where the unit Tangent Vector and unit ``principal'' Normal Vector are defined by
Here, is the Radius Vector, is the Arc Length, is the Torsion, and is the Curvature. The binormal vector satisfies the
See also Frenet Formulas, Normal Vector, Tangent Vector
Kreyszig, E. ``Binormal. Moving Trihedron of a Curve.'' §13 in
Differential Geometry. New York: Dover, p. 36-37, 1991.
© 1996-9 Eric W. Weisstein