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 are

Curve | Radial Curve |

Astroid | Quadrifolium |

Catenary | Kampyle of Eudoxus |

Cycloid | Circle |

Deltoid | Trifolium |

Logarithmic Spiral | Logarithmic Spiral |

Tractrix | Kappa Curve |

**References**

Lawrence, J. D. *A Catalog of Special Plane Curves.* New York: Dover, pp. 40 and 202, 1972.

Yates, R. C. ``Radial Curves.'' *A Handbook on Curves and Their Properties.* Ann Arbor, MI: J. W. Edwards, pp. 172-174, 1952.

© 1996-9

1999-05-25