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Unread 03-07-2010, 16:43
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bump-free mecanum wheels

There's two things that are necessary to have bump-free mecanum wheels:
1) The contact surface of consecutive rollers must overlap.
2) The contact surface of the roller must correspond to the radius of the wheel.
It's the second one that I'm having trouble creating a drawing for, and I'm not sure that it's *possible* with Inventor. (Note that all drawings shown are in orthographic view)

The way I tried to create the contour was by slicing a cylendar at a diagonal.


However, when I radially extrude the profile, it extends outside the intended radius.



I grabbed a copy of the AndyMark wheels, and found they had a similar issue. This is shown with a circle drawn to one of the ends of the rollers. (The circle is concentric to the center of the wheel, parallel to the aluminum plates)


The issue, it appears, is slice needs to be non-linear. Are there 3-dimensional constraints that could be used instead of a slice?

(Sorry about the large pictures. I'm assuming that no-one is doing CAD on a screen smaller than 1024x800)
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