Push/Pull Operations

[Driver_Col]

Does anyone know why an AI train (loco + carriages) would perform differently depending on whether it is in push or pull mode?

Example:

Traffic from location A to B has a very direct and uncomplicated route. Given no other traffic, a push/pull set with loco pulling will take it without problem. However, when the loco is pushing, it reverses to the first signal behind it......... hesitates ..........then proceeds appropriately.

The fact that it performs fine when in pull mode indicates to me that there are no problems relative to signals and points relative to track spline positions. Setting all points to "green" makes no difference.

So ............ why would it reverse to a prior signal, and then change direction again and proceed as it should have done in the first place?

Why is it unclear how to get from A to B only when the carriages are leading?

Why is this thing taking up so much of my time?



Colin.

 

[Driver_Col]

I just had a thought (it happens on occasion):

Maybe the instruction is always "processed" by the loco. In my scenario, the loco is facing forwards (chimney first).

So when in pull mode, the loco is as per normal with chimney first.
When in push mode, the locos front (chimney end) is facing the wrong way, and therefore it's initial analysis as to how to get from A to B results in the loco moving forwards (train therefore moving backwards) until it sorts itself out.

Make any sense to you loco and rolling stock creators????



Colin.

 

[fran1]

Col,
Use run round extended command. Then loco is always at the front. It moves the driver from 1 loco to the one at the opposite end.
Ahh, your not using push pull as I thought, loco +DVT.

 

[stagecoach]

Because the engine is the lead it will continue in that direction until it clears the station, the station is still in control of the train at this point. Try the change direction command after the load or wait then change direction.

 

[Driver_Col]

Col,
Use run round extended command. Then loco is always at the front. It moves the driver from 1 loco to the one at the opposite end.
Ahh, your not using push pull as I thought, loco +DVT.

Hi Fran. Yes I think you got the scenario. I have loco at one end, and carriage with driver cab at other.

:wave:

Colin.

 

[Driver_Col]

Because the engine is the lead it will continue in that direction until it clears the station, the station is still in control of the train at this point. Try the change direction command after the load or wait then change direction.

Good thought............but I am not using interactive stations so must fall back to the loco orientation dictating how it interprets instructions.



Colin.

 

[tmz06003]

I had problems testing a class 47/7 mk3 set and DBSO at the other end, under AI control the loco didn't respond correctly when changing direction as it had coaches in front of it! I did have some success changing the engine from 0 to 1 in the config of the DBSO, this seemed to work.

 

[JCitron]

I've had this issue too.
This is what I found:

Using the MetroNorth and MBTA Commuter Cab cars, and the AI drivers skip stations, backup, and get lost and stuck on the wrong tracks, etc.

If I use the old NYC/MN Pullman cars, everything works fine. I can use those as cab cars without a hitch.

I even setup a push-pull using an F7 as the locomotive pulling and pushing Budd RDCs, which is not unprototypical. The MBTA did this for about 10 years before they replaced them with Horizon cars. Anyway this worked fine as well.

I tried the suggested change direction command, and this was not reliable.

Weird...

John