Turntable and transfer table

Currently, railML 3 is missing a model for turntable and transfer tables. Which information are relevant / required for turntables and transfer tables:

• usable length of track
• topological connection with tracks (where can the train generally go)... <netRelation>
• location (coordinates)
• time needed for moving from one track to another one?... difficult to standardize, because it depends on the movement distance
• differentiation between turntable and transfer table, because the turntable can be used to turn vehicles in their direction while the transfer table cannot
• angle for a certain stabling track (in case of turntable)... where is the angle 0?
• limitations in maximum load
• connection between topology and functional infrastructure element (like with the switch branches...)

Links

• Forum discussion:
  • Torben Brand, 05.08.2025: https://www.railml.org/forum/index.php?t=msg&th=1081&goto=3685&#msg_3685
• Gitlab issues:
  • #683
• Wiki documentation

Proposed solution railML 3.4

Add new functional infrastructure element <turntable> to model turntables.

Add new functional infrastructure element <transferTable> to model transfer tables.

Both, <turntable> and <transferTable> have the same base datatype.

The usable length (in metres) of the movable track is defined with attribute @usableTrackLength.

Modelling turntables

The tracks, which are connected by the turntable, are modelled with an arbitrary number of child elements <connectsWithTrack>. The <connectsWithTrack> has a reference @trackRef to the related <track> element and an attribute @angle defining the relative angle between the incoming track and the outgoing track in a mathematical positive direction with values 0..359.

In addition, an arbitrary number of child elements <branch> links the turntable branches with the underlaying topology: The <branch> has a reference @netRelationRef to the topology element <netRelation> that connects the two <netElement> objects forming the navigable network. Actually, this information is redundant as it can be derived from the topology base of the referenced tracks.

Modelling transfer tables

The tracks, which are connected by the transfer table, are modelled with an arbitrary number of child elements <connectsWithTrack>. The <connectsWithTrack> has a reference @trackRef to the related <track> element and the attribute @offset defining the lateral distance between the incoming track and the outgoing track in meters, whereas positive values indicate an offset to the left and negative values indicate an offset to the right. Further, the additional attribute @needsChangeOfDrivingDirection (boolean) tells us if the locomotive needs to change its driving direction on the transfer table in order to reach the outgoing track.