Checking Connections Between Surfaces  

Checking Connection Between a Surfaces' Border

1. Click Connect Checker Analysis in the Shape Analysis toolbar.

2. Select both surfaces to be analyzed.

3. Click Surface-Surface Connection   and select the Boundary option.

The Connect Checker dialog box is displayed.

Click the Internal edges button to turn it on, if you want to analyze the internal connections. By default, the icon is deactivated.

Two cases are available:

• Surfaces are isolated. Only geometrical connections are checked, that is all pairs of neighboring surface edges within the tolerance given by the Maximum gap. Depending on the Maximum gap value, interference connections may be detected, for instance when surfaces have a size smaller the Maximum gap. In this case, you must decrease the Maximum gap value or join the surfaces to be analyzed (see next point)

• Surfaces are joined (using the Join command for instance) and the Internal edges option is checked. Topological connections, that is all edges shared by two topological surfaces are checked first. Then, the corresponding pairs of surface edges are checked to detect any geometrical connections within the tolerance given by the Maximum gap.

4. Choose the analysis type to be performed: Distance (G0), Tangent (G1), Curvature (G2) and Curvature-Tangency (G3).

5. Set the Maximum gap for the connection analysis. The Connect Checker measures the gap of every connection between each of the borders of each of the geometrical elements, irrespective of the size of the elements.

• If the value of the gap is less than Maximum Gap, the connection is analyzed.

• If the value of the gap is outside of this limit, the connection is not analyzed.

6. Select any of the two color scale mode:

   • Limited Color Scale : In this mode, a specific color and a specific threshold are associated to the continuity type.

• Full Color Scale : In this mode, only one type of continuity is performed, therefore a color scale allows the user to work with range of values.

7. The Auto Min Max button enables to automatically update the minimum and maximum values (and consequently all values between) each time they are modified.

• You can right-click on a color in the color scale to display the contextual menu:
  

  • Edit: it allows you to modify the values in the color range to highlight specific areas of the selected surface. The Color dialog box is displayed allowing the user to modify the color range.
    

  • Unfreeze: it allows you to perform a linear interpolation between non defined colors. The unfreezed values are no longer highlighted in green.

  • No Color: it can be used to simplify the analysis, because it limits the number of displayed colors in the color scale. In this case, the selected color is hidden, and the section of the analysis on which that color was applied takes on the neighboring color.

• You can also right-click on the value to display the contextual menu:
  

  • Edit: it allows you to modify the edition values. The Value Edition dialog box is displayed: enter a new value (negative values are allowed) to redefine the color scale, or use the slider to position the distance value within the allowed range, and click OK. The value is then frozen, and displayed in a green rectangle.
    

  • Use Max/Use Min : it allows you to evenly distribute the color/value interpolation between the current limit values, on the top/bottom values respectively, rather than keeping it within default values that may not correspond to the scale of the geometry being analyzed. Therefore, these limit values are set at a given time, and when the geometry is modified after setting them, these limit values are not dynamically updated.
    The Use Max contextual item is only possible if the maximum value is higher or equal to the medium value. If not, you first need to unfreeze the medium value. Only the linear interpolation is allowed, meaning that between two set (or frozen) colors/values, the distribution is done progressively and evenly.
    

    Important: To access the Edit and the Unfreeze contextual menu for a color and a value on the color scale, ensure that the Auto Min Max check box is cleared.

The color scale settings (colors and values) are saved when exiting the command, meaning the same values will be set next time you edit a given connection analysis capability. However, new settings are available with each new connection analysis.

8. Under the Display filter area, use the spinners to define the deviation tolerance limits.
   
   
   You can click button to automatically fill the minimum and maximum values.

9. Check the analysis results on the geometry.

Here we are analyzing the distance between the surfaces. Each color section indicates on the geometry the distance between the surfaces.

There may be a tangency discontinuity while a curvature continuity exists. This may appear for instance in the case of two non tangent planar surfaces.

From the Connect Checker dialog box, you can choose a number of visualization and computation options:

• the comb : that is the spikes corresponding to the distance in each point

• the envelope : that is the curve connecting all spikes together

• Information and : that is the minimum and maximum values displayed in the 3D geometry

Finally, the scaling option lets you define the visualization of the comb. In automatic mode the comb size is zoom-independent and always visible on the screen, otherwise you can define a coefficient multiplying the comb exact value.

9. Check the Information buttons.

Two texts are displayed on the geometry localizing the minimum and maximum values of the analysis as given in the Connect Checker dialog box.

You can also choose the discretization, that is the numbers of spikes in the comb (check the Comb option to see the difference).
The number of spikes corresponds to the number of points used for the computation:

• Light : 5 spikes are displayed.
  This mode enables to obtain consistent results with the visualization of sharp edges.
  An edge is considered as sharp if its tangency deviation is higher than 0.5 degree. To only detect tangency deviations on sharp edges, specify a deviation of 0.5 degree minimum.
  To visualize sharp edges, make sure the View > Render Style > Shading with Edges and Hidden Edges option is checked.

• Coarse : 15 spikes are displayed

• Medium : 30 spikes are displayed

• Fine : 45 spikes are displayed

The number of selected elements and the number of detected connections are displayed at the bottom of the dialog box.

10. Click the Quick display mode button to obtain a simplified analysis taking into account tolerances.

The comb is no longer displayed.

The Maximum gap and information are retained from the full analysis. The maximum deviation value is also displayed on the geometry.

You can use the check button to select one or several analyses. As a consequence, the colorful area displaying the deviation tolerance between the surfaces shows the continuity whose value is the lowest.

In the case you select several types of continuity, the Information buttons are grayed out.

• You can check the Overlap Defect button to highlight where, on the common boundary, the two surfaces overlap. In this case the other analysis types are deactivated.

• You can check the Information buttons to display the minimum and maximum values in the 3D geometry, or uncheck it to hide the values.

11. Under the Display filter area, use the spinners to define the deviation tolerance limits.
    
    
    You can click button to automatically fill the minimum and maximum values. You can specify a color for each analysis type by clicking on the color icon available before each row.

12. Click OK to create the analysis.

The analysis (identified as Connect Checker Analysis.x) is added to the specification tree.

This allows the automatic update of the analysis when you modify any of the surfaces, using the control points for example.
If you do not wish to create the analysis, simply click Cancel.

• If you wish to edit the Connection Analysis, simply double-click it from the specification tree.

• If you no longer need the Connection Analysis, right-click Connect Checker Analysis in the specification tree, and choose Delete.

In the case of a curvature analysis type, the result is not guaranteed if a tangency discontinuity exists.

• You can analyze internal edges of a surface element, such as a Join for example, by selecting only one of the initial elements:
  

• You can create an analysis on an entire geometrical set simply by selecting it in the specification tree.

Checking Connections Between a Surface's Border and Its Projection on a Surface

1. Click Connect Checker Analysis .
2. Select both surfaces to be analyzed.
3. Click Surface-Surface Connection in the dialog box and the Projection option in the Connect Checker analysis dashboard.

The Connect Checker dialog box is displayed.

Check the Internal edges option if you want to analyze the internal connections. By default, the check box is unchecked.

Two cases are available:

• Surfaces are isolated. Only geometrical connections are checked, that is all pairs of neighboring surface edges within the tolerance given by the Maximum gap. Depending on the Maximum gap value, interference connections may be detected, for instance when surfaces have a size smaller the Maximum gap. In this case, you must decrease the Maximum gap value or join the surfaces to be analyzed (see next point)

• Surfaces are joined (using the Join command for instance) and the Internal edges option is checked. Topological connections, that is all edges shared by two topological surfaces are checked first. Then, the corresponding pairs of surface edges are checked to detect any geometrical connections within the tolerance given by the Maximum gap.

4. Choose the analysis type to be performed: Distance (G0), Tangent (G1), Curvature (G2) and Curvature-Tangency (G3).
    
5. Set the Maximum gap for the connection analysis. The Connect Checker measures the gap of every connection between each of the borders of each of the geometrical elements, irrespective of the size of the elements.
• If the value of the gap is less than Maximum Gap, the connection is analyzed.
• If the value of the gap is outside of this limit, the connection is not analyzed.
  There may be instances (such as very small elements, or very large Maximum Gap) where the system finds connections which are unexpected. In these instances, adjust the value of Maximum Gap until the unexpected connections are eliminated.
   
6. Check the analysis results on the geometry. The subsequent sections show the result of connecting a curve and a surface with a combination between G0, G1 or G2 and Projection.

G0 Continuity

G1 Continuity

G2 Continuity

G3 Continuity