A rotor is for angularly displacing a work piece about a central axis and includes an annular, central axial portion centered about the axis and having opposing, first and second axial ends and inner and outer circumferential surfaces. An outer radial portion extends radially-outwardly from the first axial end of the central portion such that an outer generally annular cavity is at least partially defined between the central portion and the outer radial portion. Further, an inner radial portion extends generally radially-inwardly from the second axial end of the central portion such that an inner generally annular cavity is at least partially defined between the central portion and the inner radial portion. One or more motor stators are disposed at least partially within the outer or inner cavity and are each configured to angularly displace the rotor about the central axis, and preferably contactlessly drives the rotor.