Introduction A machine tool is a processing machinery, typically used to manufacture and fabricate various kinds of devices and machine parts, which is known as the “mother of machinery”, also called “machining center”. Generally speaking, a machine tool can be powered by a variety of sources. When machine tool powers on, it is able to move solid materials and perform various operations such as cutting, milling and drilling, etc. by physical and chemical force or other methods. In the cutting process of computed numerically controlled (CNC) machine tools, a high level processing precision is essential.