Creating a fixed coordinate system

You define a fixed coordinate system by specifying the origin and two points. The line from the origin to point 1 is the X-axis (for a rectangular coordinate system) or the R-axis (for a cylindrical or spherical coordinate system); the plane containing the origin, point 1, and point 2 is the X–Y plane (for a rectangular coordinate system) or the R–θ plane (for a cylindrical or spherical coordinate system). The coordinate system remains fixed in space regardless of the motion of the model.

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

Context:

You can either select individual nodes in the viewport or enter the X-, Y-, and Z-coordinates of the points in the prompt area. When you select nodes in the viewport, the nodal coordinates of the current plot state are used to orient the coordinate system; that is, the true coordinates of the node on the undeformed or deformed shape are used (any deformation scale factor applied to the deformed shape is ignored).

  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 Fixed system 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; or enter the X-, Y-, and Z-coordinates of the origin in the prompt area.

  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); or enter the X-, Y-, and Z-coordinates of the point in the prompt area.

  5. Select a node in the viewport to lie in the X–Y plane (for a rectangular coordinate system) or the R–θ plane (for a cylindrical or spherical coordinate system); or enter the X-, Y-, and Z-coordinates of the point in the prompt area.

    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.