NURBS Surface-curve Interaction

Analyzing NURBS Curves and Surfaces

The Analysis tool provides proximity, intersection, and curvature information for NURBS curves and surfaces.

Two modes are available.

 

Mode	Description
Proximity	Determines the minimum distance between NURBS curves/surfaces and 3D loci, or the intersection between NURBS curves/surfaces
Interrogation	Interactively determines the curvature of NURBS curves and surfaces and displays curvature parameters

Determining NURBS Curve and Surface Proximity

In Proximity mode, the Analysis tool places a 3D locus at the minimum distance or intersection between two NURBS curves, a NURBS curve and NURBS surface, and a 3D locus and NURBS curve or surface. The tool places a NURBS curve at the intersection of two NURBS surfaces.

 

To analyze NURBS proximity or intersection:

1.	Click the Analysis tool from the 3D Modeling tool set, and then select Proximity from the Tool bar.

2.	Click on a NURBS curve, NURBS surface, or 3D locus, and then click on another NURBS curve or surface.

A red 3D locus is placed on each NURBS curve at the closest minimum distance or intersecting points between the two items, or a NURBS curve is placed at the intersection of two NURBS surfaces.

Determining NURBS Curvature

The Analysis tool, in Interrogation mode, provides curvature parameters for NURBS curves and NURBS surfaces, and interactively displays curvature circles.

Analyzing NURBS Curves

 

To determine the curvature of a NURBS curve:

1.	Click the Analysis tool from the 3D Modeling tool set, and then select Interrogation from the Tool bar.

2.	Click on the NURBS curve of interest and move the cursor along the curve to display the curvature circle at the cursor position.

3.	Click the curve to obtain curve properties at a specific location along the curve. The Curve Properties dialog box opens, displaying curvature parameters for that location.

4.	Select Locus at center of curvature and click OK to place a 3D locus and curvature circle, as well as a 3D locus at the center of curvature of that location.

Analyzing NURBS Surfaces

 

To determine the curvature of a NURBS surface:

1.	Click the Analysis tool from the 3D Modeling tool set, and then select Interrogation from the Tool bar.

2.	Click on the NURBS surface of interest and move the cursor along the surface to display the curvature circles at the cursor position.

3.	To obtain surface properties at a specific location along the surface, click. The Surface Properties dialog box opens, displaying curvature parameters for that location.

4.	Select Loci at centers of curvature and click OK to place a 3D locus at the point on the surface where the curvature parameters are being calculated, and a curvature circle with a 3D locus at the center of the curvature circle for each curve at that location.