Creating Constraints via a Dialog Box  

This task shows you how to set geometrical constraints via a dialog box. 
 
Create two lines.
 
  Make sure the Show Constraints is active in the Visualization toolbar.

For the purpose of this scenario, also make sure that the Create Detected Constraints is active in the Tools toolbar: this option creates lasting constraints (if you do not activate this icon, the constraints you create are temporary: the geometry is only temporarily constrained, which means that it can subsequently be moved without being constrained.).

 
1. Select the geometrical elements to be constrained to each other. For the purpose of our scenario, select the two lines you created.
 
  2. Click Constraints Defined in Dialog Box   from the Geometry Modification toolbar.
 

 
  The Constraint Definition dialog box appears. The options corresponding to the various types of constraints you can create for the selected elements are active.

3. Select the Parallelism option to specify that the selected lines should be parallel.

 

 
You can preview the result.
 
  4. At this time, you can still select another option from the dialog box if you decide to apply another type of constraint. For the purpose of the scenario, simply click OK to validate. Both lines are now constrained as parallel to each other.

5. Modify the position of one of the lines, by moving one of its end points, for example.
  As you can see, the lines are constrained so as to remain parallel to each other, whatever the new position and/or length you assign to one of them.

 
  • It is impossible to create constraints between 2D and generated elements via the Constraint Definition dialog box.  In the Constraint Definition dialog box, you can only create constraints between similar elements. In other words, you can create constraints either between 2D elements, or between generated elements, but not between a mix of these. 
  • Even though you set a constraint relation between two elements, constraints are not necessarily visualized. If you cannot visualize constraints even though the Show Constraints option is active in the Visualization toolbar, go to Tools > Options > Mechanical Design > Drafting > Geometry tab and select Display Constraints. (You can also modify the constraint color and/or width.)