An old shunting problem?

AntonyVW

Active member
I'm sure this is an old problem but cant for the life of me think what the cure is/was?
I'm setting up an AI which has to collect wagons form various sidings and assemble them ready for dispatch. At one point the loco has to reverse over a set of points into a siding then move forward to collect the wagons waiting ahead. The siding it initially reverses into is quite a long one and at the far end are a couple of wagons waiting to be collected later in the sequence.
The problem is that the loco refuses to reverse into the siding because of those wagons. Ive tried to add as many as 3 invisible signals between the junction and the wagons but the loco refuses to enter the siding. If I remove the wagons it completes the task without issue, so I know the problem lies with the wagons.

Can anyone shed any light on this issue please? It would be a pity to have to move the wagons to another location just because the loco wont complete its task.
 
Set the path to the siding and then use "SetDCCThrottleTo", trial and error required to find the setting speed as locos vary, and then use "CoupleAhead" command.
 
Thanks Pug. Not sure if I got I right or not as still got same problem.
Anyway just incase I didn't explain myself properly let me clarify.

The loco need to move to the track mark and then move forward to collect wagon B. However wagon A wont allow the loco to enter the siding to do so. (hope image shows what I mean)

EDIT: Ive noticed that the AI is not taking control of the junction. Ive rebuilt said junction with no effect. AI only seems to be able to take control of it is when I move the wagons onto another line


 
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Try to put a signal on the track between the junction and the cars.

See if the loco goes to the red singnal and stops there.
After that it should drive through the red signal and couple with the cars.

Because the cars are now on an unprotected track the loco won't move.

You can also put a buffer at the end of the track that will function as a RED signal.

Test it with visible signals, it's better to see what is happening.



(or do not use any singnal at all...)
 
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Ok. I've completely rebuilt all the track in the effected area. I've put visible signals on it to see what happens. Nothing. What the signals tell me is that the track ahead is not signalled - which is nonsense as there are 3 further visible signals beyond the first one. The message I got from the system (when you get the exclamation mark next to the driver) tells me its waiting for access to the junction - which is again nonsense as there is nothing near the junction. The loco was just not taking control of the junction. No apparent reason for it that I can see.
The only thing that seems to allow me to pass the junction - apart from removing the wagons at the end of the siding - was to put in an invisible junction half way down the length of the siding. With that in place it works as its supposed to.

Have to say I'm finding this frustrating. Could it be the track I'm using? (rail only as its running across concrete). I doubt that but who knows.
 
The signals are protecting the wagons and the locomotive under AI is unlikely to pass them. Try removing all signals between the locomotive's most forward point on the track and all the wagons you want to collect. I accept it seems odd not having signals protecting points but observing the arrangements at Westbury my local junction its not that unusual. Also ensure you do not have any direction markers blocking your paths. Peter
 
This has been around since the early days. Unlike the runaround command, which will pass the signal at red, all other commands wont. The signal sees an obstruction on the line ahead, the wagons.
 
Hi

Download Approach To Train from the DLS and use it with SetDCCThrottle and Couple Ahead which are both built in. They are all by atilabarut.

Go to the PLL website http://www.potteriesloopline.co.uk/ and download the Shedmaster package which will give you a number of excellent driver commands and rules, one of which is Control Junctions 3.

Use Control Junctions 3 to set the path into the siding followed by this sequence of commands:

SetDCCThrottle 0.4
Approach To Train 20 meters
SetDCCThrottle 0.28
Approach To Train 10meters
SetDCCThrottle 0.18
Couple Ahead

I usually put this sequence of commands into the Schedule Library so they can be used by any train.

These commands ignore signals and so will drive past the red signal. They also give a more realistic couple than the usual command. You may need to adjust the throttle values to get the result that you want.

Regards

Brian
 
Try using a special shunt signal in the path because some Trainz locos will pass over the red indicated shunt signal to a way-point marker.
There are are variety of shunt signals displayed in content manager.
 
Thanks all for the responses and help. Brian your suggestion helped a lot. Unfortunately it was coupling to the wrong wagons first (maybe I was not clear that I wanted to couple to wagons B first). However it did give me some thoughts to follow. Instead of using the couple ahead I halted the loco and moved it towards wagon B - altering the distance traveled towards wagon A first.
Problem I have now is now that I have collected wagon B it refuses to go back across the junction to move the wagon to its assembly point. The method you have given does not work in this case as it already has wagons in tow.
So I will look at using either the shunt signals as suggested above by davies_mike57 or maybe even interlocking tower. I was hoping to avoid visible signals but I guess I may not have much of a choice.
 
The one thing I have found with Trainz is that you should probably do complex switching yourself. I don't usually have switching done by the AI but it depends on how complex it is. If I do let the AI do switching, I make sure not to have any signals around. Without signals, the AI usually does couple to the cars then.
 
Hi

You need to set the two junctions using Control Junctions 3, followed by an "AutoDrivePastJunction" command (on the DLS by atilabarut) using the second junction as the target. Follow this with a change direction command followed by Control Junctions 3 to set the path to wagon B and then copy the couple commands from the Schedule Library. After coupling reverse the train direction again, set the junction direction followed by the couple commands again. Reverse train direction and set path to wherever the loco and wagons need to go. If you put these commands in correctly this will work.

The only way to get the AI to do exactly what you want is to take decision making away from it and spell out exactly what you want it to do. I know it takes a little longer to program the commands but it is worth it to avoid the frustration of wondering what it is going to do next. Any sequence of commands that are used frequently or by other trains are put into the Schedule Library so that they can be copied into a train schedule with just one command.

You have to remember when using these types of commands to set the path and direction of travel for the train. It doesn't automatically change direction or junctions like a Drive or Navigate to/via command would.

Have a look on the DLS for driver commands by "atilabarut" most of them are over 10 years old but will work perfectly in TANE and will give you greater flexibility than the standard commands. If you want a train to do its own decision making then look on the DLS for the conditional commands by "trev999", " Insert buff label", "Jump to label", "Set S-Variable", "Skip if session-variable" and "Wait Until S-variable V3" which will check values in variables and allow different routines to be used depending on the value in them.

Regards

Brian
 
just put a junction before the cars at the end such as invisible track and like a street junction hard to see., then leave the junction open to the invisible track and place your invisible signal...this will let the loco believe the track is not occupied and do what it needs to...
Dave =)
 
Can anyone shed any light on this issue please? It would be a pity to have to move the wagons to another location just because the loco wont complete its task.

Antony, I just made your set up in the mostb simplest form I could and it works perfectly to your requirements.

Region England.
Scale Full size.

Track T:ane, 1trk wood (It's the first one listed).

Locomotive. Gwr 45xx
Wagons. Gwr Workshop van, to be collected first.
Three other wagons, GWR Salvage van and 2 x Shunters trucks. These three are coupled to each other. placed wait at the far opposite end of the track to the Salvage van.

First. I Laid pair parallel tracks connect as per your diag. with both switches set for the ahead position.
At each end of the siding a set of buffers.
Protecting the three wagons a simple signal 2AH BR Post Round Head (operates Simple green/red) Positioned 150 ft from the junction. 50 feet toward the junction a track mark.
There are four more signals all same as above. Placed two at the ends of the "main line" Two so that I can be certain to have a green light showing..........
350 ft from the main line junction a track mark.

The loconotive is 100 ft from the junction and the following instruction provided through AI.
Drive to trackmark "main line"
The loco moves down the main line and away from the turnouts.

Drive to trackmark "siding".
Both sets of switches change and the loco sets off for the siding. Coming to a halt at the appropriate place and in front off a red signal.

Couple to "GWR Worshop Van"
At which turnouts change and the loco proceeds away from the red sig. towards the "Workshop Van" and couples to it.

couple to "GWR Salvage Van"
without hesitation loco sets out on that mission and compleats no problem.


The final request was for AI to drive to trackmark "main line"

Which it did. The whole operation was carried through without hesitation.

Note when asked to couple to the Salvage Van AI proceeds past a red to make the connection. No hassle no problem.

I end up back on the main line with in order "Workshop van, locomotive, Salvage Van and 2 x Shunters trucks".

Conclusion one of the components you are using is not compatible with what you are attempting.

Track or locomotive I think most likely................ :D
 
.....
Conclusion one of the components you are using is not compatible with what you are attempting.

Track or locomotive I think most likely................ :D

Thanks Parryjc. I had considered that there might be a problem with the track as I mentioned above. Never thought about the engine though so I shall test that out.
 
Hi

You need to set the two junctions using Control Junctions 3, followed by an "AutoDrivePastJunction" command (on the DLS by atilabarut) using the second junction as the target. Follow this with a change direction command followed by Control Junctions 3 to set the path to wagon B and then copy the couple commands from the Schedule Library. After coupling reverse the train direction again, set the junction direction followed by the couple commands again. Reverse train direction and set path to wherever the loco and wagons need to go. If you put these commands in correctly this will work.

The only way to get the AI to do exactly what you want is to take decision making away from it and spell out exactly what you want it to do. I know it takes a little longer to program the commands but it is worth it to avoid the frustration of wondering what it is going to do next. Any sequence of commands that are used frequently or by other trains are put into the Schedule Library so that they can be copied into a train schedule with just one command.

You have to remember when using these types of commands to set the path and direction of travel for the train. It doesn't automatically change direction or junctions like a Drive or Navigate to/via command would.

Have a look on the DLS for driver commands by "atilabarut" most of them are over 10 years old but will work perfectly in TANE and will give you greater flexibility than the standard commands. If you want a train to do its own decision making then look on the DLS for the conditional commands by "trev999", " Insert buff label", "Jump to label", "Set S-Variable", "Skip if session-variable" and "Wait Until S-variable V3" which will check values in variables and allow different routines to be used depending on the value in them.

Regards

Brian

My thanks to you again Brian. Using the methods you have given I can now successful collect all the wagons in their correct sequence.
 
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