[kitare102]

Looks like you might need to go into the realm of spring suspension if you're worried about coplanar contact. If you made the corner unit as a whole independent from the main frame, I think that would be a functionally sound way of pushing the mecs down into the floor surface. Obviously that would cause issues with lateral impacts, so depending on the amount of uneven wear expected between wheels, it would probably be better to just assure that all of the wheels are in the same condition and the axle is attached to the frame soundly.