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To realize an optimisation with as much freedom as possible you should disable the Keep Non-Design Spaces function for the six fixations points as well as the constraint created with them. For this to work it is important that all fixation points are fixated in one constraintYou can also create six separate constraints and deactivate all of them as well as the six Non-Design Spaces.
This way the algorithm works at its best and creates the most fitting results to the boundary conditions. With this approach it is possible to let the algorithm decide which and how many fixation points are necessary and needed for the applied boundary conditions. The reduction of fixation points almost always results in a more lightweight design by still taking into consideration the Stress Goal of the structure.
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You can see the results for the two Complexity settings and the deactivation of Keep Non-Design Spaces below.
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