ga_BOerpE6Q1b

Throughput can reach around 50/m (with 2-4 trains) but my test map is different so it might not be precise. It's also deadlock free.
(I know it's very basic but haven't seen a 3 spacing, right hand drive version here)
In Set 1 it got 30 trains/min
It is also not correctly signaled. If one lane is blocked the entire intersection is blocked, as it lacks chain signals. It won't hard deadlock, though pretty close, it gets very congested.
If you fix the signals the throughput would increase
Sadly I don't know how can I improve this further

nafira
Fast Inserter
Fast Inserter
Posts: 107
Joined: Fri Mar 16, 2018 12:20 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by nafira »

mrvn wrote:
Thu Jan 24, 2019 1:20 pm
nafira wrote:
Mon Jan 21, 2019 7:30 pm
Hi fellows :)

This is my setup that I made without checking in here before. I find pretty good, but there's some problems.
My trains drive on the right side, not left.

Pro :
+ No deadlock, impossible
+ Simultaneous 2*2 way train on long lanes is possible
+ Very compact
+ Modular
+ Use rounds to place factories or storage
+ Made for 2 wagons trains (perfect on that)
+ Extensible to 3 wagons

Cons :
- No loop
- Slows down trains a bit in very stretched areas
- Quite annoying if you have to shift the lanes
That's about the worst setup you can make other than deadlocking. There can only ever be one train on the crossing and all other have to wait. Same for the lane changer. Which makes your 2 tracks identical to a single track. There can never be 2 trains in parallel. It just costs you nearly 3 times as much resources.
They wait indeed (I told so), but they don't deadlock, you can't say that ==>meaning manual intervention
The only way to deadlock this system is to have a train on every single track between the whole train infrastructure. It's almost 500 trains we talk about on my small map.
And, no, as joachim said, there's a problem if two trains want to make a race at the same time, but either way, once the train passed the small switch (which is nearly 0.1 sec), the way for the other train is free and it can predict and change its way during the run.

@hansjoachim : yes, it's quite annoying, because they will slow down, before entering the switch, so you just need to remove one switcher at each, not very costly. I said it too, that in long distance you should remove switches and keep signals (for crash purpose :p)
If you have an idea, I'll take it !

The whole point of the design is that the train thinks it can get very far, even if he has to stop, and then, the track becomes available because trains don't stop behind one another, and he reach its destination. This is made to create a network across all map, not point to point liaisons.

User avatar
hansjoachim
Fast Inserter
Fast Inserter
Posts: 239
Joined: Wed Apr 26, 2017 7:03 pm
Contact:

Re: 4-way intersections: Throughput and deadlocks [image heavy]

Post by hansjoachim »

AlexAegis wrote:
Thu Jan 24, 2019 5:52 pm
Sadly I don't know how can I improve this further
So I improved it with correct signals.
I also made a better version with extra right turns.

Original: 30 trains/min set 1

Correct signaled: 41 trains/min set 1

With extra right turns: 48 trains/min set 1
btw: those test are with rocket fuel. With Nuclear fuel the numbers would be higher
Blueprint book with both of the new version
Attachments
Extra right turns.jpg
Extra right turns.jpg (194.52 KiB) Viewed 6498 times
Correct signals.jpg
Correct signals.jpg (179.26 KiB) Viewed 6498 times
Last edited by hansjoachim on Fri Jan 25, 2019 5:55 am, edited 1 time in total.

Locked

Return to “Railway Setups”