About Concept Curves

This section deals with basic concepts you should know before beginning with creating concept curves. You need concept curves to create other Concept Structure Engineering geometry, concept surfaces for example.

See Also
Creating a Concept Line
Modifying a Concept Curve

A concept curve is created if you select two points.

There are three different types of curves:

Curve or guide curve
You can directly create this type of curves. They are not part of an object like a concept surface or a joint, and are stored inside the modules.
Link curve and user-defined link curve
A link curve directly belongs to a concept surface or a joint. These curves are automatically generated in most cases. You can also create link curves that are then called user-defined link curves.
Section domain
This type describes curves that belong to a section. These curves are automatically generated. The shape of the section domain derives from the related curves in the sketch.

A concept curve can have a curvature by adding tangents to it.

A guide curve or a link curve can have two tangents, a tangent at the start point and one at the end point. When you create a curve, it does not have any tangents. That means that there is no user specification for the tangential direction of the curve at the start and the end point.

It is impossible to add tangents to section domains.

Tangents for guide curves and user-defined link curves

If the curve has no tangent, it is a straight line.

If the curve has only a tangent at one side, it follows the tangent definition on this side. The tangential direction at the other curve side is automatically optimized.

If the curve has two tangents, it follows the tangent definition on both sides.

Tangents for link curves that are automatically generated

If the link curve has no tangent, the tangent direction at the ends derives from the tangent direction of the guide curve of the concept surface or joint at the corresponding position.

If the link curve has only a tangent at one side, it follows the tangent definition on this side. The tangential direction at the other side derives from the tangent direction of the guide curve of the concept surface or joint at the corresponding position.

If the link curve has two tangents, it follows the tangent definition on both sides.

The tangent object stores a direction in the local axis system and a tension that is a weight factor to control the tangent's length.