A method and apparatus for positioning a manufacturing tool. A wheel assembly comprises a wheel plate and rollers. The wheel plate has a perimeter and an axis of rotation that is tiltable about a tilt axis. The rollers are arranged near the perimeter of the wheel plate, each of the rollers having an axis of rotation parallel to the tilt axis. An apparatus comprises an upper frame, a lower frame associated with the upper frame, a wedge slideably located between the upper frame and the lower frame, and a force applicator associated with the wedge.