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Can an AI loco run round it's own train?

Posted: Thu Oct 06, 2011 10:44 am
by spikeyorks
I have a milk train coming off my branch line in to a loop. I want the AI loco to uncouple from it's tankers, pull forwards in to a headshunt and then round round it's train before reattaching itself to the other end. Then I want it to drive off back in the direction from which it has come but now on my main line. Is this possible?

At the moment I can uncouple OK, I can do 3/4's of the run round manouvre but then I get stuck when the loco tries to get across a trailing point (which will be the track section that the loco must use to subsequently reverse back on to the tankers).

I have read somewhere that perhaps the wagons should not be coupled to the loco when the scenario starts but I haven't tried this yet.

Any comments would be helpful.

Thanks

Re: Can an AI loco run round it's own train?

Posted: Thu Oct 06, 2011 3:33 pm
by Kromaatikse
The official word is that coupling only works if the wagons involved have not moved since the start of the scenario. Thus a full run-round as you describe is not possible. If you try it, you should get a warning from the editor that the wagons "are not in the expected place".

This does seem like a rather arbitrary limitation, so I'm hopeful that when more pressing problems have been sorted out, the coupling operations can be made more flexible. I believe the current limitation is in place simply to ensure that the wagons are there when the AI gets to them.

You can, however, do a limited subset of the run-round, at least in theory. Either start with the loco already detached from the wagons, or finish with the loco next to but not coupled to the wagons. In most cases you can arrange for the player to move on before the limitation becomes noticeable.

Re: Can an AI loco run round it's own train?

Posted: Thu Oct 06, 2011 4:20 pm
by spikeyorks
The official word is that coupling only works if the wagons involved have not moved since the start of the scenario. Thus a full run-round as you describe is not possible. If you try it, you should get a warning from the editor that the wagons "are not in the expected place".
No warnings at all from Scenario Editor. In fact it appears that it will work as timings are given for the whole sequence of the operation (whether I use "marshal" or "couple" commands). Mind you the logic about the wagons being in their starting place makes total sense and, in fact, that type of coupling set up occurs in the same scenario.
You can, however, do a limited subset of the run-round, at least in theory. Either start with the loco already detached from the wagons, or finish with the loco next to but not coupled to the wagons. In most cases you can arrange for the player to move on before the limitation becomes noticeable.
Used to do this all the time in MSTS :) Some things don't change.

Thank you very much for your help.

Regards

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 1:26 pm
by transadelaide
Kromaatikse wrote:This does seem like a rather arbitrary limitation, so I'm hopeful that when more pressing problems have been sorted out, the coupling operations can be made more flexible. I believe the current limitation is in place simply to ensure that the wagons are there when the AI gets to them.
I don't think it's an arbitrary limitation at all. I think it's because the current version of the dispatcher is not capable of working out how to make drivers chase around a route finding vehicles yet.

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 1:44 pm
by AndiS
I also believe that the dispatcher has one initial plan. Now, that includes the initial position of rolling stock, as stored in the scenario file. As soon as you start the scenario, the physics engine starts moving around vehicles and the dispatcher is not updated about this. Thus the AI crashes into anything that was not there initially (and is not listed as something to couple to).

I think that most of the new AI coupling feature is a side effect of having scenario-specific stopping points. AI did couple before, when you managed to stop it right at the wagon. However, I guess that only from RW3 on, the dispatcher ticks of the couple-to instruction on the AI train's agenda.

This case simply shows how the perspective of someone simulating railway operations and the perspective of someone who is ordered to move around art assets in a plausible way with minimal programming effort can differ very badly.

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 2:59 pm
by 220389
Present moment AI Coupling is rather fussy.

It seems to be able to connect to an Player coaches etc if detached (50% of the time), If nothing has towed the load it will couple fine, if towed by it's self or another AI it rather stops massivly infront or just shunts into them and causes an AI Collison.

Hopefully that will be fixed as would open up a lot of activities instead of working around that current limitation.

Chris

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 5:46 pm
by spikeyorks
It's nice to see some more comments on this. Thanks.

I'm still not getting very far. I have given up having the AI driving in to the loop and have, instead, done as suggested and have the loco and wagons starting uncoupled in the loop. The end result is more or less the same as in my original post. The scenario timings calculate correctly, the loco pulls forwards in to the headshunt and then reverse back past the wagons until about 3/4s of the way along it slows right down to the 1 mph crawl.

I'm now wondering about two things. Firstly, where the loco stops is actually part of the main line so the loco is required to cross over a trailing point and then set back on to the wagons after that. Might that be a a problem? Secondly there are other AI services on the main line too. Could they somehow be stopping the run round operation from taking place?

As before any thoughts would be appreciated.

Regards

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 6:29 pm
by Kromaatikse
When you test the scenario, are you starting it straight from the editor or going back to the main menu first?

Starting from the editor can very easily cause crawling-AI problems, it seems.

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 6:55 pm
by CL5858
Yes always exit back to the main menu before testing your scenario.

Over the past few weeks I've tried a multitude of coupling tests with the AI and can conclude that the AI will couple to coaches or wagons that have been dropped off by an AI or player train as long as you have a stopping point at the end of the wagon or coach to be coupled to & then give the coupling loco a speed under 3 m.p.h, unlike railworks 2 the loco will hit the buffers & push the wagons or coaches back a little until it reaches the stopping point, where it will stop and couple.

What doesn't seem to work is run rounds the loco doesn't seem to be able to couple up again having de-coupled & run round. As yet I've not tested if it would couple to another rake having dropped one off.

The situation is far from adequate but is usable for now I think.

Regards

James

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 7:02 pm
by spikeyorks
I'm running from a game exit and restart. Also othe loco starts off at the proper speed, gets most of the way through the run round and only then drops to a crawl.

In the same scenario (on the other side of the tracks so to speak) I have a Jinty dropping off 4 wagons in the good shed and then picking up a brake van from an adjacent siding. This works fine so I must be doing something right there.

At the moment it's a bit puzzling and a bit frustrating.

Regards

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 7:33 pm
by Kromaatikse
It seems that you're running into a bug, then.

I'd say to report it to RSC, but since you're running on our own little route it'll be a bt difficult for them to replicate it. They are already working on the bug from different examples, though.

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 8:56 pm
by Kariban
CL5858 wrote: Over the past few weeks I've tried a multitude of coupling tests with the AI and can conclude that the AI will couple to coaches or wagons that have been dropped off by an AI or player train as long as you have a stopping point at the end of the wagon or coach to be coupled to & then give the coupling loco a speed under 3 m.p.h, unlike railworks 2 the loco will hit the buffers & push the wagons or coaches back a little until it reaches the stopping point, where it will stop and couple.
This will not work, annoyingly;

* AI drops off coach - fine if it's the last command before moving off.
* Player picks up coach
* Player leaves coach elsewhere
* Later, player picks up coach again
* Player shunts the coach onto the back of a different stationary AI consist and uncouples
* Stationary AI tries to couple, couplings visibly join, immediately gets AI collision.

Tried alternate version of the last two instructions

* Player shunts the coach onto the back of a different stationary AI consist and couples it.
* Player uncouples
* Stationary AI is now a zombie, does have it's own driver still but won't do anything.

Re: Can an AI loco run round it's own train?

Posted: Fri Oct 07, 2011 9:56 pm
by spikeyorks
The first screenshot shows the starting position of the AI loco and consist (uncoupled). You can just glimpse the trailing crossover in front of the DMU.



Whilst the second shows the AI loco pulling in to the headshunt prior to using the crossover in front of it to access the main line.



Apologies about the weather :)

Re: Can an AI loco run round it's own train?

Posted: Sat Oct 08, 2011 2:56 pm
by spikeyorks
Very anoyed now after wasting most of the day on this and still getting nowhere with it :roll:

I can get the loco now from the starting position (screenshot 1) to run round and join back up to the rear of the consist. However once coupled (and the wagons move and everything looks OK) the loco promptly drives off leaving the wagons behind. I have stop commands before and after coupling, I have tried couple to front/couple to back and even marshalling but always end up with the same result. (Apart from the time when I put couple to front and couple to back in the same set of instructions.....in that case it caused AI on the main lines a mile away to stop rather than affect the actual milk train).

Should I be using either the "Consist" or "Instruction" tick boxes?

As always any comment will be appreciated.

Thanks

Re: Can an AI loco run round it's own train?

Posted: Sat Oct 08, 2011 7:22 pm
by TractorBasher
Do you have the Rail Simulator box ticked in the content providers list?