释义 |
Osculating SphereThe center of any Sphere which has a contact of (at least) first-order with a curve at a point liesin the normal plane to at . The center of any Sphere which has a contact of (at least) second-order with at point , where the Curvature , lies on the polar axis of corresponding to . All theseSpheres intersect the Osculating Plane of at along a circle of curvature at . The osculating sphere has center
where is the unit Normal Vector, is the unit Binormal Vector, is theRadius of Curvature, and is the Torsion, and Radius
and has contact of (at least) third order with .See also Curvature, Osculating Plane, Radius of Curvature, Sphere, Torsion (DifferentialGeometry) References
Kreyszig, E. Differential Geometry. New York: Dover, pp. 54-55, 1991.
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