针对复杂曲面通道零件多轴加工的刀具优化选择问题，提出一种基于点可行空间分析的刀具选择方法。分析了复杂曲面通道多轴加工刀具运动的几何约束，利用临界约束条件对通道加工的临界刀轴进行求解。通过分析单点可达区域与球头刀可行摆刀域之间的关系，提出一种无碰撞干涉条件下的最大刀具直径选择方法；在此基础上，通过对可行摆刀域内刀轴矢量的优化，获得了刀具直径最大条件下的最短刀具长度。以整体叶轮的五轴加工为例，对该方法进行了分析与验证，给出了叶片曲面上最大刀具直径与最短刀具长度的变化情况，并对不同刀具直径的加工效果进行了对比分析。结果表明，本文方法能获得复杂曲面通道类零件多轴加工的最大刀具直径、最小刀具长度，可显著提高该类零件的加工效率及加工稳定性。
This paper is devoted to selecting an optimal ball-end tool for machining channel parts with sculptured surface on the multi-axis machining. A method is proposed that based on analyzing the feasible tool orientation of a given single point. Critical tool directions are obtained by establishing and analyzing the mathematic model of cutting tool motion. After researching the differences between visibility direction on the single point and feasible tool orientation of a given ball-end, maximum tool size can be calculated without collision between tool and workpiece. Furthermore, minimum tool length is obtained according to optimize the feasible tool orientation after selecting maximum tool size. Finally, an impeller is machined in a five-axis machining to verify the validity and correctness of the presented approach. Meanwhile, the changes of maximum tool size and minimum tool length on the whole machined surface are given. The machining results used different tools are compared and analyzed. The results suggest that the maximum tool size and minimum tool length can be achieved for machining channel parts with sculptured surface by implementing the developed method, and the machining efficiency and machining stability can be significantly improved.
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