Design Violations Table

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Design Violations Table

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After running an optimization, if certain design targets or constraints were not met, a warning will appear at the bottom of the Shape Explorer window.

 

shape_explorer_design_violations

 

If you click on the Design Violations button, the Design Violations table is displayed. Violations are categorized by type, including:

 

Displacement constraints
Stress constraints
Mass targets
Frequency constraints

 

Each tab in the table displays the number of violations of that type in parentheses.

 

design_violations_table

 

 

Displacement Constraints

 

Displacement constraints are used during optimization to limit the deflection of an optimized design. They are applied using the Apply Displacement Constraints tool on the Disps icon.

icon_displacement_constraint

 

After running an optimization, callouts are shown in the modeling window at each location where a displacement constraint was violated. The callout notes the amount by which the constraint was exceeded; or if there are multiple violations at the same location, this is indicated instead. Note that the callout points to where the displacement constraint was located at the time of the optimization run, even if the part has since been moved.

 

displacement_constraint_violation

 

Click on a callout to display the Design Violations table. The violations corresponding to the location of the selected callout are highlighted in the table. Similarly, selecting a displacement constraint in the table will highlight the corresponding callout.

 

design_violations_displacement

 

Bound indicates the upper or lower bound for the displacement constraint as originally defined. Achieved lists the amount of deflection that was actually achieved for the given Constraint and Load Case. Part displays the name of the part to which the displacement constraint was applied.

 

For displacement constraints with both an upper and a lower bound, Diagram shows whether the displacement constraint was violated in the positive or negative direction. For older models, a diagram may not be available, in which case it will be listed as Unknown.

 

 

 

Stress Constraints

 

Stress constraints are used when your optimization objective is to minimize mass and are defined in terms of a minimum safety factor. They are applied using the Run Optimization window, which is accessed by clicking Run Optimization Icon_Boolean_Arrow on the Optimize icon.

icon_run_optimization

 

If you apply a stress constraint and the optimization is unable to achieve the minimum safety factor, then the constraint is violated and is shown in the Design Violations table.

 

design_violations_stress

 

The type of Constraint in this case is always a safety factor, and the value for Minimum Desired is the safety factor used for the optimization that produced the violation.

 

 

 

Mass Constraints

 

Mass targets are used to specify the amount of material to keep when your optimization objective is to maximize stiffness. They are applied using the Run Optimization window, which is accessed by clicking Run Optimization Icon_Boolean_Arrow on the Optimize icon.

icon_run_optimization

 

If you apply a mass target and the optimization is unable to achieve it, then the mass constraint is violated and is shown in the Design Violations table.

 

design_violations_mass

 

Target indicates the type of mass target selected for the optimization run, while Desired displays the target value. Achieved lists the mass that was actually achieved for the given Part. If you specify mass targets for each design space, then the part names will appear under the Part column.

 

Note that the value shown in the Achieved column applies to the result as initially shown after optimization, when the topology slider in the Shape Explorer was positioned at the star. If you add or subtract material using the topology slider, the mass achieved may no longer apply.

 

 

 

Frequency Constraints

 

Frequency constraints are used to control the frequency at which an optimized part vibrates. They are applied using the Run Optimization window, which is accessed by clicking Run Optimization Icon_Boolean_Arrow on the Optimize icon.

icon_run_optimization

 

If you apply a minimum frequency constraint and the optimization is unable to achieve it for one or more of the selected modes, then the target is violated and is shown in the Design Violations table.

 

design_violations_frequency

 

Minimum Desired indicates the value specified for the frequency constraint as defined in the Run Optimization window. Achieved lists the frequency that was actually achieved for the given Mode.