Modeling Recommendation
For any 3D structure, we recommend enabling all six degrees-of-freedom (DOF) at each joint location. Rotational DOF may be removed only when an object does not have rotational stiffness, as is the case with cables, solids, and frame elements with all end moments released to simulate a truss structure.
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It is best to use the space-frame option since a space truss will restrain rotation and artificially support the structure if all moments are not released.
See Also
- Truss article