The stamping restriction means the following: If one element is removed
from the structure, all elements positioned either behind or in front
of the element (with respect to the pull direction) are removed too.
The stamping restriction is a variant of the demold manufacturing constraint,
with the MID_PLANE parameter set to STAMP.
The following figure shows the stamping restriction for a crane hook:
Important:
The speed (step width) should not be set too high if the stamping restriction
is activated for the optimization. An unsuitable choice leads to a detaching of the supports
to the rest of the structure.