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Differential Stiffening Run with DMIG entries


After running some test cases, it looks pretty clear that if your model includes
DMIG entries for hardware, that hardware is not included in either the Grid Point
weight generator summary OR the modal solution when attempting a differential stiffening
(STATSUB routine) solution. Run a simple cantilevered beam model, then replace
the second half of it with a DMIG representation of the mass and stiffness. Each
model will give the exact same answers for a normal modes solution. But now if
you apply a distributed load to only the first physical element and set that load
to 0.0 lb/in you should once again get exactly the same results. For the model
with only CBEAM elements you will. However, for the model where half is a DMIG,
you will get the exact results for only a cantilver beam of the half-length (the
length still represented by CBEAMs). Somewhere in the STATSUB routine NX is losing
the DMIG entries.
Anyone else seen this?