六轴混联数控机床曲面加工方法研究

摘要

Because the movements of the cutter of a hybrid NC machine tool in Cartesian space are the nonlinear mappings of servo motions in a joint space, its motion axis can not be directly used for the drive servo motion. Taking into account the structural and motion characteristics of a six-axis hybrid NC machine tool, we study its motion control algorithm, establish its motion control model and derive the mapping relationship of its parallel mechanism from virtual axis space to real axis space. With the experiments on the fine machining of the curve surface of a polishing plate, we analyze the conditions that interfere the cutter shank and the workpiece, present its rough curve interpolation method and propose a new motion control algorithm for simultaneously moving the serial mechanism and parallel mechanism of the six-axis hybrid NC machine tool. The experimental results verify the feasibility and effectiveness of our method for machining its curve surface.%由于混联机床采用了并联机构，刀具在笛卡尔空间的运动是关节空间伺服运动的非线性映射，因此普通数控加工用的运动轴不能直接用于驱动伺服轴运动。结合六轴混联机床的结构特点和运动特性，针对混联机床数控加工中的运动控制算法问题进行了深入研究，建立了混联机床的运动控制模型，推导了并联机构的虚实映射关系。结合研磨盘曲面的精加工，分析了刀柄与工件不发生干涉的条件，给出了圆弧粗插补方法，提出了基于混联数控机床的曲面加工的运动控制算法，加工试验验证了方法的有效性和可行性。