Dredging - Intrusion
Because of safety issues it is possible that a vessel is allowed to enter a certain area but is not allowed to have the dredge tool close to the seabed because of objects - for example live gas pipelines - on the seabed.
In this case it is possible to use the “Intrusion Detection” option.
First set a Warning corridor around the avoidance zone, then define the Error corridor within this Warning corridor.
Every calculation cycle QINSy will check whether the dredge head(s) is/are located in the proximity of the predefined avoidance areas.
When a dredge head enters the avoidance area then QINSy can signal the dredge computer to hoist the ladder or suction pipe so that the objects don't get damaged.
In the Generic Display and Alert Display the status of the so-called emergency hoist can be visualized.
The avoidance areas are stored in a LineData folder, in a line database layer as poly lines consisting of two or more points: Easting, Northing and Height in local survey datum.
An entire area (2D) can be created by defining a closed poly line; the last point of the poly line should be identical to the first.
Note that such an area will always be checked in 2D mode only, ignoring the dredge head height.
Any non-closed poly line can be handled in 3D mode.
It is also possible to use the hull of an object present in the template database as an avoidance area.
For instance to prevent a backhoe from hitting a barge.
Settings | |
|---|---|
Pro File | Check this box to receive avoidance objects from a *.pro file. Use the browse button to select the correct *.pro file which contains the avoidance information. |
Layer | Select the correct layer containing the avoidance poly lines. |
Horizontal Clearance Warning | If the horizontal distance between the avoidance object and the dredgehead is smaller than this distance, the Intrusion Detection Warning Alert is raised. |
Horizontal Clearance Error | If the horizontal distance between the avoidance object and the dredgehead is smaller than this distance, the Intrusion Detection Error (e.g. Emergency Hoist) Alert is raised. |
Vertical Clearance | Minimal vertical distance between dredge head and avoidance poly line. |
Height Mode | Choose between: |
| Dynamic object | Check this box to use the hull of an object defined in the Database Setup as the avoidance object. Use the drop down menu to select the desired object. |
| Save to Pro File | Check this box if you wish to save the warning and error area polygon to a *.pro file. This way the areas can be visualized in for example the Navigation Display. Select which file to store the data in using the browse button. |
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