Constraint assignment

The goal of this guide is to go over each of the constraints available in Pareto and what they do. It will cover all constraints but Cyclic Symmetry. Click here to review Cyclic Symmetry.

Setup

For this section of the guide, we will be using the SwingArm.SLDPRT file from the ParetoWorks Examples directory on your desktop. Activate ParetoWorks and apply the following to the loaded model:

  • Assign the model material to AlloySteel

  • Add a fixed condition to the interior surface of the hole on the short side of the model. (Figure 1)

  • Add a force of 1500N in the negative Y direction to the interior surface of the other hole in the model. (Figure 2)

Finally, run static FEA on the model.

Figure 1 — Assigning a fixed condition

Figure 2 — Assigning a force

Manufacturing Constriants

Extrude

The Extrude constraint is used when optimizing a model that will be manufactured using an extrusion process. The Extrude and Drawdirection constraints may not be active at the same time. The options available for extrude are:

  • X Direction

  • Y Direction

  • Z Direction

The value will tell Pareto which axis the model will be extruded from and optimize accordingly. Figure 3 shows the Swing Arm model optimized to be extruded along the Z axis.

Figure 3 — SwingArm optimized with an extrude constraint

Draw Direction

The Drawdirection constraint specifies the direction in which the model could be cast in. Drawdirection is not available while Extrude is active. The available options for draw direction are x, y, and z. Figure 4 shows an example of the swing arm optimized with the draw direction constraint.

Figure 4 —SwingArm optimized with a Drawdirection constraint

MinFeature

The minimum feature constraint is useful when it is needed to specify the minimum size of a feature generated by Pareto. This feature size is relative to the element length. This option takes positive whole numbers as an input. Figure 5 shows the Swing Arm model optimized with a MinFeature value of 3.

Figure 5 — SwingArm Optimized with MinFeature set to 3

Max Displacement

The max displacement constraint tells Pareto to optimize in a fashion that does not allow the loads to bend or distort the part more than an allowed value. This value is in the units selected when initializing the plug-in. Accepted values are positive decimal numbers.

Stress safety factor

The Stress Safety Factor constraint tells Pareto to stop optimizing a part when the optimized part’s safety factor approaches this value. The valid range for this option are decimal values between 1 and 100.

Minimum frequency

The Minimum Frequency constraint tells Pareto to avoid testing an optimized part below a particular frequency. The valid range for this option are decimal values between 0 and 1,000,000


keep fixed faces

The final constraint, Keep Fixed Faces tells Pareto to avoid doing any optimization to faces that have a fixed design condition.