基于空间运动学的传统机床与 Free-form 型 机床运动转换方法的研究

从空间运动学的观点来看，为保持加工过程中刀具与工件之间的相对位置不变，传统机床与Free-form型机床的运动转换只需进行2次矢量旋转即可简单实现。然而现有的CNC系统不可能在加工时对齿面的每一点进行转换，因为这满足不了实时性的要求，而且也无必要。因此作者提出了一种简单的方法，即只在齿面参考点进行转换，通过空间相对运动高阶加速度的分析，就可得到Free-form机床的所有调整参数，文中推导了这种转换方法的精确转化公式。与其他方法相比，介绍的方法概念清晰，计算量小，更加简便而准确。最后给出了计算实例以验证本文方法理论和算法的正确性，其TCA分析结果表明，这种以参考点为基础的转换方法是完全可靠的。

STUDY ON KINEMATIC TRANSFORMATION FROM TRADITIONAL MACHINE TOOL TO FREE-FORM ONES BASED ON SPATIAL KINEMATICS

From the spatial kinematic point of view,in order to keep the relative position between the cutter and work piece unchanged,the kinematic transformation from traditional machine tools to free form ones can be simply realized by two times of vector revolution.However,available CNC system cannot perform the transformation for each data point during the machining process at real time,nor being it necessary in practice.Therefore,a simple algorism put forward is,it is only necessary to perform the transformation at the reference point,and by means of analyzing the higher order spatial acceleration,all the setting parameters for free form machine tools can be determined.Accurate formulas for transformation are deduced.In comparison with other methods,this algorism has the advantages of clear in principle,less calculative amount,simpler and more accurate.An?example is also given to verify the algorism,and from the TCA result it is proved that the transformation based on the reference point is reliable.