Marine clash checking

To clash a Marine model against the point cloud data, the XGEOM model must be added to the obstruction list. This is possible through one of the following ways:

• XG icon in the Marine Clash Display window

• Menu

Both routes are described below:

XG Icon:

1. In Marine explorer, make the XGEOM the CE.

2. Open the Marine Clash Display.

   

3. Introduce the XGEOM to the obstruction list by using the Clash against current XGEOM function in the Marine Clash Display.

Menu:

Alternatively, this can be manually assigned as follows:

4. Select Settings > Clasher > Obstruction > List.

5. Marine has <ALL> in the obstruction list by default, this needs changing to look at the XGEOM model. To remove 'All' from the Obstruction List:

   • Click to highlight All

   • Select Remove

   • Obstruction list should now read None

6. Add the point cloud representation (XCELLs) to the obstruction list, which allows standard Marine clash checks to be performed.

7. Navigate through design explorer menu to XGEOM.

8. When XGEOM is highlighted, select Add. XGEOM should appear in the Obstruction List.

   

Selecting Clash Type

The two types of clashing offered are as follows:

• Exact Clashing

• Cell based clashing

These modes can be toggled using the check box within the Marine Clash Display window. The purpose and switching of these modes is outlined below. The default mode is cell based.

Exact Clashing

When the check box is enabled as shown below, and the boxes are transparent, exact clashing is used. This compares the model against each point within the cloud.

Cell based clashing

When the check box below is as shown, and red boxes are seen, cell-based clashing is used. This may be faster than exact clashing, but gives false positives.

Selecting objects to clash against point cloud

To select objects to clash against point cloud:

9. Make a Zone or object CE in Marine explorer. This should contain objects for clash evaluation.

10. Open the Marine Clash Display Window. Utilities > Clashes.

11. In the Clash Display window, select Control > Check CE.

Viewing Clash Results

The main graphical environment displays the results of the clash evaluation:

• Elements that touch the point cloud turn red to indicate a clash.

• Points within the main 3D display window, the Clash display 3D window, and Point Cloud Manager turn red where a clash is detected.

When in cell-based clashing mode, as the clash checking is performed against a solid representation of the survey, on larger Datasets coarse XCELLS could potentially indicate clashes where none exist. Therefore, each clash should be confirmed by point volume selection.

This is not necessary when performing exact clashing.

The Clash Display now lists all clashes found between elements and XGEOM.

These can be highlighted and individually viewed in 2D and 3D windows.

See the following section for details on how to obtain BubbleView highlighted points for each clash in the list.

Marine Objects displayed in AVEVA Point Cloud Manager 3D Display

• Objects can be displayed in the Point Cloud Manager 3D environment if exact clashing is performed.

• Only those objects where clashes are displayed red.

• Objects which display green clash with an XCELL but do not clash with any points. These objects should be regarded being as a near miss, and may warrant further investigation.

  

In Point Cloud Manager, CAD Objects must be turned on to view in the rendered Marine model.

This button must be depressed for Marine objects to display in the Point Cloud Manager 3D view.

Objects can be removed from the display by toggling the CAD Objects button on the Visualisation menu, or clipped to display only within a selected volume using the Clip button.

The clear clash objects icon must be selected in the Marine Clash display after each clash, otherwise objects from previous clashes will be displayed in the Point Cloud Manager 3D view.

For further information about clash checking procedure, please refer to the AVEVA Point Cloud Manager Server section.

Clearing the clash list prior to next session

Select the icon shown below before re-clashing to remove previous clash objects.

Closing the Clash Display window removes the current highlighted clash list.