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Unread 08-07-2010, 13:12
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Aren Siekmeier Aren Siekmeier is offline
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FRC #2175 (The Fighting Calculators)
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Re: bump-free mecanum wheels

Quote:
Originally Posted by Hawiian Cadder View Post
the curve of the mechanum rollers is the profile of an elipse where one dimension is the diameter of the wheel, and the other is that diameter divided by the sin of 45 degrees.
Which also happens to be a circle projected onto a 45 degree plane (or whatever angle your rollers are at). I just tried this in AutoCAD 2011. I made a 1/8 helix turn (circular arc projected up to the angle of the the helix) and revolved it around the endpoints of the arc. The important part here is that the line of revolution must be at the same angle of the roller. This puts the outermost part of the revolution at the profile line, so that the roller fits inside a cylinder (circular wheel) perfectly. Correct me if I'm wrong, but from my observation it seemed to be working very nicely. Unfortunately, I do not currently have Solidworks (the platform I'm familiar with), so I can't make a complete wheel to verify just yet.