Questions About Super-Elevation, Speed Limit Setting on Routes, Animated Switches

[JonMyrlennBailey]

Let's use my TANE project route, Avery-Drexel for example.

This route is by TUME. By default there are no animated switch points, no super-elevation and built-in speed limits seem too high for some sections with tight turns to be realistic.

How does one add super-elevation to a TANE route originally without it?
Can the track parameters be edited for super-elevation or is track replacement necessary?

How does one get animated switch points into a route without it?

How can I determine speed limits for sections of the route that are realistic and are IAW American railroad standards based upon curve radius, whether super-elevation is present, grade, junction blocks, main line or yard switching or other criteria. If the speed is too high for a sharp curve I can almost "feel" the jolt as the camera turns suddenly.

In Surveyor, one can modify speed limits with signs or invisible triggers. One can also get the curve radius in Track mode, Advanced.

 

[JCitron]

Super elevation is added by right-clicking and adding the parameter to that portion of the track between the two spline points. Other than that, I have not tried it to help any further.

Animated points are available on the built-in T:ANE Track such as the Jarrah or Oak, both of which look pretty good too and not too foreign-looking which is a problem with some track because in other countries the equipment is a lot lighter so ties are spread out farther and they're thinner. Australia, like the US, has heavy locomotives and freight cars which need heavy track.

John

 

[JonMyrlennBailey]

Ok, John: I tried Jarrah track, shiny rail tops, but looks good. What is the recommended SE degree and SE limit one should use on track edit parameters? All the manual says is that track SE can be adjusted by a certain number of degrees.


Is there a good website that has track-laying standards for real American railroads? I think it would be rather fun to make a Trainz route conform to realistic RR standards as much as possible. I need expert insight from the real American RR community.

 

[JCitron]

As I said, I have not played with that. In the Trainz Dev forum, that you have read-only access to, there's an interesting discussion on this subject. You might want to look at that. To be honest the math makes my eyes glaze over. I haven't seen this stuff since my college days.

There are some good Google books available on this subject some of them are 100-plus years old, which would be when the railroads were first built anyway. It's hard to believe they did this surveying with rope, chains, and lanterns. The famous Hoosac Tunnel in western Massachusetts was built this way. When both sides met, they were only off a few inches!

John

 

[RPearson]

Let's use my TANE project route, Avery-Drexel for example.

This route is by TUME. By default there are no animated switch points, no super-elevation and built-in speed limits seem too high for some sections with tight turns to be realistic.

How does one add super-elevation to a TANE route originally without it?

Edit track vertex properties in surveyor.

Can the track parameters be edited for super-elevation or is track replacement necessary?

AFAIK all spline track in TANE - except the old "chunky mesh" track - can have superelevation added as per my comment above.

How can I determine speed limits for sections of the route that are realistic and are IAW American railroad standards based upon curve radius, whether super-elevation is present, grade, junction blocks, main line or yard switching or other criteria. In Surveyor, one can modify speed limits with signs or invisible triggers. One can also get the curve radius in Track mode, Advanced.

Jon with respect to curves, SE and allowed speed there are 2 threads in the dev froum and 1 more that I know of in the kickstarters forum that address SE specifically or in part. Some of the discussion is a bit heavy on the math involved and starts from 1st principles or German rail stds or US Federal regs. We've presented formulas and tables to assist route builders in selecting appropriate SE values to use. We've tried to simplify the problem by relating it to allowed speed if you want to gloss over some asects of it but formulas are presented so you can do the math and calculate SE values based on German or US standards. We've also pointed out a few bugs and N3V have adressed or are addressing them in the current test builds. You have to realize that anything discussed or presented there is very much a WIP so be advised. But there's enough there to design your own curves if necesary. Everything except maybe compensated curves on grades which is another subject.

For info on speed limits elsewhere on routes I suggest you do due diligence and research the individual railroads you're modeling for their standards along with other sources.

Here's the links to the references.

LINKS:
1) http://forums.auran.com/trainz/showthread.php?120490-Superelevation

2) http://forums.auran.com/trainz/showthread.php?121567-So-do-we-have-superelevation-or-not

3) http://forums.auran.com/trainz/showthread.php?120063-Procedural-Track-FAQ

If the speed is too high for a sharp curve I can almost "feel" the jolt as the camera turns suddenly.

The jolt you feel going into a sharp curve isn't necessariy the effect of the wrong speed. Going from tangent (straight) track into a curved section involves (in mathematical terms) a discontinuity in the 1st derivative of the function describing the track location on the ground. It's this discontunity you feel since this is what we see and sense as "smoothness" in the track. Real track work uses a transition curve or easement between the tangent track and a fixed radius curved section. While the Trainz track spline will not show an actual discontinuity in the 1st derivative the rapid change it shows gives you a similar effect. Normally both SE and easements are required for real track work and run-in and run-out of the SE is combined into the easement portion of the track. The run-in and out are required so we have a "smooth transition" in the change in rail height due to application of SE.

How does one get animated switch points into a route without it?

Currently in TANE animated points, auto placement of frog and wingrails are provided by using proceedural-track. In the past you could manually add frogs and wing rails and points that moved based on switch setting. Fixed track could also be used to make junctions that had these features. The number of routes using these kind of indicates the problems and difficulties associated with them. Going fwd I personnally think proceedural-track holds a lot of promise. Making the individual parts isn't much more difficult than making current track splines. The config that references the individual parts has new tags and requires some new learning but if you can cope with the old track you should be able to get a handle on the new proceedural-track. As far as adding it to a route. It is laid just like the old track splines.

Bob Pearson

 

[rrfoose]

Say one has a 90 degree turn. One spline point at each end adjoining the straight tangent, then 1 spline point in the middle of the curve to make the curve properly aligned. Should we only be applying the superelevation to the spline joint in the middle of the curve? Or all 3 associated joints? I've seen in other threads that a bank angle of 5 and limit of 0.1 works "best" to be fairly realistic.

 

[JonMyrlennBailey]

Mr. Pearson:

The trouble is in TANE Surveyor, only curve radius values, not degrees, are given for curves.

What I want to do in my cloned Avery-Drexel route is to not alter any existing curves or grades in the whole track composition.

Starting with the preexisting track on the route, I want to add the element of;

-correct speed limits
-correctly-applied super-elevation based on the exsiting curves and the correct set speed limits
-correctly-applied switch points animation

I understand track replacement is necessary because exiting track does not incorporate these parameter edit ability for SE and junction animation but track assets can easily be replaced 'wholesale', not necessarily spline point to spline point.

I KNOW the RADIUS of my curves.
I KNOW the gradient of my track.

The unknown parameters to determine remaining are:

-correct super elevation for EXISTING curves
-correct speed for these curves

Experience driving trains into the sharp curves [some as sharp as 550-foot-radius determined by comparing them with the Google Earth birds-eye map of the this subdivision and using the ruler to take measurements] of the Tehachapi Mountains in the Mojave Sub in TS12 at various speeds has convinced me that the perceived impact of turning is less dramatic the slower the train travels into these curves easement or no easement. The camera position looking out the cab windshield forward does not seem to shift as suddenly the slower the train goes into these turns. Those curves were tight and likewise the built-in speeds for those were a safe-and-sane 25 MPH and that section of track had about +/- 2% grade most of the way.

 

[RPearson]

Jon I'll try replying one or two responses at a time so here goes:

Mr. Pearson:

The trouble is in TANE Surveyor, only curve radius values, not degrees, are given for curves.

...

If you took the time to read thru the threads I referenced above, you would know that the radius of the horizontal curve, in meters, is all you need when setting up the new SE properties - you don't need degree of curvature or degrees of central angle or degrees of anything eles. If something is missing from the references I gave you let me know as I think it covers everything you need. If you find the math a bit much as many do, geophil and I provided some tables that at least would give a good sense of SE based on the speed posted for the curve. The formulas I provided allow calculation of the missing part if any 2 of the 3 variabes are known for any who want to do the math themselves.

Bob Pearson