Stress Constraints

A global stress constraint can be applied to limit the maximum stress in the model and is used when your optimization objective is to minimize mass.

Inspire analyzes the materials used in the model to determine which has the lowest yield stress, then divides by its minimum safety factor. The higher the safety factor, the more material will be added to the optimized shape to limit the overall stress in the model.

  1. On the Structures ribbon, click Run Optimization on the Optimize icon.

  2. Select Topology or Gauge for the optimization Type.
  3. Select Minimize Mass as the optimization Objective.
  4. Under Stress Constraints, the default Minimum Safety Factor is automatically calculated based on the lowest yield stress in the model, but you can enter a different Minimum Safety Factor if desired.
  5. Define additional optimization constraints and options as desired.
  6. Click Run to start the optimization.
  7. When complete, double-click the name of the run to view the results.

Minimizing Mass Subject to Stress Constraints

The motorcycle bracket pictured below was optimized by minimizing mass subject to stress constraints, defined in terms of a minimum safety factor. As the safety factor increases, more material is required to resist the loads you've applied.
Figure 1. Original Model
Figure 2. Stress Constraint with a Safety Factor of 1.2
Figure 3. Stress Constraint with a Safety Factor of 2.0