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Unread 14-02-2011, 15:02
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Re: 4" Wooden Mecanum Wheel

Quote:
Originally Posted by TheOtherGuy View Post
I found the cross section of two ellipses of vertical radius equal to the radius of the wheel and a horizontal radius of the wheel radius * sqrt(2).
The correct profile is actually closer to a parabola than an ellipse. If you're a purist, you might find these of interest:

roller profile parabola vs ellipse comparison:
http://www.chiefdelphi.com/media/papers/download/2750

parabolic profile roller projection to XY plane forms circular arc :
http://www.chiefdelphi.com/media/papers/download/2751

Equations for "bump-free" mecanum roller profile:
http://www.chiefdelphi.com/media/papers/download/2749

Win32 "bump-free" mecanum roller profile calculator:
http://www.chiefdelphi.com/media/papers/download/2770

bump-free mecanum roller equations (alternate derivation):
http://www.chiefdelphi.com/media/papers/download/2777




Last edited by Ether : 14-02-2011 at 15:06.