Definition:Epitrochoid/Prolate

Definition
Let a circle $C_1$ of radius $b$ roll around the outside of another circle $C_2$ of radius $a$.

Consider a point $P$ on the line of a radius of $C_1$ at a distance $d$ from the center of $C_1$.

Let $d > b$.

The curve traced out by $P$ is called a prolate epitrochoid.

Also see

 * Definition:Epitrochoid
 * Definition:Curtate Epitrochoid


 * Definition:Epicycloid