Quote:
Originally Posted by Hector
|
Hector and I have been discussing this offline.
Cutting a cylinder with a plane at 45 degrees creates an ellipse which gives an approximately correct roller profile which should suffice for most applications.
But if you are a perfectionist, there's a mecanum roller design calculator available
here which generates a theoretically correct XY data file so that the rollers create a perfectly circular wheel circumference. Hector has been kind enough to test this by running the calculator and CAD'ing up a model to verify the algorithms used in the calculator.
The user enters the desired radius of the effective wheel circumference, the desired roller radius at the center of the roller, and the desired number of rollers per wheel. The program then calculates the roller clearance, the rotor length for no gaps at the circumference, the roller end-radius at this no-gap length, and an XY data file for the roller profile. It is easy to iterate the radius to find the largest radius that still leaves an acceptable clearance between the rollers.
I believe Hector is working on a CAD-only process to achieve the same result.