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I'm looking for the name of a shape that is like a capsule, but where each circle can have different radii. The shape could be described using two circles (two centers and two radii). Something like this (this is a 2D shape, not a lame attempt at 3D):

figure

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    ImageShack seems to have deleted your image, and replaced it with an ad banner. If you can, please reupload the image (or something equivalent) using the image upload button in the editor toolbar (which will upload it to Stack Exchange's imgur account).2015-08-17

3 Answers 3

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You can just say it is the convex hull of two circles.

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    Yeah that's a simpler definition. A name would be cool though, as I'd like to use it as the name of a class in a program and ConvexHullOfTwoCircles is not too catchy.2010-07-31
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    What about Pear?2010-07-31
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    It looks like a pulley and belt system, so how about PulleyBeltShape?2010-07-31
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    I'm accepting this because the shape doesn't seem to have a name and this is a helpful definition.2010-07-31
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    @Qiaochu Haha, Pear's not bad but, if you're into fruits, Avocado seems more fit!2010-07-31
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Here is an article at Mathworld on Circle-Circle Tangents. Perhaps "CirclesWithTangents"?

Circle-Circle Tangents
(source: wolfram.com)

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    Hmm... not too sure for the name, but thanks for that article, it should be helpful with what I intend to do with this shape.2010-07-31
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    @Dennis Williamson Circle with Direct tangents2014-09-05
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I would suggest the name "Capsuloid". I had the same question but in $3D$. One could define the capsuloid ratio as the quotient of smallest radius $r$ to biggest radius $R$. $r\over{R}$ belongs to $[0,1]$, a value of $1$ corresponding to a true capsule.

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    Please use Mathjax2017-07-18
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    Oh great I didn't know it was available! Super noob here :) Thanks!2017-07-19