When you choose CSYS from the
Create Datum dialog box, the Method
list displays the methods for creating a datum coordinate system.
Datum coordinates systems are used throughout
Abaqus/CAE;
for example, to define material orientations and to define connector
orientations. To help you keep track of your datum coordinate systems, you can
name the systems when you create them, and the name appears alongside their
entry in the
Model Tree.
Define a rectangular, cylindrical, or spherical coordinate system by
selecting the origin and, optionally, two additional points. In the case of a
rectangular system, the second point defines the
X-axis, and the
X–Y plane passes through
the second and third points, as shown in
Figure 1.
This is the most versatile tool for creating a datum coordinate system, and you
should use it when possible. For detailed instructions, see
Creating a datum coordinate system defined by three points.
Figure 1. Positioning a rectangular datum coordinate system by selecting the
origin and two points.
Offset from CSYS
Select a coordinate system; and provide the location of the rectangular,
cylindrical, or spherical datum coordinate system by specifying an offset, as
shown by the example involving a rectangular system in
Figure 2.
You can specify the offset by entering a value or by selecting a point. For
detailed instructions, see
Creating a datum coordinate system at an offset from another coordinate system.
Figure 2. Positioning a rectangular datum coordinate system by offsetting from
another coordinate system.
2 lines
Select two edges that define the rectangular, cylindrical, or spherical
coordinate system. In the case of a rectangular system, the first edge defines
the X-axis and the
X–Y plane passes through
the second edge, as shown in
Figure 3.
For detailed instructions, see
Creating a datum coordinate system defined by two lines.
Figure 3. Positioning a rectangular datum coordinate system by selecting two
edges.
3 points 
Offset from CSYS 
2 lines