(English) Some questions about changing height of track and gradient

    I'm currently designing a route in Sweden where I have used SRTM 30m data to get "better" topology. Unfortunately the starting station DEM data was slightly incorrect so I played my tracks about 5m higher than they are in real life. This would not be a problem if the whole route was raised 5m but I noticed later when I had built about 10km of track that only this station was wrong and so I needed to have higher gradient than in real life.


    1. I would like to move all of the track in the whole route 5 meters lower, is this possible? It seems like it would be possible in theory, just go over all track coordinates and subtract the Z-coordinate 5 meters (or vertical coordinate, seems like this is Y in TS2020).


    2. I have pretty good gradient data for my route like this: km xx.x-yy.y: 5 per mill up etc. Is there a better way to assign a piece of track a specific gradient (such as 0.005) instead of having to drag the gradient marker up (which is quite inaccurate and tedious)?


    3. When the gradient changes, has anyone found a good "gradient change per meter" that doesn't cause an unrealistic bump in the cab?


    I checked the Moselbahn and it seemed like a change from 0.0 to 4.0 per mill was done in sections of about 5m for every 0.5 per mil (so 0.0, 0.5, 1.0, 1.5, 2.0, etc each 5 meter). But I couldn't see any gradient markers, maybe this is deleted when you open up a route that you didn't make in the editor. But I wonder if the gradients were changed manually or with the "smooth gradient"-tool?


    4. I noticed that the "smooth gradient"-tool is kinda tricky/buggy. If I have for example 0.0 grade that changes to 8.0 per mill grade and I mark some track before and after the change in gradient sometimes after smoothing the grade goes up then down then up, rather than slowly going up. Is there a correct way to use the tool?

    Hello


    1)

    I wrote a script a long time ago for this purpose.

    I cannot publish it because it is a client side script which needs to run on a specific server. If you want to change the height of all tracks, I need your "tracks.bin". I will then try to lower the z-coordinates by 5000 mm (=5 metres).

    Please keep in mind:

    - all track infrastructure objects are lowered, too: signals, magnets etc. Every object with a track link.

    - all dead end sidings needs to be investigated afterwards, because very seldom the end geometries of the track object tends to move away from the proper end. This needs to be corrected afterwards in the editor by grabbing the track with the mouse and release again with a right click of the mouse (means: cancel). This problem with the moved end geometries will always happen if you "serz" the "tracks.bin" with the "serz.exe". This is not an issue caused by my script.


    2)

    I never used the gradient markers. I always typed in the gradient into the text field on the left.


    3)

    A good value is dependend from the current max speed.

    A long time ago the "smooth gradient tool" wasn't available and you was in a need to build small segments. I myself used 0,2‰ change per segment of (vMax)/20 metres of length, f.e:

    VMax 160 kmh = 8 metres segment length

    This principe was used by me on the route Hausach/Konstanz-Villingen and partially by me on the route Freiburg-Basel.


    The gradients on the route "Rollbahn"(Münster-Bremen) were made primary with this tool. A lot of experiments and testing was needed before to use it properly while building this route. But I think the result is pretty nice.


    The route "Moselbahn" used a similar principe with slightly different values and was also built before the "smooth gradient tool" was implemented by DTG.




    4)

    This tool works best if you prevent welding points (small red triangles) in this area.

    Egal, wie weit Draußen man die Wahrheit über Bord wirft, irgendwann wird sie irgendwo an Land gespült.

    Einmal editiert, zuletzt von Prelli ()

    Feel free to send me your tracks.bin via private message, preferably as a compressed archive.

    To confirm this: Lower all tracks and track infrastructure by 5000 millimeters?

    Egal, wie weit Draußen man die Wahrheit über Bord wirft, irgendwann wird sie irgendwo an Land gespült.

    I've sent you a PM. Thanks again for all the help!


    I have two follow up questions:


    1. Do most commercial routes use SRTM/DEM data or a different format or an entirely different process?


    2. I usually struggle with how to end a curve and transition to straight track when using easements and following the Google-maps overlay. This is because the straight track indicator is so short it is very difficult to see if it is slightly misaligned until you start laying the straight track. Usually I try to line up the straight purple indicator but then oftentimes have to split the curve at the end and retry until I get it "perfectly" aligned. Is there a better process than this?

    I lowered the tracks and made 2 versions as required each with a different offset.

    Good luck


    1.

    Afaik all routes use either SRTM or ASTER2 or a combination.

    There are different versions of quality available. I made the best experiences with DEM from http://www.viewfinderpanoramas.org/

    The data from there is used f.e. on the routes Münster-Bremen, Freiburg-Basel and Hausach/Konstanz-Villingen.


    2.

    I usually build a very sharp pointed mountain (16m x 16m x 100m Height) in the distance which helps me to align the tracks properly.

    This work -at least for me- pretty nice.


    I have no other solution for this, which is faster and more convinient, except trying.

    Egal, wie weit Draußen man die Wahrheit über Bord wirft, irgendwann wird sie irgendwo an Land gespült.

    Thanks for the info!


    If you don't mind, I have two other questions:


    1. I hear conflicting recommendations about using track rules, one is that you should only have one track rule per connected railway and one is that you "will not get far with only one track rule". My plan was to make my own track rule for the route so I can control stuff like superelevation/distance between tracks etc specific for the route I'm building (in Sweden). If you should have more than one track rule, what would be the reason for this?


    2. I like the look of the DBtracks but I can not find a download link, I've only seen them from Trainworks updates but they don't seem to come with the asset folder, simply just changed out tracks. Are these still available for download?

    You're welcome.


    1.

    Different values of maxspeed require different values for the superelevation.

    If you have a radius of 1000m with a maxspeed of 80 kmh you will probably want a noticeable but weak superelevation.

    If you have a radius of 1000m with a maxspeed of 160 kmh you will probably want a remarkeble and very heavy/strong superelevation.

    Therefore most route bulders use several trackrules for different maxspeeds.


    Just take a look into the assets folder of your favorite route (regarding proper and smooth track building and superelevation) , if its NOT from DTG/Kuju/RSC you will probably find a whole bunch of these trackrules.


    2.

    I never used the DBTracks. So I cannot help you.

    Just try to find them in the download area.

    Egal, wie weit Draußen man die Wahrheit über Bord wirft, irgendwann wird sie irgendwo an Land gespült.

    Einmal editiert, zuletzt von Prelli ()

    So there is no "danger" in creating a piece of track with one trackrule (f.e. vmax = 80) and then connect it to another piece of track with another trackrule (f.e vmax = 120)?

    No, there is no "danger".

    It is a good style ("Railequette" or "Knigge for Railworkers" :ugly:) to make a hard cut between the trackrules (red triangle).


    Just explore some of your routes in the editor.

    Egal, wie weit Draußen man die Wahrheit über Bord wirft, irgendwann wird sie irgendwo an Land gespült.

    Thanks, both Prelli and Rschally!


    I just have three follow up questions (that I can think of right now at least):


    1. What does "curve to angle percent" mean in the track rules blueprint?


    2. Just to confirm a max vertical rail displacement of y mm would give a "Max cant angle degrees" of arctan(y/1435) for normal track gauge?


    3. If we go back to this answer:


    "Different values of maxspeed require different values for the superelevation.

    If you have a radius of 1000m with a maxspeed of 80 kmh you will probably want a noticeable but weak superelevation.

    If you have a radius of 1000m with a maxspeed of 160 kmh you will probably want a remarkeble and very heavy/strong superelevation.

    Therefore most route bulders use several trackrules for different maxspeeds."


    The railway you are trying to simulate probably has a maximum cant (I think in Europe around 150-160mm but maybe there are some exceptions). Usually there is also a maximum lateral acceleration allowed, which will depend on the cant, curve radius and speed.


    In Sweden they use the following equation: R >= 11.8 * v^2 / (cant + cant deficiency). Take the 160 km/h at 1000m radius, would you create the track rule so that you need to use yard-type for this or perhaps you have passenger minimum = yard minimum? Or yard can exceed comfortable acceleration?

    Hello again


    1

    This value defines the length and curvature of the track transition curve.

    There are several formulas in use.... every route builder has its own preferences.

    Some use:

    MinRadius/10

    or f.e.

    TAN(MaxCantAngleDegrees/360 * 2 * Pi) * MinRadius


    2.

    The MaxCantAngleDegree should not exceed 7.15° (=180 mm) in germany

    ARCTAN(180/1435) / (2 * Pi) * 360


    3.

    Why would you use a yard trackrule for a 160 km/h main line or vice versa?

    I don't really understand the question.


    All formulas are in "radian" not "degrees"... ready for excel ;)

    Egal, wie weit Draußen man die Wahrheit über Bord wirft, irgendwann wird sie irgendwo an Land gespült.

    2 Mal editiert, zuletzt von Prelli ()

    I think in Sweden the max cant is 160mm so MaxCantAngleDegree = 6.36 deg


    "Why would you use a yard trackrule for a 160 km/h main line or vice versa?"


    It was more to find out how the system worked. If you define a 160 km/h track rule, then the minimum radius should be the minimum radius that trains can travel, with max cant, right? So then Passenger and Freight type would have the same minimum radius I presume? (otherwise for example passenger will give less cant)

    It is possible to spezify in the main-Line Trackrule in the Yard section a smaler radius und the max Speed Tolerance ,

    e.g.:

    <MainLineTrackLimits>

    <iTrackRulesBlueprint-sCurvatureLimits>

    <MaxSpeedTolerance d:type="sUInt32">184</MaxSpeedTolerance>

    <MinRadius d:type="sUInt32">1015</MinRadius>

    </iTrackRulesBlueprint-sCurvatureLimits>

    </MainLineTrackLimits>

    <YardTrackLimits>

    <iTrackRulesBlueprint-sCurvatureLimits>

    <MaxSpeedTolerance d:type="sUInt32">50</MaxSpeedTolerance>

    <MinRadius d:type="sUInt32">100</MinRadius>

    </iTrackRulesBlueprint-sCurvatureLimits>
    </YardTrackLimits>


    (Speedtolerance value = Speed + 10% to 15% )


    using of this values:

    klick on the Track, then Change the values in the right Flyout, Speed 40 , Linetype Yard.

    So you can lay a switch with 40km/H with the Mainline Trackrule, Ist a good practice to use the same Trackrule and Track for a switch.

    then continue laying yard-tracks with your Yard-Trackrule.

    Keine Hilfe und Auskunft per PN, da meist von allgemeinem Interesse. Diese Fragen bitte im Forum stellen.

    Thanks. I'll have to experiment with the track rules.