I go on with my bike mowing device, trying to find verticality not only for the biker, but for the wheels as well.. (see the video).
However, if my assembly does have the wheels to keep verticality, it's all due to a single constraint of parallelism, between the vertical rod and a line joining the center of two balls. In short, it's all a numerical and geometrical relation.
Please, would anyone be willing to help me translate this relation in a mechanical one, using parts ?