Constructing an Extracted Circle

For details on extracting Auto features from a Mesh, see the "Extracting Auto Features from a Mesh" topic in the PC-DMIS Laser documentation.

For details on extracting Auto features from a Pointcloud (COP), see the "Extracting Auto Features from Pointclouds" topic in the PC-DMIS Laser documentation.

You can construct a circle that is extracted from a scanned Pointcloud (COP) or Mesh.

To do this:

  1. Ensure that your measurement routine has a Pointcloud (COP) or Mesh command.

  2. Open the Construct Circle dialog box (Insert | Feature | Constructed | Circle) or from the Constructed Feature toolbar (View | Toolbars | Constructed Features).

Construct Circle dialog box - Extracted Circle

  1. From the Method list, select the Extracted Circle option.

  2. From the Reference area, select the COP or Mesh you want to use to extract the circle from.

  3. Click on the CAD model or data to define the nominal or, in the Point section of the Feature properties area, type the nominal location in the X, Y, and Z boxes.

  4. From the Surface section of the Feature properties area, define the surface vector in the I, J, and K boxes. You can use the Material Thickness Type list and the T box below it to type in a material thickness value. For details, see the "Use Thickness" topic in this documentation.

  5. Select whether the extracted circle is an inner or outer circle type from the Inner/Outer list.

  6. Enter the diameter of the circle in the Diameter box.

PC-DMIS draws the extraction zone and centers it around the XYZ location point. This box defines the cylinder zone that PC-DMIS uses for the extracted circle. The yellow cylinder is the surface. The yellow cylinder is also the horizontal zone and the green cylinder is the vertical zone. The orange points are the candidate points that the extraction considers.

Example of an Extracted Circle showing the candidate points

  1. From the Feature Based Clipping area, define the Horizontal and Vertical values. This sets the dimensions for the green extraction zone region. Consider part variability when you define the extraction zone.

  2. If you want to filter out any points that are outside of a maximum incidence angle, from the Filters area, select the Remove points with normals outside check box and type the value in the Max incidence angle box.

  3. If you want to filter out any outlier points, from the Filters area, select the Remove outliers check box and define the Standard deviation multiple to determine which points PC-DMIS excludes as outliers.

  4. Click the Create button. Based on the parameters that you specified in the dialog box, PC-DMIS does an analysis of the candidate points, and returns (or extracts) the circle and projects it to the surface.

PC-DMIS creates the command in the Edit window:

CIR1=FEAT/CIRCLE,CARTESIAN,INNER,LEAST_SQR

THEO/<25.504,15.504,0>,<0,0,1>,8.2

ACTL/<25.504,15.504,0>,<0,0,1>,1.768

ANGLE VEC=<1,0,0>

DEPTH=0,START ANG=0,END ANG=360

DIRECTION=CCW

THEO_THICKNESS,0,

HORIZONTAL CLIPPING=1,VERTICAL CLIPPING=2,INNER HORIZONTAL CLIPPING=0

USE OUTLIER REMOVAL=YES,0,

REMOVE POINTS WITH NORMALS OUTSIDE=YES,0,

RINGBAND=ON,INNER OFFSET=0,OUTER OFFSET=0

CONSTR/CIRCLE,EXTRACTED_CIRCLE,REF=COP1