discrete size-optimization - error 1562

Rahul_P1

Hello
I permenantly get the following Error-Message while discrete size-optimization of a composite layup.

*** ERROR # 1562 ***
for element id = 30001.
Singular matrix b3 in composite homogenization precludes calculation of shear
stiffness. Make sure that composite has non-zero stiffness in all directions.
This error violates mathematical requirements and must be corrected.
This error occurs in module 'asmbdrv'.

My problem is, that I don't know where I probably made the mistake. I already compared to successful optimizations. I also don't understand, why this error occures in this step instead in a privious like free-size optimization.

best regards

Rahul_P1

Hi Lukas,

A quick thing to try for you could be to check if the composite layers all have thickness above 0,

The initial value and the lower bound values of the design variable that refers the composite layers thickness need to be higher than 0 and you could maybe increase the lower bound value and try as well.

The error is most likely due to the material definition.