The curvature and torsion: how to distinguish the shape of a curve 
Still curvature and torsion
For a curve to be actually planar there are only two possible choices for each Frenet-Serret frame that must be fixed. In the app, these choices are given by frames corresponding to \(0º\) and to \(180º\). Observe that, once more, that the Frenet-Serret frame considered in \(180º\) is exactly the same as the one in \(180º\) (because the rotations with angles \(180º\) and \(-180º\) are equivalent).
