CATIA V5 user-defined connections start-middle-end options 1

[sb009441]

My question is regarding the definition of user-defined constraints in the context of a Catia V5(r14) FEM analysis. The dialog box for user-defined constraints asks you to define start-middle-end. What do start, middle and end exactly represent? Also, is there an easy way to explain all the "middle" options (e.g. rigid-spring, rigid-spring-rigid, spring-rigid...what is the difference between these?). I have looked through the CATIA help files and google but have found nothing really useful...any help is appreciated!!

Thanks in advance for you help,

Simon

 

[PeterGuy]

My understanding of it is as follows

Start is the connection to the first mesh and is a kinematic element (transmits displacement)
End is the connection to the second mesh and is a kinematic element (transmits displacement)
and middle is the behaviour of the link between the two kinematic elements.


Ridgid - Spring - Smooth


the nodes involved in the connecion on the first mesh cannot move relative to each other as the spider connecting them is stiff - there is a beam between the two connections that has a spring stiffness behaviour - the nodes on the second mesh involved in the connection can move relative to each other (ie the connected nodes are not stiffened by the connection) and the movement of nodes relative to each other is dependent on their position relative to the master node, with the distribution of displacement done by the least squares method..

as far a documentation goes you need to look in the Finite Element Reference guide and not the generative structural analysis guide. The Finite Element Reference guide describes how ridgid and smooth, connections and spiders are implemented

 

[itsmyjob]

sounds good to me...

Eric N.
indocti discant et ament meminisse periti ​