Even though my team has never used mecanums, I’ve been thinking about them and the design challenge they pose.
So it got me thinking about making a CAD model, and while running the model through my head, the most obvious problem was the rollers.
so this is a puzzle for you: how would you model the rollers of a mecanum wheel?
to give everyone a chance, please post your method in a white font, requiring someone to highlight it in order to read it:
1)create a cylindrical roller, and a giant tube with an ID of the desired wheel OD. extrude cut with the tube (or use boolean subtraction: result=roller-tube). now the roller has a profile on it which can be used in order to revolve cut the rest of the roller.
this method is still somewhat convoluted in my opinion and I’d like to hear something easier and/or cleaner (or just any other creative idea!).
We found that two radii with a “point” between them was the optimal shape for rollers. This was through experimentation only, and I’m not sure of the math behind it. Since the parts are patterned, it’s simple to adjust the effective diameter by tweaking a single roller. Your mileage may vary, of course.
If R is the radius of your wheel and assuming that he rollers are the 45 degrees,
Draw an ellipse with major radius of R*sqrt(2) and minor radius of R
the axis of the roller will be perpendicular to the minor radius of the ellipse and the profile of the roller is the top of the ellipse where the minor radius crosses the perimeter.