Epitrochoid
![epitrochoid spiralgraph](epitrochoid_spiralgraph.png)
epitrochoid.nb epitrochoid_movies.nb epitrochoid_movies2.nb
History
Description
Epitrochoid is a family of cycloidal curves, a special case of Roulette. See Epicycloid and Hypocycloid for detail. Many famous curves are special cases of epitrochoid. (See: Curve Family Index).
![epitrochoid](epitrochoidGen.png)
![epitrochoidGen](epitrochoidGen.gif)
Formula
Properties
Special Cases
h == 0, Circle.
b == h, epicycloids with q cusps, where q is the denominator of b written as a irreducible fraction.
a == b, limacon of Pascal. a == b == h, cardioid .
![epitrochoidLimaconGen1](epitrochoidLimaconGen1.gif)
![epitrochoidCardioidGen](epitrochoidCardioidGen.gif)
![epitrochoidLimaconGen2](epitrochoidLimaconGen2.gif)
a/2 == b == h, nephroid .
![epitrochoidNephroidGen](epitrochoidNephroidGen.gif)