According to the type of rotary axis, five-axis machine tools can be divided into three categories: five-axis with double turntable, five-axis with double swing head, and five-axis with single swing head with single turntable. There are two types of rotating shafts: the rotating shaft that rotates the spindle direction is called the swing head, and the rotating shaft that rotates the table that clamps the work piece is called the turntable.