Mesh CROSS SECTION Operator

Mesh Operator dialog box - CROSS SECTION operator

The Mesh CROSS SECTION operation generates a subset of polylines determined by the defined intersection of a set of parallel planes with the Mesh object. The software defines the set of planes by the start point, direction vector, step distance between the planes, and length. The software determines the number of planes by the Step distance divided into the Length plus one.

You can evaluate the Mesh CROSS SECTION operator by the profile dimension.

To apply the CROSS SECTION operation to a Mesh:

  1. From the Mesh toolbar (View | Toolbars | Mesh), click the Cross Section a Mesh button () to open the Mesh Operator dialog box. You can also click the  Insert | Mesh | Operator menu option.

  2. From the Mesh Operator dialog box, select Cross Section from the Operator list.

From the Mesh toolbar, click the 2D Section Slide Show button to display cross sections in 2D view. For details, see the "Cross Section Slide Show" section of the "Show and Hide Cross Section Polylines" topic.

The list underneath the Operator list contains these options: Vector, Axis, Curve, and 2 Points. For details on how the Curve function works, see the "Creating a Cross Section along a Curve" topic. For details on the 2 Points option, see the "Creating a Cross Section between 2 Points" topic.

The Mesh CROSS SECTION operator uses the following options:

If the Step value is greater than the Length value, the software creates only one section cut at the start point.

Use Smoothing Tol to remove small steps in the cross section and create a smoother measured polyline. This setting filters out the points within the smoothing tolerance value and then fits a polyline to the data using the Point Spacing value.

You can also define Point Spacing with the CrossSectionCopCadCrossSectionStep registry entry. For details on this registry entry, see "CrossSectionCopCadCrossSectionStep" in the PC-DMIS Settings Editor documentation.

You should set the Smoothing Tol very small so that the measured cross section does not deviate greatly from the actual data. Except for extreme situations (for example, a very large CAD model and/or a very poor density of points), you should set this parameter between a few tenths of a mm (maximum) and a few thousandths of a mm (minimum).

PC-DMIS calculates the minimum and maximum points each time you execute the measurement routine.

For example, if you select surface A after you define the start and end points, the software only creates the cross sections at B and C:

Example of a selected surface (A) limiting the cross sections to only (B) and (C)

Selected surfaces do not affect what you see when you click the View button.

When the cutting planes are visible in the Graphic Display window, it is possible to manipulate them as follows:

When you create or edit a cross section, the cutting planes appear in a transparent view as shown above.

Click Create to:

For example:

MESHSECTION3=MESH/OPER,Cross Section,TOLERANCE=0.05,WIDTH=117.715,HEIGHT=227.086,

START PT = -6.439,60.097,6.276,NORMAL = 0.9684394,-0.2221293,-0.1130655,SIZE=76

REF,MESH1,,

The black polylines represent the nominal CAD, the yellow polylines represent the measured polyline.

Finished cross sections showing five planes

Defining the Cross Section by Typing Values

Use the Mesh Operator dialog box to enter any of these values:

Defining the Cross Section by Using the Graphic Display Window

To define some of the cross section parameters, click the CAD model in the Graphic Display window to select the Start Point. A pink line appears. Click a second point on the CAD model to determine the Direction vector and the Length.

Creating a Profile Dimension from the Graphic Display Window

When you double-click a cross section label, PC-DMIS creates a new profile dimension that evaluates the selected cross section.

Exporting Mesh Cross Sections in IGES Format

Once you create the Mesh cross sections, you can export them in IGES format from the Mesh Operator dialog box.

For details on the Mesh Export operator, see "Mesh EXPORT Operator" in this documentation.

More:

2D View of Cross Sections

Creating a Cross Section along a Curve

Creating a Cross Section between 2 Points

Show and Hide Cross Section Polylines

Measuring Cross Section Distances

Viewing Cross Section Labels in Reports