Structural analysis and manipulation

Hi,

I am working on a project at the moment where i pixelate objects.

Currently I can only create the objects in a single size of box, what i would like to be able to do is analyse the structural loads of the object and identify the areas under most stress. I have been told that this is in regards to millipede perhaps but i cant seem to figure it out. I want to try and link the box size to the amount of stress so that the larger the stress the larger the box. Can anybody help?