Ok, I’m sorry, I’m French… :o
“Ball bearing” is the google translation for “roulement à billes” in French… ^^
I tried to draw this :
![http://weapic.com/img/a37d49b8670233e14e2aeedc29fe2190_roulement a billes.png](http://weapic.com/img/a37d49b8670233e14e2aeedc29fe2190_roulement a billes.png)
The top plate turn with the central tree but the bottom plate is static.
My problème in the next blend is to rotate the little plane for the empties to be points of this plane (as much as possible).
So I tried to add four objects which are tracking to the empties and then I want to make the plane the normal of these objects…I used four copy rotation constraints with an influence of 1.0, 0.75, 0.5, 0.25. But it doesn’t work.