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either no force or displacement is applied → no stresses are available for the stress optimization to prevent the material from being reduced
or the force applied is too small
or the additional fixation is not needed for the defined boundary conditions and optimization constraints
If you are using the symmetry function with the whole model, the optimizer won't use the symmetrical Nondesign spaces and will notify you thereof - don’t worry everything is just as it is supposed to be
Steps to prevent this behaviour:
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