reduce step size

Rahul_P1
Rahul_P1
Altair Employee
edited October 2020 in Community Q&A

Hello,

i am running a free-size optimization and i want to reduce the step-size between the iterations. The steps optistruct takes are very large and after a few iterations the design is not feasible anymore. The optimization converges, but does not get back to a feasible design.

The objective is to reduce mass with 2 displacement constraints.

The % changes are:
Iteration 0: feasible design, no violation of responses
Iteration 1: -27,54%, infeasible, violation
Iteration 2: -27,39%
Iteration3: -6,88%

Can you explain to me, why the steps are so large and after Iteration 1 the increment is not reduced.
The online help proposes the DELTOP-option on the opticontrol panel. I have run an optimization with each a value of 0,5 (default), 0,01 and 20. How do i adjust the DELTOP-variable corretly, beacause the step size did not change.

Regards,
Alexander

Tagged:

Answers

  • Rahul_P1
    Rahul_P1
    Altair Employee
    edited November 2014

    please make sure that you have checked on the box next to the DELTOP

    506ch-Capture.JPG

  • Rahul_P1
    Rahul_P1
    Altair Employee
    edited November 2014

    This was much easier than i thought. I was sure that i checked the box.

    With 0,1 the max %-change = 10%...works very fine!

    Thanks alot!

Categories