Optimisation for multiple load cases

Altair Forum User

Hi guys

 

I am a relatively new user to Optistruct. I have so far been successful in creating valid models, which have given good designs for simple load cases, but I am now looking to push this forward and apply it to some real-world stuff.

 

I have a component which has to pass multiple different tests to meet its design criteria.

 

It should never have to endure them all at once and even my pre-optimisation model will not withstand them all at once. Could anyone tell me how I can get Optistruct to create some geometry which satisfies multiple loadcases individually. 

 

By way of an example, something along the lines of a cantilever beam which is optimised for a weight on its own or a lateral load on its own, but not both at the same time?

 

Any help would be good.

 

Thanks

 

Rob

Altair Forum User

Hi,

 

it depends on the type of response and objective. There are subcase independent and subcase dependent responses.

Take a look at:

 

file:///C:/Program%20Files/Altair/12.0/help/hwsolvers/hwsolvers.htm

->Altair OptiStruct > User's Guide > Design Optimization > Responses:

 

 

Subcase Independent:

• Mass and Volume
• Fraction of Mass and Fraction of Design Volume
• Center of Gravity
• Moments of Inertia
• Weighted Compliance
• Weighted Reciprocal Eigenvalue (Frequency)
• Combined Compliance Index
• Von Mises Stress in a Topology or Free-Size Optimization
• Bead Discreteness Fraction

 

Subcase Dependent:

• Static Compliance
• Static Displacement
• Static Stress of Homogeneous Material
• Static Strain of Homogeneous Material
• Static Stress of Composite Lay-up
• Static Strain of Composite Lay-up
• Static Failure in a Composite Lay-up
• Static Force
• Single Point Force at a constrained grid point
• Grid Point Force
• Temperature
• Buckling Factor
• .... and more

 

You can pick the subcases in subcase dependent responses/objectiv.

 

Regards,

Mario