[Coolhand101]

When testing my trainsets for traction performance, i have the 'advance adhesion model' checked and 'MSTS compatible' level for 'Adhesion factor correction and random change'.

My secondary question is, does the 'adhesion random change' at the default of 10% have an effect on traction performance ?

My primary question is, when checking "Adhesion proportional linked to rain/snow/fog", the adhesion level goes to 'hard'. However, with weather set to clear and summer, i can lose up to 5 mph when testing on a 1% grade.

Do i need to lower the 'adhesion random change' to 0% 'normal', to avoid the speed lost with weather set to clear?



Thanks

[Hamza97]

There is some kind of bug in adhesion model, if you have kept the extended HUD opened on force information you will see that during any weather other than clear, the the green coloured motive force graph remains constant to TE developed by locomotive and drops linearly as defined in tractive curve,

However if weather is set to clear you will notice that the motive force fluctuates up and down and we have to press sander for 1-2 seconds and again the motive force again becomes constant, but again after 3-5 seconds it starts to fluctuates and we have to again press sander to get constant motive force. This continues as long as you drive.....

[Coolhand101]

Hamza97, on 12 December 2015 - 08:40 AM, said:

There is some kind of bug in adhesion model, if you have kept the extended HUD opened on force information you will see that during any weather other than clear, the the green coloured motive force graph remains constant to TE developed by locomotive and drops linearly as defined in tractive curve,

However if weather is set to clear you will notice that the motive force fluctuates up and down and we have to press sander for 1-2 seconds and again the motive force again becomes constant, but again after 3-5 seconds it starts to fluctuates and we have to again press sander to get constant motive force. This continues as long as you drive.....

Is this with all traction ? I may of overlooked this as i have added resistance notches and field diverts to 90% of my trainsets, so my motive force graph looks like 'see-saws' and 'humps' Plus 50% of my EMUs have the power car in the middle of the consist, which will not show any graph as the front coach has zero power.

Thanks

[Hamza97]

Yes, It happens with diesel and electrics but can't tell about steam locos as I don't drive them....

BTW What is resistance notching and how do we add it..?? All my locomotive's have fixed (32) notches and diesels have 8.... :)

EDIT - Oh... and they all have ORTSAdhesion parameter added to .eng files....

[Coolhand101]

Hamza97, on 12 December 2015 - 09:59 PM, said:

Yes, It happens with diesel and electrics but can't tell about steam locos as I don't drive them....

BTW What is resistance notching and how do we add it..?? All my locomotive's have fixed (32) notches and diesels have 8.... :)

EDIT - Oh... and they all have ORTSAdhesion parameter added to .eng files....

Just some tweaks to the "ORTSTractionCharacteristics!" table.

I haven't touched my electric locos in OR as yet. They have 38 resistance notches, i don't think there's anyway to 'hold' these notches. In MSTS, i actually had 38 notches in the engine controller throttle setting.

With the weather changes in activity mode, i need to fully understand the best adhesion levels and percentages. It's no good losing speed on certain levels, on a dry and clear day.

I keep on forgetting about the 'ORTSAdhesion' parameter. I know when i first tested it, i didn't notice any changes to adhesion.

Thanks

[Hamza97]

I think we two are only interested in this (adhesion and physics) part of Open Rails......

Anyway, No offense to anybody but the way whole adhesion thingy is calculated in OR should be revised.

Currently as you said I also don't see any difference when using ORTSAdhesion parameter.

One of parameter on FORCE information screen is this
Wheelslip% - I actually don't know what it indicates. Ideally this should be zero all the time and should only increase when wheel SLIP occurs.

What we need is something like this
MaxAdhesion%
AvailableAdhesion%
Wheelslip
.... and other parameters which are there

The MaxAdhesion parameter should describe the maximum adhesion that can be developed at that spot and should ideally depand on track conditions.

The AvailableAdhesion% should describe maximum adhesion that particular loco can develop as defined with ORTSAdhesipn parameter.

And lastly the Wheelslip% should only increase when there is Wheelslip and not all the time

This is my suggestion regarding adhesion and physics in Open Rails. And lastly if anybody is offended by above post then apologies......

[copperpen]

IIRC the current adhesion model only uses one "big wheel" and has nothing to do at all with the actual number of driven axles on a locomotive or multiple unit. I currently have my adhesion slider at 100%, the random change factor at 0% and weather effects ticked. My visual force HUD indicator does not fluctuate, but is smooth, unless wheelslip occurs. I also do not think that clear weather has any bearing on performance on grades, at least I do not see any more slowing in clear than I do in wet or snow.

[Coolhand101]

Hamza97, on 13 December 2015 - 04:28 AM, said:

I think we two are only interested in this (adhesion and physics) part of Open Rails......

Anyway, No offense to anybody but the way whole adhesion thingy is calculated in OR should be revised.

Currently as you said I also don't see any difference when using ORTSAdhesion parameter.

One of parameter on FORCE information screen is this
Wheelslip% - I actually don't know what it indicates. Ideally this should be zero all the time and should only increase when wheel SLIP occurs.

What we need is something like this
MaxAdhesion%
AvailableAdhesion%
Wheelslip
.... and other parameters which are there

The MaxAdhesion parameter should describe the maximum adhesion that can be developed at that spot and should ideally depand on track conditions.

The AvailableAdhesion% should describe maximum adhesion that particular loco can develop as defined with ORTSAdhesipn parameter.

And lastly the Wheelslip% should only increase when there is Wheelslip and not all the time

This is my suggestion regarding adhesion and physics in Open Rails. And lastly if anybody is offended by above post then apologies......

I believe the wheelslip percent before the wheelspin is actually detected, is some form of wheel 'creep'.

When it rains, the adhesion is much lower, and this will cause the wheels to spin slightly quicker. Now this 'lower' spin will not cause severe lost in speed and will cause no danger of damaging the rails, hence no wheelslip light is detected.

I once saw a video of class 87 with 11 coaches, lose 10 mph( 90 to 80 mph ) all the way up beattock bank( 10 miles of 1 in 75/80/88 ) in the rain, without the wheelslip light illuminated. On another run, the same train, was stuck at 75mph, and the wheelslip light was on.

Also i'm sure you can change the wheelslip threshold, so the wheelslip light will become illuminated at a lower percent.

The adhesion factors and settings, in the options menu, play a great role in the wheelslip percent changing.

Someone with greater knowledge than me in this department, could explain this in much more detail or any corrections, for this percentage of the wheelslip.

Thanks

[Coolhand101]

copperpen, on 13 December 2015 - 06:41 AM, said:

IIRC the current adhesion model only uses one "big wheel" and has nothing to do at all with the actual number of driven axles on a locomotive or multiple unit. I currently have my adhesion slider at 100%, the random change factor at 0% and weather effects ticked. My visual force HUD indicator does not fluctuate, but is smooth, unless wheelslip occurs. I also do not think that clear weather has any bearing on performance on grades, at least I do not see any more slowing in clear than I do in wet or snow.

My settings for the 5 mph lost in speed in clear weather was :

adhesion slider at 130%
random change factor at 10%
Adhesion proportional linked to rain/snow fog ticked.

My Class 455 EMU can attain 55 mph on a 1 in 100 bank. With Adhesion proportional linked to rain/snow fog ticked, the EMU could only attain 50 mph.

Untick, it was back up to 55 mph. My test route does climb for about 8 miles at an average of 1 in 100, could altitude effect the adhesion with the 'Adhesion proportional linked to rain/snow fog' ticked ?

Or is it the 'random change factor' set at 10%, i left this as it is the default setting?. Makes sense as 50mph plus 10% is 55 mph( just a guess on my problem ).


Thanks

[Hamza97]

I have top slider at 100% and bottom at 0% with adhesion proportional to rain/fog/snow. I have set my ORTSWheelslipThreshold equal to adhesion of particular locomotive.

I will post some pictures of fluctuating motive force and constant motive force graph...

BTW what is ORTSTractionCharacteristic...??