Abstract: A solution of establishing the universal models is proposed to overcome the disadvantages of cycloid rotational indexing CNC machine tool, in which three sorts of universal model are brought forward. Based on defining of cycloid rotational indexing machining and mathematic description about cycloid, the relation between cycloid parameters and cycloid trails, i.e. the relation between cycloid parameters and the track of knifepoint, is studied. According to the cycloid trails and the characteristics of various shapes to be machined, the workpiece is divided into three sorts. They are the kinds of even polygon, and slot on the end plane, odd polygon and involute. Mathematic models are established for every sort respectively, and are integrated into numerical control system of the machine, so that certain extent universal characters are embedded into the machine. The validation of the developed models is proved through machining the sample parts.

Key words: Cycloid, Machining method, Mathematic, model, Numerical control system, Rotational indexing