During my civil engineering studies, I've come across the notion of a "Polplan", a method for determining the possible infinitesimally flexible configuration of a statically indeterminate truss or more general for any multi-beam structure.
In the figure provided you see most of the parts that make up a Polplan: There are "main poles" (Hauptpole), which denote the center of a infinitesimal rotation of the corresponding rigid body. You can also see the "secondary poles" (Nebenpole), which denote the locations where any two rigid bodies exibit the same infinitesimal displacement. In orange you can see the infinitesimal displaced figure.
There are certain rules (which can be found on the German Wikipedia here), which allow to deduce the "Polplan" for any statically underdeterminant structure.
Is there an english term for this procedure?
EDIT: Not the original question, only the context:
My goal with this question is to find out whether there is a nice mathematical framework with which one can deduce the polplan without solving the constraint satisfaction problem given by the rules. The english term would allow me to find english ressources on it.
pole plan
in the translation $\endgroup$