We're trying to fit spherical wheels to move a prototype vehicle rather than the circular one for our project. The advantages we see are greater acceleration due to smaller M.I (for the same mass of the wheels) and easy parking. I suggested the conventional electric motor principle for giving drive to the wheels. For steering, i think, by changing the orientation of the field, we could bring about a change in the rotational axis. Is this idea feasible? Im actually not sure about the steering part.