Fix Constraint

The fix constraint is the most basic type of single-point constraint in Femora. It applies constraints to specific degrees of freedom at individual nodes.

Description

The fix constraint works by directly specifying which degrees of freedom should be constrained at a particular node. Each degree of freedom can be set as either free (0) or fixed (1).

Parameters

node_tag (int): The tag (ID) of the node to be constrained
dofs (List[int]): List of DOF constraint values (0 or 1) * 0 = unconstrained (free) * 1 = constrained (fixed)

Usage

import femora as fm

# Create Femora instance


# First assemble the mesh
fm.assembler.Assemble(merge_points=True)

# Apply fix constraint to node 10
# Fix translations (DOFs 1,2,3) but allow rotations (DOFs 4,5,6)
fm.constraint.sp.fix(node_tag=10, dofs=[1, 1, 1, 0, 0, 0])

# Fix all degrees of freedom at node 20
fm.constraint.sp.fix(node_tag=20, dofs=[1, 1, 1, 1, 1, 1])

# Fix only X direction at node 30
fm.constraint.sp.fix(node_tag=30, dofs=[1, 0, 0, 0, 0, 0])