五轴联动数控加工进给率规划方法

摘要

This paper proposes a feed rate planning method to solve the velocity fluctuation problem in both machine tool coordinate system and the workpiece coordinate system.The velocity fluctuation of the tool tip point, which occurs in simultaneous five-axis NC machining if a constant feed rate is used, can be decreased.The kinematic transformation between the machine coordinate system and the workpiece coordinate system is first derived.The feed rate in every block of the NC code is then generated by considering the velocity and acceleration constraints in the two coordinate systems.The developed method has been integrated into a post-process system.Simulation results show that the machining time with the generated feed rate is 32.9％ shorter than that of the constant feed rate, and the velocity of the tool tip point becomes smoother.%针对五轴联动数控加工中恒定机床进给率下加工刀尖点速度波动的问题,提出了同时考虑机床坐标系和工件坐标系下运动学性能约束的进给率规划方法.首先推导了机床坐标系和工件坐标系之间的运动学变换关系,然后综合考虑了机床各轴运动速度和加速度约束条件,以及刀尖点与工件相对运动速度与加速度约束条件,对各程序段中的机床进给速度进行规划.将该方法主要应用于后置处理,仿真结果表明,规划进给率后,加工时间比恒定进给速度下缩短了32.9%,加工速度更为平滑.