Setting target percentages for the design space, before/after

Altair Forum User

I see that you can select different target percentages for the design space before an optimisation run begins.

I also see that you can select different target percentages for the design space after the run is completed.

Does selecting the percentage before or after the topology optimisation change the results significantly?

What I am asking is, does it matter when I select the design space target percentage?

Rahul_P1

It is always important to specify the design space % before the optimization run, what we specify with the topology slider after the run is not a design space target, it is to analyse the quality of your results and is used as a basis to decide what is your design targets, as help says - 

 

Use the Topology slider on the Shape Explorer to analyze the quality of your results. If the topology of your shape doesn’t change much when you move the slider, this means you’ve arrived at a good solution and may even be able to make your design targets a bit more aggressive. If the topology changes significantly when you move the slider, you should consider relaxing your design targets and rerunning optimization until the topology remains consistent when the slider is moved.

The optimal result is the point on the slider at which all of the load and support locations are just connected. When your optimization objective is to maximize stiffness, the optimal shape is generally found near the center of the slider marked by the star. When your optimization objective is to minimize mass, the optimal shape is often found to the far right of the slider.