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A comment on Should Quadrotors All Look Like This?. Parent comment

Re:Should Quadrotors All Look Like This? by aaren on Thursday November 14, 2013 @04:55AM (#6731519)
Can you explain why?

Is it to do with the bulk properties of the materials not varying with scale? Or scaling with some power of length < 3?

If you tried to spec a full sized helicopter engine to make speed changes like those in the video would it tear itself apart?

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Re:Should Quadrotors All Look Like This? by barrkel on Thursday November 14, 2013 @07:56AM (#6731999)
Yes.

Mass increases with the cube of scale, while structural material cross-section area increases only with the square of scale. So insects can have miniscule legs, while elephants have tree trunks, proportionally.

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Re:Should Quadrotors All Look Like This? by mturmon on Thursday November 14, 2013 @12:11PM (#6733524)
Right, sometimes called "square-cube law" (http://en.wikipedia.org/wiki/Square-cube_law). Worth knowing about so you can explain to yourself the differences noted above.
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Re:Should Quadrotors All Look Like This? by jamesaguilar on Thursday November 14, 2013 @11:45AM (#6733321)
Think about it. Ants can carry six times their weight, while larger creatures could never accomplish that. I don't know the physics behind it, but it's not hard to see that small things can have greater strength per mass than large things.
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