I am simulating a very simple cable element under traction (I also tested pure flexion) : one node is fixed, and a force is applied to the end node.
For the code attached, the elongation of the beam is 9.61 mm, while, analytically, it should be 12.7 mm. I did the same simulation with BeamEuler element, and the result is indeed 12.73 mm.
With cable ANCF, even with lower force (divided by 10), the error is significant (1.11 mm vs 1.27 mm).
The problem is the same in flexion and the error does not seem to be linear.
When I increase the number of nodes in the builder, the error decreases but it remains significant (10.88 mm vs 12.7 mm with 1000 nodes instead of 1).
I am using these elements wrong ? I thought they were suitable for large displacement and could replace Beam Euler if no twisting or shear were present ?
Thanks a lot for the help,