Following our previous experiments with elliptical cycloids, here we show an elliptical hypocycloid.
Again, the project is to derive a formula to draw the curve produced by the path of the blue dot.
One obvious difference is the rotation of the circle about its center. This hypocycloid requires the circle to rotate in the OPPOSITE direction than it is revolving around the INSIDE of a curve. Note that it is revolving clockwise around the ellipse, but rotating counter-clockwise on its center.
For an epicycloid it must rotate in the SAME direction.