Circle of Curvature

You may redefine the vector-valued function by clicking on c(t).

c = CurveCartesian(t, sin(t), t, -6.28, 6.28)
A = Point(c)
N = UnitVector(Vector[CurvatureVector[A, c]])
a = Tangent(A, c)
T = UnitVector(a)
d = OsculatingCircle(A, c)
k: abs(Curvature[A, c])
B: A + N / k