[StevenMasters]

Is there any interest for drawbridges now that we have turntables and transfer tables?

This would be a more involved process as it would require some linkage to the signal system. Here is a possible entry for the drawbridge that follows the current definitions for the turntables.

Drawbridge(
 WFile ( "w-######+######.w" )
 UiD ( # )
 XOffset ( # )
 YOffset ( # )
 ZOffset ( # )
 Name ( "" )
 Animation ( "SWINGSPAN" )
 AnimationTime ( seconds )
 SoundFile ( "filename" )
 DefaultClosed ( "true/false" )
 ClosedCLEAR( #
  RadioFile ( # "filename" )
  SignalId ( # )
  ...
 )
 ClosedSTOP( #
  RadioFile ( # "filename" )
  SignalId ( # )
  ...
 )
 SignalDelay ( seconds )
)

WFile()/Uid()/XOffset()/YOffset()/ZOffset() - would be the same as turntables.

Name() - for display purposes (those pesky humans).

Animation() - as with turntables, the name of the part to be moved.

AnimationTime() - how long should the span take to move from open-closed.

DefaultClosed() - is the shape set up to be closed by default.

ClosedCLEAR() - list of signals to be set to CLEAR when closed. All signals have a unique TrItemId() number which would allow for the drawbridge state to be linked to the signal system.

RadioFile () - cab radio message to play where # is:
<0 - seconds before animation starts
0 - as animation occurs
>0 - seconds after animation ends

ClosedSTOP() - list of signals to be set to STOP when closed.

SignalDelay() - after closing/opening, how long before signals are set to clear.

[ebnertra000]

That would certainly be interesting to have. It may not necessarily need to have a direct connection to a signal system for a couple reasons:

1. It may not be protected by signals. Most likely, this would be the case on some lightly used branch line where only stop signs or something similar are present.
2. If you were to set up some kind of track node in the span (hazard-to-node method?) and then have the drawbridge use that to close the line to traffic, it wouldn't have to access the signal system to drop signals. I'm not sure if that would work, though, as I've only seen that method used for diamond crossings

[Jonatan]

MSTS has downloadable opening bridges that were built as crossings and activated when the train approached them.

[StevenMasters]

ebnertra000, on 05 September 2017 - 07:24 AM, said:

That would certainly be interesting to have. It may not necessarily need to have a direct connection to a signal system for a couple reasons:

1. It may not be protected by signals. Most likely, this would be the case on some lightly used branch line where only stop signs or something similar are present.
2. If you were to set up some kind of track node in the span (hazard-to-node method?) and then have the drawbridge use that to close the line to traffic, it wouldn't have to access the signal system to drop signals. I'm not sure if that would work, though, as I've only seen that method used for diamond crossings

1) I was personally thinking of INFO signals. These would be buried signals that can be referenced by the signal scripts.
2) Not sure about the hazard-to-node method but it sounds complicated.

Jonatan, on 05 September 2017 - 09:01 AM, said:

MSTS has downloadable opening bridges that were built as crossings and activated when the train approached them.

I have made some of those but they don't allow for water traffic.

[roeter]

From the 'flags' I can see where the ideas and, in particular, the various definition fields come from.
But, on this side of the big water things are a bit different.
Moveable bridges are operated to a fixed timetable, integrated in and linked with the train timetable, such that they have fixed opening times and minimal and maximal open periods. Obviously, no trains are booked to pass the bridge at these times. These timings are so hard that a late-running train will have to wait while the bridge is opened according to its set times. And they are most definitely integrated in the signalling (and those are certainly not just info signals).

It can be done, but if done it should be properly set up as an integrated and proper working object, and not as just a gimmick.
A similar setup as a turntable is not quite enough. As things are, AI trains cannot use turntables. But moveable bridges would, ofcourse, need to work on AI trains. It would be a pretty dismal gimmick if AI trains just ran accross an opened bridge as if it wasn't there.
In that sense, the existing MSTS bridges which work as a level crossing are completely unrealistic - the train approaches under clear signals at full speed and the bridge closes just as the train is almost reaching it. That is a situation that would never ever be allowed in this part of the world.

The route editor would have to be adapted to place the bridge such that it is integrated in the route's .tdb file, as bridge item, so it can be properly linked to the track control and signalling. This could be done in a similar way as road-crossings. This is required to ensure the bridge does not open when there's a train on it or a route has been cleared over the bridge for an approaching train, and, in reverse, ensures trains will stop if the bridge is open. Signals also need to be held at danger before the actual bridge opening such that routes will not be cleared for approaching trains if these trains cannot pass before the required opening times. This would require a approach time definition, either in the bridge definition or in the timetable.
To make it possible to integrate such bridges within a timetable - with setting fixed opening and closing times - a 'NAME' field would be required which would need to be unique (per bridge) such that it can be referenced in the timetable.

Radiofiles should be optional - no cab radio is used here for bridge openings as signals control the traffic.

Most of this could be done though it does require a fair amount of programming. Adapting the route editor is probably the biggest obstacle.

Regards,
Rob Roeterdink

[Jovet]

I love this idea. On this side of "the big pond" bridges are opened and closed on demand, usually by cooperation among dispatchers. The animated "LevelCr" bridges can be made to lower minutes before train arrival but they're just not the same as a proper solution with signal system interaction.

[SP 0-6-0]

Hi all, Has this been made to function?

Robert