五轴数控加工后处理关键技术分析与实现

从后处理的角度,分析了五轴数控加工的非线性误差,指出了其影响因素;提出了利用齐次变换矩阵和正向、逆向运动学相结合的误差计算方法以及相应的误差补偿策略;同时,引入了刀轴矢量"平滑化"的概念,提出了基于四元数向量插值的新算法;最后,以一个离心压气机叶轮为例,进行了计算机仿真加工和五轴机床试切加工实验.实验结果表明,所提出的方法改善了曲面加工精度和表面质量.

An Analysis and Realization on the Key Technology of Five-axis NC Machining Post-processing

Based on viewpoint of post-processing,non-linear error of five-axis NC machining was analyzed and its influencing factors were presented.The error calculating method using the homogeneous coordinate transformation matrix together with forward and inverse kinematics and the corresponding error compensation strategies were proposed.The concept of tool axis vector smoothing was introduced and the quaternion vector interpolation algorithm was proposed.Taking centrifugal compressor impeller as an example,the proposed methodology was verified by computer machining simulation and a trial machining on a typical five-axis machine tool.Experimental results show that the algorithms presented can improve accuracy and quality of surface machining.