Hey,
I am just learning optistruct, 1 week in. I'm doing a topology optimization for a steel bridge competition, where the aggregate deflection needs to be less than 0.75 inches, the weight of the structure is less than 250lbs, and the sway is less than 0.25 inches. I am having trouble with error 2150. The model on hypermesh 2025.1 optistruct is just one solid. I have allocated a response id, response type=mass, and and property type = total. I have added a static displacement response with total displacement, and also a constraint with an upper bound of 0.75. I also have a mass constraint with an upper bound of 250. And my objective was to minimize the mass, total.
How can I resolve this error?
*** ERROR # 2150 ***
Invalid Volume or Mass Constraint.
The response type is the total MASS.
the upper bound value = 2.5000e+02
the total volume = 3.5386e+05
the design volume = 3.5386e+05
the total mass = 1.0014e+05
the design mass = 1.0014e+05
The design material fraction (percent) should be at least 3 times
the DOPTPRM MINDENS (default 0.01).
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Solver FAILED
OptiStruct:: Solver run finished.
