Ap Gradient Feature

Discussion in 'General Discussion' started by 749006, Jan 28, 2025.

  1. 749006

    749006 Well-Known Member

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    In the manual for the new AP Class 92 EP it mentions Gradients and the feature they have added.
    But I cannot get my head around the paragraph (my highlighting)

    "By default in Train Simulator Classic, only gradients of 1 in 185 or steeper have a gravitational effect on a train and this is only suitably realistic on gradients of approximately 1 in 125 of steeper. This means on gradients shallower than 1 in 125, the train does not experience the gravitational forces upon it than it should."

    Either I'm reading this wrong or the Blue text seems to contradict the Red text
     
  2. Andy L

    Andy L Active Member

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    Makes sense to me. If the gradient is less than 1 in 125 the core doesn't apply the correct acceleration / deceleration due to the gradient and if the gradient is less than 1 in 185 then no correction is applied at all. Less means closer to level not a smaller number after 1 in ....
     
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  3. fakenham

    fakenham Well-Known Member

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    Didn't really realise this effect in the core, a bit disappointing really. Haven't got the 92, so if the physics are correct now with that loco then that is great work. Hope other trains can be fixed.
     
  4. 749006

    749006 Well-Known Member

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    The new 92 EP pack is not out yet
     
  5. 749006

    749006 Well-Known Member

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    It says the "in Train Simulator Classic, only gradients of 1 in 185 or steeper have a gravitational effect on a train"
    So if the game is applying the effect why is AP applying something at 1 in 125 and steeper?
     
  6. Andy L

    Andy L Active Member

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    I don't read it that way. The correction is being applied for gradients less steep than 1 in 185 because the core doesn't apply any compensation. It's also applying a correction, presumably slightly different, for gradients between 1 in 185 and 1 in 125 because the correction the core applies in those cases isn't accurate. There's nothing in the piece you quoted to suggest that correction is being applied for gradients steeper than 1 in 125 because presumably what the core does in those cases is satisfactory.
     
  7. 749006

    749006 Well-Known Member

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    AP said "By default in Train Simulator Classic, only gradients of 1 in 185 or steeper have a gravitational effect on a train"
    How does the 1 in 125 come in to it as that is Steeper than 1 in 185
     
  8. Andy L

    Andy L Active Member

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    I've tried explain what I believe AP are saying and I suggest you take it up with them if it still makes no sense to you.
     
  9. 749006

    749006 Well-Known Member

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    I'm was just asking to see if anyone else knew what it meant
     
  10. tommydee

    tommydee Well-Known Member

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    It's meaning seems clear to me:
    1. Only gradients steeper than 1:185 have any effect in TSC.
    2. Only gradients steeper than 1:125 have an accurate effect in TSC.
    3. Therefore any gradients less steep than 1:125 have an inaccurate or no effect in TSC.​
     
    Last edited: Jan 30, 2025
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  11. 749006

    749006 Well-Known Member

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    Ok - that helps. Me getting old.
     
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  12. maxtedrw

    maxtedrw Active Member

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    So I've wound my neck in a bit. I misread what they are saying which is that the physics of gravitation is duff at gradients of less than 1:125. Where I might disagree is that gravity doesn't have any effect at gradients of less than 1 in 185. To that end my original post still stands. On track that where the height adjustment tools at each end of the track are showing an identical height to two decimal places ( all the tool is able to show ) you can see, when the track is highlighted in editor that it can have, for instance, a gradient of someting like 1 in 650943784 or some such shallow number. What is happening if one examines the track.bin file is that each end of the track differs in height by at least the third decimal place and is actually often much more different than that. The track setting height actually rounds up or down the height to two decimal places. Even on an apparently level section of track where the height adjusters are identical this slight 1cm or less variation in height is sufficient to cause light and short wheel base narrow gauge wagons to roll or to "creep" in the direction of the slope. The only way to eliminate this and get a true 1 in 0 gradient after track laying and manipulation is to edit the tracks.bin file. I discovered this as part of my trying to solve the total misbehavior of my skip wagons. In the end I had to manually edit quite a few sidings to make sure they were absolutely level to prevent "skip creep" - a horrid disease I wouldn't wish on my worst enemy
     
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