How-to Monitor Seabed Collision Avoidance
Seabed Collision Avoidance Monitoring is intended to warn if there will be a collision with the seabed / terrain ahead within a certain time.
E.g. for a deeptow towfish, based on current towfish 3D position, speed over ground and course over ground the function tests to see if there will be a collision with the selected seabed model within the entered time.
When the seabed is at the same depth or shallower than the current towfish depth and within the maximum time, then an alarm is generated in different displays (navigation, profile, generic and alert).
Any node can be selected for this, it doesn't have to be a deeptow towfish.
The seabed model can be the current sounding grid, an additional terrain or a user defined sounding grid.
In the Controller go to Session Setup - Monitoring.
Select 'Seabed Collision Avoidance' as Type.
(Read the How-to Monitor Dynamic Moon Pool Area for the 'Dynamic Moon Pool Area' Type.)
Select the object and the node for which you want to know if it will collide.
Set the Maximum Time (e.g. when the Maximum Time is set to 45 minutes and the expected time to collision is more than 45 minutes, no alarm will be shown).
Select the Seabed Model Source.
Three different seabed model sources can be used:
- Storage Grid (as specified in Session Setup - Storage - Sounding Grid)
- Additional Terrain (as specified in Session Setup - Planning - Additional Terrains)
- User Defined Grid (browse for an existing grid)
No additional settings need to be made in the Navigation Display.
When there is no alert, a dashed green line will be shown in the Navigation Display which represents the Maximum Time calculated based on COG and SOG.
When there will be a collision within the Maximum Time, the collision point will be shown, together with distance and time until collision.
In the Profile Display Seabed Collision should be enabled.
This can be done under View Properties - Monitors.
When there is no alert, the Profile Display will shown nothing extra.
When there will be a collision within the Maximum Time, a red line and the collision point will be shown, together with distance and time until collision.
In the Alert Display an alert should be created of the Category Computation Result and the Type Monitor.
When there is no alert, the status is OK and the Collision-Monitor alert is green.
When there will be a collision within the Maximum Time, the status will change to Alarm and the Collision-Monitor alert is red.
Under Result Data - Monitoring, all the Monitoring related items can be selected.
See the online Help file 'Monitoring' in which all the items are explained.
When there is no alert, the Collision Status is OK and shown in green.
When there will be a collision within the Maximum Time, the status will change to Alarm and is shown in red and the Collision items will have values.