Creating a coordinate system following three nodes

You can define a coordinate system that is attached to nodes on your model by specifying three nodes. The line from node 1 (the origin) to node 2 is the X-axis (for a rectangular coordinate system) or the R-axis (for a cylindrical or spherical coordinate system); the plane containing the three nodes is the X–Y plane (for a rectangular coordinate system) or the Rθ plane (for a cylindrical or spherical coordinate system). The motion of the coordinate system is defined by the translational motion of the three nodes.

Related Topics
Saving a coordinate system to an output database file
Controlling the display of model entities

Context:

The visual display of coordinate systems that follow nodes on your model is updated to reflect any deformation scale factors applied; however, result transformations based on these coordinate systems use the actual, not the scaled, deformations.

  1. From the main menu bar, select ToolsCoordinate SystemCreate.

    The Create Coordinate System dialog box appears.

    Tip: You can also create a coordinate system by using the tool in the toolbox or the Session Coordinate Systems container in the Results Tree for the current output database.

  2. In the Create Coordinate System dialog box:

    1. Accept the default name for the coordinate system, or enter the name of your choice in the text field.
    2. Toggle on System following 3 nodes to specify the motion of the coordinate system.
    3. Select one of the following as the coordinate system type:

      • Rectangular: The X-, Y-, and Z-axes are interpreted as the 1-, 2-, and 3-axes, respectively.

      • Cylindrical: The R-, θ-, and Z-axes are interpreted as the 1-, 2-, and 3-axes, respectively.

      • Spherical: The R-, θ-, and ϕ-axes are interpreted as the 1-, 2-, and 3-axes, respectively.

    4. Click Continue.

    Abaqus/CAE displays prompts in the prompt area to help you define the coordinate system axes.

  3. Select a node in the viewport to be the origin.

  4. Select a node in the viewport to lie on the X-axis (for a rectangular coordinate system) or the R-axis (for a cylindrical or spherical coordinate system).

  5. Select a node in the viewport to lie in the X–Y plane (for a rectangular coordinate system) or the Rθ plane (for a cylindrical or spherical coordinate system).

    The coordinate system appears in the viewport, in the list in the Coordinate System Manager, and under the Session Coordinate Systems container in the Results Tree for the current output database. Abaqus saves user-defined coordinate systems only until the output database is closed unless you save them to the output database file. You cannot edit a coordinate system once it has been created; you can rename or delete coordinate systems that have not been saved to the output database.