Indistinct_Knots_in_NURBS_Surface

This check verifies whether the values of the angles between internal knots of a NURBS surface are in the specified range. If not, the element is considered as incorrect.

Note: A check on last modifications is available for this check.

This page discusses:

Context

NURBS and B-Spline curves are defined as knot vectors. To define NURBS and B-Spline faces, a knot vector is required for each parameter direction.

A knot vector is a sequence of real numbers used to define:

  • the number of face segments in the u and v parameter directions.
  • the continuity of the transitions between face segments.
Note: If knots coincide, they are called multiple knots, or multiple weighting of knots.

If you transfer knots to a system with larger tolerances, knots that are too close to each other can become multiple knots. Multiple knots have an impact on the number and continuity of face segments.

This can lead to undesirable changes in the continuity of the curve and in the internal continuity within the face.

Check Information

Check Details Description
Applicable to: PartFeature
Automatic Solution:
Check Parameters:
  • Max_Gap_Knots: Length type.

    Specifies the maximum distance allowed between two internal knots.

  • Min_Gap_Knots: Length type.

    Specifies the minimum distance allowed between two internal knots.