**free_rotation

Description

This rotation condition allows a boundary to be rotated about one of the coordinate axes (2 displacements are imposed), while the DOFs along the third axis remains free. The usefulness of this condition is obviously only for 3D problems.

Syntax

The syntax is the following:

**free_rotation nset  dir  [origin]  value  table

nset

Name of the node set upon which the condition is active.

dir

an axis about which the node set will rotate (d1 d2 or d3). The DOF acting along the given direction is free in the absence of other conditions acting on it.

origin

specifies an arbitrary point on the rotation axis (use vector notation, see ); it defaults to \((0.~0.~0.)\).

value

Base value (scaling factor, decimal number).

table

Name of a valid loading table.

**linear_free_rotation

Description

A linearized version of the **free_rotation condition for use in linear small deformation analysis. See linear_rotation for more discussion on this.