Talk:Hypotrochoid

Hypotrochoid

Is there a diagram or picture of this movement or design? Anything to illustrate the word. — Preceding unsigned comment added by 70.183.237.150 (talk • contribs) 14 August 2006‎

(Animations have now been added to the article. - dcljr (talk) 20:26, 20 October 2015 (UTC))

File:HypotrochoidOutThreeFifths.gif to appear as POTD soon

Hello! This is a note to let the editors of this article know that File:HypotrochoidOutThreeFifths.gif will be appearing as picture of the day on July 25, 2010. You can view and edit the POTD blurb at Template:POTD/2010-07-25. If this article needs any attention or maintenance, it would be preferable if that could be done before its appearance on the Main Page so Wikipedia doesn't look bad. :) Thanks! howcheng {chat} 18:00, 23 July 2010 (UTC)

Picture of the day

An animated image showing the construction of a hypotrochoid (view animation), a roulette curve traced by a point attached to a circle of radius r rolling around the inside of a fixed circle of radius R, where the point is a distance d from the center of the interior circle. The red curve is a hypotrochoid drawn as the smaller black circle rolls around inside the larger blue circle. The Spirograph toy traces out hypotrochoids, as well as epitrochoid curves.Image: Sam Derbyshire

Moving the larger circle instead

What is it called when the moving circle is actually larger than the fixed one, not smaller? I don't mean an epitrochoid, where the moving circle is rolling around on the outside of the fixed one; I mean basically take the exact same initial setup shown here to illustrate a hypotrochoid (smaller circle inside and tangent to larger one), but then attach the point to the larger circle, and move the larger circle "around" the smaller, now-fixed, inner circle. What's that called? Is it still called a hypotrochoid? - dcljr (talk) 20:47, 20 October 2015 (UTC)