Analyzing Constraints

This task shows you how to analyze the constraints of an active component.
All the items displayed in the Constraint Analysis dialog box are editable according to their respective behavior (Copy, Cut, Paste, Delete, etc).
Open the Assembly_06.CATProduct document.
  1. Select Analyze > Constraints.

 

The Constraint Analysis dialog box is displayed. The Constraints tab displays the status of the constraints of the selected component:

 
 

The Constraints tab displays the status of the constraints of the selected component:

  • Active Component displays the name of the active component.

  • Component displays the number of child components contained in the active component.

  • Not constrained displays the number of child components not constrained in the active component.

  • Status displays the status of the constraints:

    • Verified displays the number of verified constraints.

    • Impossible displays the number of impossible constraints. "Impossible" means that the geometry is not compatible with the constraint. For example, a contact constraint between two cylinders whose diameter is different is impossible.
      The yellow unresolved symbol is displayed in the specification tree on the constraint type icon:

    • Not updated displays the number of constraints to be updated. The application has integrated new specifications, which affect constraints.
      The update symbol is displayed in the specification tree on the constraint type icon:

    • Broken displays the number of broken constraints. A reference element is missing in the definition of these constraints. It may have been deleted for example. You can then reconnect this constraint (see Reconnecting Constraints).
      The yellow unresolved symbol is displayed in the specification tree on the constraint type icon:

    • Deactivated displays the number of deactivated constraints (see Deactivating or Activating Constraints).
      The deactivated symbol is displayed in the specification tree. It precedes the constraint type icon: .

    • Measure Mode displays the number of constraints in measure mode.

    • Fixed Together displays the number of fix together operations.

    • Total displays the total number of constraints of the active component.

 

In our scenario, the command displays the status of all constraints defined in AnalyzingAssembly product.

The command Analyze > Constraints displays the status of constraints defined for sub-assemblies too. What you have to do is set the combo box on top of the dialog box to the sub-assembly name of your choice.

In addition to the Constraints tab, the Broken tab and the Deactivated tab provide the name of the broken and deactivated constraints already indicated in the Broken and Deactivated fields.

The constraints are clearly identified in these tabs and you can select them. Once selected, they are highlighted both in the tree and in the geometry area.

 
 

Additional tabs may be displayed if one of these constraint status exists:

  • Impossible.

  • Not updated.

  • Measure Mode.

The tab Degrees of freedom also displays if all constraints of a given component are valid.

To redefine the colors of the different type of constraints, see Customizing Constraint Appearance.

 

This capability does not show overconstrained systems. The application detects them when performing update operations. For more information, see Inconsistent or Over-constrained Assemblies.

 
  1. Click OK to exit and delete the following constraints to perform the rest of the scenario: Coincidence.12, Parallelism.15 and Line Contact.16.

 

The document now contains only seven constraints. They all are verified.

 
  1. Select Analyze > Constraints again. The Constraints Analysis dialog box no longer contains the tabs Broken and Deactivated.

  1. Click the Degrees of freedom tab.

 
 

The application displays this tab only if all constraints are verified. The tab displays the components affected by constraints and the number of degrees of freedom remaining for each of them.

 
  1. Double-click CRIC_TOP.1.

 

The Degrees of Freedom Analysis dialog box is displayed.

 
 

One rotation as well as one translation remain possible for CRIC_TOP.1.

 
 
  1. Click Close then OK to exit.