A fully enclosed five-axis machining center refers to a processing mode of CNC machine tools, where the five axes represent five coordinate axes on the CNC machine tool, including three linear axes and two rotational axes. These five coordinate axes can operate simultaneously and coordinately under the control of the computer numerical control (CNC) system to perform high-speed engraving and milling on workpieces. This processing method is suitable for machining parts with complex geometric shapes because the tool can be positioned and connected with five degrees of freedom. Specifically, the composition and motion of a CNC five-axis machining center machine tool include the following forms.