CAD Import and correction in the modeler


Several formats of CAD import are directly implemented in the Flux modeler context. Different solids are directly converted in Flux objects with corresponding Flux sub-entities (points, lines, faces et volumes).

Before and after Flux 12

The evolution of CAD import using in Flux since the implementation of the modeler in Flux 12 version is presented in the table below.

Before Flux 12

(without modeler)

It was already possible to import geometry from the CAD file. This allowed the introduction of complex geometries (with curved surfaces) in the Flux project. These surfaces could not be built directly with tools in Flux.

Starting from Flux 12

(with modeler)

These imports are always possible from the modeler. As against the imports are available only in the modeler and are not available in the standard geometry context.

Imports are exactly identical with same options. The option of automatic correction has been improved. The option of assembly is always applied by default to correct possible collisions.

Starting from Flux 12.2

(with modeler)

2 user options are added on the process of CAD import :

  • Detection of collisions: If solids are in collision, the assembly of this solids is not done and the user must modify the geometry to correct this collision
  • Separation of solids: If solids are independents, each is converted in independent object

The process of CAD import simplifies automatically the “sliver” faces, which can be a problem for the mesh step.

Learn all about the imports in Flux (formats, options ...) access to different chapters of CAD import ( Import principles and Import software aspect )

Imports / Exports formats

Here is the list of CAD imports and exports available in the modeler:

Import formats Export formats
  • CATIA V4 and V5
  • STEP advanced
  • IGES advanced
  • PRoE
  • SAT
  • NX
  • DXF
  • CATIA V4 and V5
  • STEP
  • IGES
  • SAT

Detection of geometric defects

A detection of geometric defects is applied at the CAD import (if the option of automatic healing is chosen*). On each object, each ACIS entity is analyzed to detect potential defects.

Note: * a functionality of Detection of geometric defects on ACIS entities is available in the modeler context (see the block « Detect and Heal ACIS defects after CAD import». At any time, the user can check the state of his imported geometry after the import achieved.

Defects type

Here are different types of detectable and correctable defaults by the option of automatic healing:

Type Description
  • Face / Face
  • Edge / Face
  • Face / Face
  • Edge / Face
Invalid Parametering
  • Geometrical problems between contour edge and its proper face.
  • The edges are positioned on the surface.
Convexity point
  • Add point when necessary (depending on tangency variation)
Lower than
  • Small face: remove the face smaller than geometrical precision
  • Curve which close on itself
  • Surface which close on itself
Point on line
  • Vertex not on the curve à positioning of the vertex.
Position off Face
  • co-edge not on the face with repositioning of the vertex on the face.

Corrections of ACIS defaults during CAD import

To import the user can choose to automatically detect and heal defects on ACIS entities. This correction is an option and is applied by default.

This is an operation that may take some time, depending on the number of entities to be analyzed and the number of detected defaults to heal.

The user who is the guarantor of its CAD file can save time for import and deactivate the automatic correction.

Detection and Correction ACIS defects after CAD import

If the user doesn't choose the option of automatic healing, no detection and correction of geometric defects on ACIS entities were made.

After import, the user can achieve these both operations to check and heal:

  • Detect defects on ACIS entities:
    • By menu: Correction&Simplification > Detect defects on ACIS entities > New
    • By icon:
  • Heal defects on ACIS entities:
    • Par menu: Correction&Simplification > Heal defects on ACIS entities > New
    • By icon:

Warning and advice

If geometry contains defaults on ACIS entities, there is not guarantee that functionalities of Modeler will be applied correctly in any case.

If you have any doubt about the origin of the CAD file, we recommend you to import this geometry with the correction option by default.