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Input Commands | Explanation | ||
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UpSampleConfig fOptimizer_switchAddRemove=58 | Starting with iteration 58, elements are either added or removed and only every second iteration is saved. This is important for the iterations near to the end of the optimisation. | ||
iteration .level_3=20 .level_2=20 .level_1=20 .level_0=4schedule.level.0.iterationCount = 19 schedule.level.1.iterationCount = 20 schedule.level.2.iterationCount = 20 schedule.level.3.iterationCount = 5 | Specify how many iterations are calculated at which resolution level. Note that convergence should be achieved at each level. Default settings medium: 2019, 20, 20, 45 Default settings sparse: 1615, 40, 4, 45 Default settings dense: 109, 10, 40, 4 | Optimizer_stressPercentGoal .level_3=30 .level_2=40 .level_1=90 .level_0=100 | The percentage at which the target stress is reached is set5 |
schedule.level.0.eventSafetyCoefficient = 0.3 schedule.level.1.eventSafetyCoefficient = 0.4 schedule.level.2.eventSafetyCoefficient = 0.9 schedule.level.3.eventSafetyCoefficient = 1 | Scaling factor for all events' safety factor. Default settings medium: 30, 40, 90, 1000.3, 0.4, 0.9, 1 Default settings sparse: 60, 90, 0.6, 0.9, 0.95, 1001 Default settings dense: 100.1, 0.25, 500.5, 1001 |
The software uses four resolution levels from coarse to fine (level 30: coarse - level 03: fine). More or less resolution levels can be added or removed. The number behind the level indicates the number of iterations calculated on this resolution level. To remove or skip a resolution level the value can be set to 0. Moreover, the stressPercentGoal Event Safety Coefficient for each resolution level can be changed. More information about the stresses and resolution hereThis coefficient is a scaling factor for the safety factor.
To set up these additional parameters, the Input Commands (left side of the table) need to be added to the optimisation model in the Advanced User Settings Text Field. You should always make sure to give the optimisation enough iterations on one level In the picture below an example is shown. By adding these Advanced User Settings, the first (coarse) resolution level will be skipped and the optimisation starts directly at the second level. You might want to add more iterations to the remaining levels to give the optimisation the chance to reduce the material accordingly and reach a convergence in each level. Especially level 2 can use more iterations in this case.
Restart (Start Space)
With the Advanced User Settings a Restart is possible. A Start Space needs to be chosen with which the optimisation will re/start.
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This way a two-stage optimisation is also possible. An already optimised geometry can be changed (adding a strut, removing a strut) and the optimisation can be started anew. For a two-stage optimisation the resolution level and number of iterations must be chosen wisely and will need some fine tuning.
A Start Space can be marked as a Non-Design Space, thus the Start Space cannot be removed during the optimisation and will be part of the final design. Therefore, the following commands (where StartCandidate is the name of the Start Space file) need to be added as well:
geometry.StartCandidate.path = StartCandidate.stl |