基于机床运动学约束球头刀多轴加工刀轴矢量优化方法

针对目前航空发动机叶片进排气边加工精度和表面质量较差的问题，提出了一种基于机床运动学约束球头刀多轴加工刀轴矢量优化方法。建立刀位优化变量与刀位数据之间的关系方程，同时建立刀位数据与机床回转轴角度之间的运动变换方程，从而推导出刀位优化变量与机床回转轴角度之间的关系方程。通过求解上述方程得到球头刀多轴加工复杂曲面的刀轴矢量计算公式。在此基础上，给出球头刀多轴加工刀轴矢量优化方法和刀轨生成方法。同时，以某航空发动机叶片为例，分析了本文算法和Sturz算法对机床回转轴角度的影响。分别利用本文算法和Sturz算法生成该叶片进气边加工的刀轨，并在五轴数控机床上进行加工试验。试验结果表明，该算法能够避免加工过程中机床回转轴的大幅波动，使机床轴运动更加平稳和光滑，从而提高曲面的加工质量和加工效率，具有一定的实际应用价值。

Tool Orientation Optimization Method Based on Kinematics Constraints of the Machine Tool in Multi-axis Machining with a Ball-end Cutter

In order to solve the problem of the poor machining quality of the leading and trailing edge surface of the aero engine blade, a tool orientation optimization method based on the kinematics constraints of the machine tool in multi-axis machining with a ball-end cutter is presented. A relation equation between the design variables of tool position and cutter location (CL) data is established, and a coordinate transformation equation between CL data and rotary axes of the machine tool is established. From the above two equations, a relation equation between the design variables of tool position and rotary axes of the machine tool is derived. Through solving the above relation equation, formulas for calculating tool position and tool orientation during the machining of sculptured surfaces with a ball-end cutter are derived. On this basis, a tool orientation optimization method and a tool path generation method for multi-axis machining with a ball-end cutter is presented. Besides, analyze the influence of the proposed method and Sturz method on rotary axes of the machine tool. Tool paths of the leading edge surface of an aero engine blade are generated by the proposed method and the Sturz method, respectively, and cutting trials are carried out on a five-axis machine tool. Experimental results show that the proposed method can avoid abrupt change of rotary axes of the machine tool and make the movement of machine axes more stable and smoother, and further obtain better machining quality and higher machining efficiency. Consequently, the proposed method will have important practical value.