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  1. fredriki

    RESVEC Modal Contribution

    Thank you Rahul, I have actually tried that but it gets overwritten since I use TLOAD1.
  2. fredriki

    RESVEC Modal Contribution

    Hello everyone! I'm performing an analysis where I find the modal contribution (SDISP) in a linear modal transient analysis. My problem is that I have 18 RESVECS that introduce weird RESVEC modes that optistruct states have the most contribution. Can I get rid of these RESVECS from the calculations or can I use another approach? Regards /Fredrik
  3. fredriki

    Question about split die

    Hello, when I perform optimization using a split die, do I need to specify where the dies are split? To be more specific, are the dies split at the anchor node?
  4. Hello! I am writing a report and I want to explain the optimization method I have been using. I have some information on Dual Optimizer based on separate convex approximation but I am having a hard time finding how optistruct calculates the next step in the gradient method. I have searched the documentation but I have not really found an answer.
  5. fredriki

    Optimization parameters in MMO

    I have an answer now from running two inputs, the master input does not seem to transfer to the slave inputs.
  6. Hello! I am running an MMO where I define the optimization parameters ( DOPTPRM ) in the master input file. If I want the same parameters to apply in the different slave input files, do I need to define them there as well or will they automatically follow from the master file?
  7. fredriki

    Problem with MPCs in optimization

    Ok, I will try, thank you!
  8. Hello! When I run an optimization problem with Minimizing weighted compliance subject to volume fraction constraints I get this message and then it runs. When I change objective to minimize mass subject to stress constraints I get this message and then it crashes after iteration 0. The last output message is: "OptiStruct error termination report printed to file "5150_More_DVs_MM.stat"." I am trying to find the reason for termination in this file but I cannot see what went wrong. Could someone please help me with this? I have attached the stat file that the solver refers to. 5150_More_DVs_MM.stat
  9. fredriki

    MMO, Pattern Repitition, Master and Slave

    Ok, I am trying now to keep Master IDs and changing slave IDs, seems to work but I have a follow up question. If I define different slave IDs they will all still follow the same Master ID in 3 of my configurations. But in my other 3 configurations, the DV that is master in the 3 previous configurations is not included. My thought is that I use the same Master ID as I did in the first 3 configurations, but change the coordinate system to the location of where I want the master to be oriented, and use unique slave IDs. This way I should be able to account for the same Master ID in 6 configurations and the rest of the slaves will follow in each configuration. This should work, right?
  10. fredriki

    MMO, Pattern Repitition, Master and Slave

    I got this message now when I tried to run the file. Error # 6476 "DTPL card 2 exists in multiple models with SLAVE data. Design domains linked through multi-model optimization cannot have SLAVE data." Any ideas?
  11. fredriki

    Problem with ACCEL1 and ACCEL2

    Thank you very much! I attached a part of the model file to your file transfer.
  12. Hello! I am setting up an MMO with 6 configurations. In the first 3 of these there are 3 design variables that have no intermediate relations. In the other 3 configurations there are 4 design variables where the 3rd is constrained to repeat the pattern of the 4th. But the 3rd that is constrained to repeat the pattern of the 4th is also in the 3 first configurations. My question is: Can I define the 3rd DV to be a repeated pattern of the 4th in 3 of the configurations and at the same time define it as a master pattern with + COORD in the three other configurations?
  13. fredriki

    Problem with ACCEL1 and ACCEL2

    The node being accelerated is a CONM2 element with inertia properties defined in the elements card, it is attached to RBE3 elements that are connected to a floor of shell elements. Due to customer requirements, I am not allowed to share the model file, I can try to share parts of it to make it easier for you to help me.
  14. Hello! I am having problems with accel1 and accel2 cards. When I apply the loads they exist in the input file but when I run the analysis and look at the results, 3 of 9 accelerations are not applied. The 3 cases that are not working are all applied on the same node. Any ideas? The marked cases are the ones where the accelerations are not applied. The two first cases are not accelerations.