对置正交多回转轴机床刀具姿态优化算法的研究

Research on Tool Posture Optimal Algorithm of Opposed Orthogonal Multi-rotation Axis Machine Tool

叶轮叶片是航空发动机核心零部件,其加工精度对发动机的性能有重大影响,加工效率制约着加工成本。针对叶片特征前后缘螺旋加工方式刀轴曲率变化过大导致加工过程中机床轴负载不均衡的问题,提出了机床轴负载增量均衡的叶片缘面加工刀具姿态优化模型,采用粒子群算法对刀轴进行优化。以某航空叶片为对象进行了试验验证,分析该叶片特征前后缘处螺旋轨迹刀具姿态优化前后路径,对两种路径采用虚拟等步长分析方法在五轴联动对置正交回转轴机床上进行运动性能分析,获得机床各回转轴的速度和加速度绝对值曲线,结果显示优化后路径能使各回转轴绝对角加速度标准差明显降低。

Impeller blades are the core components of aero-engines,and their machining accuracy has a significant impact on the performance of the engine,and the machining efficiency restricts the machining cost.Aiming at the problem that the load of machine tool shaft is not balanced in machining process due to the excessive change of tool shaft curvature in the helical machining of blade characteristics,a tool attitude optimization model of machine tool shaft load increment equalization is proposed,and the tool shaft is optimized by using particle swarm optimization.An aerospace blade is used as the object to test and verify,the spiral path at the front and rear edges of the blade feature is analyzed to optimize the front and back path of the tool posture.The virtual equal-step analysis method is used to analyze the kinematic performance of the two paths on a five-axis linkage opposed orthogonal rotary axis machine tool.The absolute value curve of the speed and acceleration of each rotary axis of the machine tool is obtained.The results show that the optimized path can significantly reduce the standard deviation of the absolute angular acceleration of each rotary axis.