Assembly constraint errors and recovery

Inventor displays the Place/Edit Constraint error dialog box when an error occurs while you use Place Constraint or edit a constraint. This dialog box has four options for handling the error:

• Edit the Constraint: The Place Constraint dialog box displays so you can change the constraint.
• Cancel the operation: The command is canceled. If you are creating a constraint, the constraint is deleted. If you are editing a constraint, the constraint is restored to its previous state.
• Accept the constraint: The constraint displays in the browser with an error symbol. The constraint does not affect component position. It retains the selections so you can edit it later.
• Diagnose the constraint: The Constraint Conflict Analysis dialog box displays. This dialog box lists a minimal set of the components that contribute to the conflicting constraint. A conflict, which can be viewed as a minimal set of constraints that cannot coexist with each other, can then be identified within the dialog box. You can temporarily break constraints or change grounded status of components to test constraint solutions and solve the conflict. You can then delete or suppress the broken constraints.

Inventor displays the Constraint Management dialog when a conflict occurs when using Grip Snap or Assemble. This dialog displays a list of the conflicting constraints.

• Click a constraint to highlight it in the graphics window.
• Select Suppress Constraints or Delete Constraints.
• Click OK to suppress or delete the constraints or Cancel to exit without creating the constraint.

Use the Constraint Conflict Analysis dialog box to suppress or delete constraints. Also, you can change the grounded status of components to resolve constraint conflicts when using Place Constraint.

The Constraint Conflict Analysis dialog box lists only components and constraints related to the current conflict. If there are other conflicts, you are prompted to continue after resolving the current conflict.

1. Display the Constraint Conflict Analysis dialog box.
   • Select Diagnose the constraint from the Place/edit Constraint error dialog box.
   • Select Diagnose the constraint from the Suppress Constraint error dialog box.
   • Select Diagnose Inconsistent Constraint from the Treatment pane of the Design Doctor dialog box.
   • Select Diagnose from the browser context menu.
2. View conflicting constraints
   • Click the + next to a component to expand the list and display the constraints. Conflicts are displayed in bold type.
   • Select Expand All from the context menu to expand all components in the list.
   • Select the Display only conflicting constraints option to hide constraints without conflicts.
3. Set constraints to Keep or Break.
   • Click the symbol for a constraint to change that constraint.
   • Click the symbol for a component to change all constraints for that component.
   • Click the symbol at the top of the dialog box to change all constraints listed.
4. Toggle the grounded status of components.
   • Click the part/assembly icon next to a component.
   • Select a component and click the Toggle Grounded Status button.
5. Click the Check button to determine if all constraint conflicts are resolved. If the constraint is resolved, then the Solve Result changes to a green check and the Check button is disabled. You can continue to experiment and optimize the changes.
6. Select the Suppress broken constraints or Delete broken constraints option to control the effect on constraints.
7. Click OK to accept the changes, or Cancel to exit the command without changing constraints.

Use the Constraint Management dialog box to suppress or delete all conflicting constraints when using Assemble or Grip Snap.

1. Display the Constraint Management dialog box.
2. Select a constraint in the list to highlight the constrained geometry in the graphics window.
3. Select Suppress constraints or Delete constraints to control the effect on constraints.
4. Click OK to modify the constraints and complete the Assemble or Grip Snap command. Click Cancel to exit the Assemble or Grip Snap command without creating constraints.

The Design Doctor diagnoses sick constraints and identifies the components and constraints where the constraint failure occurs. The Design Doctor offers several methods to help you resolve the error.

An application option activates analysis that helps isolate components with constraints that participate in a constraint error.

1. On the ribbon, click Tools tab Options panel Application Options . On the Assembly tab, select the Enable Related Constraint Failure Analysis check box.
2. In the browser, right-click a constraint marked with either the or the symbol and select Recover to open the Design Doctor.
   • Select lists all constraint errors. Select a constraint error to highlight in the browser and graphics window. Click Next.
   • Examine provides detailed information and a suggested solution for the selected error. Click Unhighlight Problem to turn the highlighting off and on in the graphics window.

     If the problem cannot be highlighted in the graphics window (for example, if it is caused by missing geometry), Highlight changes to Continue Examination. Click Next.

   • Treat lists the options to resolve the selected error.
3. Select a treatment option.
   • Edit Constraint opens the Edit Constraint dialog box.
   • Delete Constraint deletes the constraint. If other constraints are associated with the deleted constraint, additional errors can require resolution.
   • Suppress Constraint suppresses the constraint. If other constraints are associated with the suppressed constraint, additional errors can require resolution.
   • Isolate and Edit Constraint turns off visibility of components so that you can see the affected constraint to edit. Opens the Edit Constraint dialog box.
   • Isolate Related Failed Constraints identifies all constraints and components that can cause the constraint failure. The visibility of the remaining components is turned off. Opens the Edit Constraint dialog box.
   • Diagnose the Constraint displays the Constraint Conflict Analysis dialog box. You can break conflicting constraints to determine which ones require deletion or editing.
4. For treatments that open the Edit Constraint dialog box, evaluate the constraints and geometry to determine where the error lies and adjust constraint settings as needed.

   Tip: Use Isolate Related Failed Constraints to run additional analysis to identify participants in the constraint error. Only affected components are visible.

5. For treatments that open the Constraint Conflict Analysis dialog box, you can change the status of constraints, and toggle the grounded status of components. You can test the changes to determine whether they resolve the constraint conflicts.
6. If additional treatments are needed, repeat this procedure and further evaluate the cause. Adjust constraints as necessary.

Note: If constraint errors remain, you can run the Design Doctor analysis again. When you choose the Isolate Related Failed Constraints treatment again, different components can become visible.

Use Isolate to turn off visibility of all components except the components you selected.

You can progressively isolate components by starting at a high-level assembly, and work down the browser tree, isolating to smaller sets of components.

1. In an assembly, click the components you want to isolate in the graphics window or the browser.
2. Right-click, and then select Isolate. All unselected components are set to Invisible status.

Use Undo Isolate instead of Undo to restore components to the pre-isolation state. Undo "backs up" through the last-performed operations in reverse order, including isolation. Right-click in the graphics window or the browser, and then select Undo Isolate. Component visibility is turned back on to the state before they were isolated, but unlike Undo, operations performed in the isolated state remain intact.

Undo Isolate is available only after you isolate components.

Note: Use Isolate to identify constraint errors. For example:

• When the Design Doctor displays, use Isolate as a treatment to find the constraint.
• Right-click a component in the browser and select Isolate Component. All components are made invisible except the two participants in the constraint.

Use the Assemble Constraint Management dialog box to suppress or delete conflicting constraints.

Constraint List

Lists the conflicting constraints. Select a constraint in the list to view it in the graphics window.

Suppress constraints

Suppresses the constraints you select.

Delete constraints

Deletes the constraints you select.

Use the Constraint Conflict Analysis dialog box to resolve constraint conflicts while using Place Constraint, editing a constraint, or unsuppressing a constraint.

The Constraint Conflict Analysis dialog box lists only components and constraints related to the current conflict. If there are other conflicts, you are prompted to continue after you resolve one conflict.

Specifies a method to resolve a constraint conflict.

Edit the constraint	Returns to the Place Constraint or Edit Constraint dialog box with previous settings intact. Use this method to change your selections.
Cancel the operation	If creating a constraint, returns to the Place Constraint dialog box with previous settings cleared. If editing a constraint, cancels the edit operation.
Accept the constraint	Creates the constraint or accepts the change to the existing constraint. The constraint is created and added to the browser with an icon.
Diagnose the constraint	Displays the Constraint Conflict Analysis dialog box. Use the Constraint Conflict Analysis dialog box to resolve constraint conflicts.

Specifies a method to resolve a constraint conflict when changing the suppression state of a constraint.

Edit the constraint	Displays the Edit Constraint dialog box for the selected constraint. Use this method to change the constraint.
Undo this change to suppression status	Cancel the change in suppression state. The constraint remains in its previous state.
Continue	Creates the constraint or accepts the change to the existing constraint. The constraint is created and added to the browser with an icon.
Diagnose the constraint	Displays the Constraint Conflict Analysis dialog box. Use the Constraint Conflict Analysis dialog box to resolve constraint conflicts.