Curvature
Given a parametrized curve
where
Intuitively, the curvature measures how much the curve “bends”. A.k.a, a small curvature means the curve is flat, and a large curvature means the curve is tighter.
Curvature in 3D
The general definition of curvature is not that easy to use in practice. But in 3D, the formula can be simplified:
where