Constraints create non-numerical relationships that control the geometry of a sketch. As you edit a sketch, Abaqus/CAE applies solution methods to avoid violating the constraints. Several methods are available for use either when entities are dragged or when they are edited using other sketcher tools.
Note: The constraint solution method does not prevent sketch modification tools from overriding applied constraints. For example, you can use the Translate tool to move a line that has a Fixed constraint.
In addition, you can use the Show constraints option to hide the constraints and reduce clutter in the sketch and the Add constraints during entity creation option to add the constraints that are implied during sketching. You can select the linear and angular tolerance and the types of constraints that can be created automatically with the Auto-Constrain tool.
Constraint customization options apply to the entire Abaqus/CAE session. They are not saved with individual sketches or with the current model.
To customize the use of constraints in the Sketcher:
From the bottom of the Sketcher toolbox, select the Sketcher customization tool 
.
The Sketcher Options dialog box appears.
Click on the Constraints tab.
Select the desired constraint solution methods for use while dragging sketch entities or during other types of editing. The following selections are available:
Standard
This is the default solution method for editing. Abaqus/CAE moves or modifies the geometry by the minimum amount to satisfy the constraints and dimensions. Abaqus/CAE also attempts to maintain a rigid body appearance of the uninvolved geometries during the move.
Weighted
Abaqus/CAE moves or modifies the geometry by the minimum amount to satisfy the constraints and dimensions. The rigid body appearance of the uninvolved geometries are not considered during the move.
Minimum move
This is the default solution method for dragging. Abaqus/CAE moves the minimum number of entities to satisfy the constraints.
Relaxation
Abaqus/CAE moves the geometry using a numerical solution technique to minimize the sum of the squares of the movements. This solution method results in more geometries being moved compared to other methods.
If desired, toggle Show constraints.
When Show constraints is on, Abaqus/CAE displays constraint symbols in the sketch.
If desired, toggle Add constraints during entity creation.
When Add constraints during entity creation is on, Abaqus/CAE adds the constraints that are implied during sketching. For example, if you are sketching a line for which the preselection symbol indicates Abaqus/CAE will apply a horizontal constraint and Add constraints during entity creation is on, the horizontal constraint is added to the line.
In the lower portion of the page, toggle the constraint types available for use with the Auto-Constrain tool. (For more information, see “Automatically constraining a sketch,” Section 20.12.1.)
After you have chosen the desired customization options, click OK to apply your changes and to close the Sketcher Options dialog box.
