To Define Displacement Constraints
1. Click Home > Displacement. The Constraint dialog box opens.
2. Enter a descriptive name or accept the default name. Click the color swatch adjacent to Name if you want to change the color of the icon, the distribution, and the text of the constraint.
3. Select the desired constraint set from the Member of Set drop-down list. If you want to create a new constraint set, click New to display the Constraint Set Definition dialog box. Enter a name and optional description for a new constraint set.
4. If you did not select geometric entities as references before you opened the dialog box, you can now select one of the following References from the list:
Surfaces
Edges/Curves
Points
5. Select one or more references. Your selections appear in the References collector.
6. If you do not want use the current coordinate system, click World to select the WCS or click Selected to select a UCS in the Coordinate System area.
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If you are working on a 2D model, Creo Simulate uses the coordinate system you specified during the definition of the 2D model as the WCS.
7. Click one of these settings buttons for each translational and rotational degree of freedom to define how you want to constrain the geometry:
 
Translation
Rotation
Free
Fixed
Prescribed
Function (FEM mode only)
If you select a prescribed setting, enter a value in the field to the right. You can enter a value, mathematical expression, or parameter name in this field. The value should be in length units for translation constraints, and in radians for rotation constraints.
8. Click OK to complete the definition and exit the dialog box.