Weighted links trick

[skunks]

I recently discovered an interesting trick in Creo Simulate. Normally, it is not possible to place constraints on the weighted links. When starting a static analysis, a fatal error occurs. Therefore, instead of constraints, e.g. springs to ground are required.

However, if the static analysis is integrated in a fatigue analysis, Creo forgets the pre-check and calculates without problems 🤣

[rrabe]

Ok, now you should be more specific here.... it runs but the result is GIGO or actually the is the result ok?

_ Maybe someone at PTC forgot to clear this constrain many many code ago... or most likely, they forgot to expand the pre-check...

[skunks]

Hi,
here is a simple example with the 3-point support, the static analysis is not running, but the fatigue analysis is.
Weighted connections originally come from NASTRAN, but the documentation is missing, unfortunately. The restrictions are clear so far, as the weighted connections were initially intended for the connection of point masses or point loads, without stiffening effects (possible singularities).
So my guess is that the restriction for point restraints was simply forgotten in the hierarchy.

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Guten Tag,
anbei ist ein einfaches Beispiel mit der 3-Punkte-Lagerung, die statische Analyse läuft nicht, aber die Ermüdungsanalyse schon.
Gewichtete Verbindungen kommen ursprünglich aus NASTRAN, aber die Dokumentation dazu fehlt, leider. Die Restriktionen sind soweit klar, da die gewichteten Verbindungen zunächst für die Anbindung von Punktmassen bzw. Punktlasten gedacht waren, ohne Versteifungseffekte (mögliche Singularitäten). Also ist meine Vermutung, dass die Einschränkung bei Punkt-Einspannungen in der Hierarchie einfach vergessen wurde.