实轴空间综合约束下的数控加工速度前瞻策略

为了避免数控高速加工中由高曲率区域引起的机床驱动轴的运动突变、机床振动和工件过切,提出了基于实轴空间综合约束的数控加工速度前瞻控制策略.该方法应用切削运动的S形曲线速度规划方案,对机床实轴运动数据进行速度、加速度、冲击约束检测,整体提前寻优确定S形速度前瞻的过程参数,并提出了速度规划节点分离法对切削路径进行分段独立S形曲线速度的规划.仿真和试验表明,采用该方法进行速度前瞻处理时,可使加工速度平滑连续,不仅消除了各驱动轴运动突变引起的冲击振动,而且有效地解决了五轴数控加工中的速度控制问题,因此降低了曲面轮廓误差,满足了高速高精度的加工要求.

CNC Machining Velocity Look-Ahead Strategy Restricted by Machine Axis Drive Ability

In high curvature region of high speed computer numerical control(CNC) machining,machine axis motion shock,mechanical vibration and cutting overshoots often occur.A novel CNC machining velocity look-ahead strategy based on machine axis drive ability constriction is proposed.The S-curve velocity planning is utilized,and the velocity planning parameters are achieved by checking the velocity,acceleration and jerk of the rotate axis and linear axis on the tool path.Then a velocity control node subsection is suggested to divide the cutting path into independent sections to implement the velocity planning independently.The simulation and experiments demonstrate that the strategy enables to smooth the cutting motions and obviously improve the machining surface quality,and 5-axis CNC velocity control is thus effectively solved to meet the high performance requirements in free-form surface machining.