中文摘要：

基于中轴变换思想，提出了一种平面域数控加工的多尺寸刀具优化选择方法．根据给定平面域的中轴变换结果，以最大中轴变换圆为依据，确定粗加工的刀具直径，并规划相应的环切法刀具路径和残留的未加工区域；根据残留未加工区域对应的中轴变换结果，确定清角加工的刀具直径和刀具路径，重复该过程直至完成清角加工；最后进行清根加工．该方法有助于数控加工刀具的合理选择，缩短切削路径的长度，从而提高加工效率，可用于模具型腔的数控加工．

英文摘要：

The optimal selecting methods of the multiple cutting-tool sizes of 2D NC machining are dealt with based on the medial axis transform （MAT）. The cutter size of the rough machining and the tool-path of loop method and residual unmachined area are determined according to the maximum medial axis circle resulting from the MAT of the given boundary. Based on the MAT results of the residual unmachined area, the cutter size and the tool-path of each clean-corner machining process are generated. This process is repeated to the finish of clean-corner machining. The clean-root machining process is performed finally. The generated methods are very helpful to the optimal selection of the cutter size in NC machining, thereby the length of the tool-path can be shortened and the machining efficiency is improved. The proposed method can be used for pocket NC machining.