The present invention involves a method of adjusting path data for a motive body includes identifying four consecutive points of the path data. The four consecutive points include a first point, a second point, a third point and a fourth point. It is determined whether the second point is suitable for smoothing. If the second point is suitable for smoothing, then a first arc and a second arc are located, and the second point is moved into an area between the first arc and the second arc. The first arc is defined by the first point, the second point and the fourth point. The second arc is defined by the first point, the third point and the fourth point. A line move associated with the second point is replaced with at least one arc move associated with the second point.