Nodes: Connection between structural entities or graphical entities
Nodes are the simplest objects.
There two kind of nodes : Structural and Simple.
?Structural nodes have X,Y,Z coordinates and six degrees of freedom
?Simple nodes have only X,Y,Z coordinates.
User does not specify the type of node when drawing, this is done automatically by the software.
To set node coordinates and properties:
All nodes have a position in space and a set of constraints
If single node properties have been used the Coords Panel
will be visible where the current node position can be read and modifed.
Note:
In Edit Selection mode the panel will not be active
Each node has three restraint conditions :
?Form Find Restraint
?Non Linear Restraint
?Linear Restraint
These restraints are set in this dialogue box.
The buttons Fixed and Free on the right side will check/uncheck all
restraints with a single click.
Node restraints panel
To understand how these restraints are used internally we must go into
detail and see what happens when a FormFind or Static Nonlinear analysis
is performed.
When we ask to do a formfind :
?All groups are merged into a single model
?Form Find Restraints are set as current
?Nodes at a distance < Welding Precision are merged in a single node
and their restraints are OR'ed
?The Form Find is processed
?Non Linear Restraints are set as current
?If internal reaction forces are present a nonlinear analysis is performed to relax
these forces ( this will happen if a node has different Linear and NonLinear restraints )
?Linear restraints are set as current
?If internal reaction forces are present a linear analysis is performed.
Of course, it isn't easy to understand all of this, so it will be explained
later in the tutorials section.
Note:
Welding precision can be set in the Settings
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