Let be a curve and let
be a fixed point. Let
be on
and let
be the curvature center at
. Let
be the point with
a line segment parallel and of equal length to
. Then the curve traced by
is the radial curve of
. It was studied by Robert Tucker in 1864. The parametric equations of a curve
with radial point
and parameterized by a variable
are given by
| (1) | |||
| (2) |
Here, derivatives are taken with respect to the parameter .