Dave Looman
Ansys Employee

This isn't a typical application with a well-established approach.  If the wheel is relatively rigid, the horizontal force required to push the wheel over a cobblestone could be calculated by hand, based on the angle between a line from the center of the wheel to the touching point of the wheel and the cobblestone and the weight per wheel.  A more realistic analysis would connect the four wheels with a rigid frame and assume only 1 or 2 wheels were being lifted over a cobble stone at a time.  Rubber tires would help moderate the force required.  A static structural analysis should be adequate.   Point masses can be used to model the weight.