## Description signalIS/isTrainMovementSignal is now an empty ambiguous container. ### Background There is a need to to distinguish between the physical and functional properties of the railway signals as well as represent schematic track plan by railML3 . ### Links * Forum discussion: * https://www.railml.org/forum/index.php?t=msg&goto=3217 * https://www.railml.org/forum/index.php?t=msg&goto=3225 * https://www.railml.org/forum/index.php?t=msg&th=937&start=0& * Torben Brand, 19.04.2024: https://www.railml.org/forum/index.php?t=msg&th=899&goto=3226&#msg_3226 (request for isLevelTransitionSignal) * Gitlab tickets * #533 * Wiki documentation: * IS:signalIS: https://wiki3.railml.org/wiki/IS:signalIS ## Proposed solution railML 3.3 `\\isTrainMovementSignal` will have additional `@type` attribute with enumeration **"main, distant, shunting, repeater"**. The definitions are as follows. `@type` attribute of `\\isTrainMovementSignal`: - **main**: signal with highest safety level for train movement authority - **distant**: this signal indicates the aspect of an upcoming movement signal but gives no movement authority on it own. - **repeater**: this signal repeats the aspect of a movement signal/the movement authority. - **shunting**: signal for degraded safety level for train movement (secondary to "main", but with more flexible operations) Combined signals will be modelled as separate infrastructure signals linked to the parent with `@belongsToParent`. `\\signalConstruction` will have additional `@mountedOn` attribute with enumeration **"pole, gantry, wall, ground, bufferStop"**. This child should belong to the parent of children signals. `@mountedOn` attribute of `\\signalConstruction`: - **pole**: The signal is mounted on a pole along the track - **gantry**: The signal is mounted above the track - **wall**: The signal is mounted on a wall - **ground**: The signal is mounted on the ground - **bufferStop**: The signal (typically a board like ETCS- Stop Marker borad) is mounted on a buffer stop that terminates a dead end track. New signal sub-type `\\isLevelTransitionSignal` will be introduced. It shall refer to the `\\etcsLevelTransition` element with an optional attribute `@etcsLevelTransitionRef`.