Adjusting nodal coordinates

Nodal adjustment is used for:

  • adjusting user-specified nodal coordinates so that the nodes lie on a given surface; and

  • specifying the direction along which the nodes are moved.

The following topics are discussed:

Related Topics
In Other Guides
*ADJUST
Defining adjust points constraints

ProductsAbaqus/StandardAbaqus/ExplicitAbaqus/CAE

Adjusting nodal coordinates

In general, user-specified nodal coordinates are not modified during input file processing. However, there are some situations where mesh coordinates are known only in a generic way and it is inconvenient to determine their coordinates for their actual usage. For example, when using fasteners the specified reference node should be positioned at its projection point on the associated surface. Since that location may be known only approximately, you can use nodal adjustment to move the reference node to that location automatically. For typical usage of the nodal adjustment feature, refer to About assembled fasteners.

When using this feature, the nodes are adjusted to lie on the specified surface without regard for shell thickness or shell offsets. Therefore, it is not advisable to use this feature as a way of correcting initial overclosures for contact or for tie constraints. In addition, care should be taken when choosing the nodes to be adjusted because the feature does not respect any constraints relating the relative position of the adjusted node with other nodes (e.g., rigid body definitions).

Input File Usage

Use the following option to identify the nodes to be moved and the surface onto which the nodes are to be moved:

ADJUST, NODE SET=name, SURFACE=name

Abaqus/CAE Usage

Use the following option to move the control point of a coupling constraint onto the coupling surface:

Interaction module: ConstraintCreate: Coupling; Adjust control point to lie on surface

Use the following option to move any point or points onto any surface:

Interaction module: ConstraintCreate: Adjust points

Specifying the nodal adjustment direction

A node can be moved to the surface using a normal adjustment or a directed adjustment. By default, the node is adjusted to the closest point on the specified surface along the normal to the surface. You can specify an orientation to move the node to the surface along a given direction rather than along the normal to the surface. The vector along the local Z-direction from the orientation definition is used to move the node to the surface (see Orientations). If no projection can be found, the nodal coordinates are left unmodified.

Input File Usage

ADJUST, ORIENTATION=name

Abaqus/CAE Usage

The orientation projection option is not supported in Abaqus/CAE.