Epitrochoids and Hypotrochoids by mattmoses

Last crawled date: 3 years ago

This is a Public Domain OpenSCAD file with epitrochoids and hypotrochoids.
These shapes are useful for making mechanisms like
Roots Blowers http://www.thingiverse.com/thing:8068
Wankel Engines http://www.thingiverse.com/thing:8069
and Moineau Pumps http://www.thingiverse.com/thing:7958
An EPITROCHOID is a curve traced by a point
fixed at a distance "d"
to the center of a circle of radius "r"
as the circle rolls
outside another circle of radius "R".
An HYPOTROCHOID is a curve traced by a point
fixed at a distance "d"
to the center of a circle of radius "r"
as the circle rolls
inside another circle of radius "R".
An EPICYCLOID is an epitrochoid with d = r.
An HYPOCYCLOID is an hypotrochoid with d = r.
See http://en.wikipedia.org/wiki/Epitrochoid
and http://en.wikipedia.org/wiki/Hypotrochoid