基于五次速度曲线的高柔性加减速前看算法

A High-flexible Acc /Dec Look-ahead Algorithm Based on Quintic Polynomial Feedrate Curve

为了减小机床振动,提高连续小线段加工速度,提出了一种基于S型加减速的前看插补算法。采用五次多项式速度曲线,可以实现加速度和跃度的连续变化。首先根据NC代码的目标进给速度、机床动力性能和微段几何特征预求速度约束,然后反向扫描求解满足减速要求的速度约束,最后根据线段长度规划出约束之下的速度曲线,发送至位控模块进行实时运动控制。集成到三轴数控试验平台上试验,算法运行稳定,大大提高衔接速度,仿真结果表明加工时间比传统插补算法缩短了77.31%。

This paper proposes a interpolation algorithm to reduce vibration and optimize the junction feder- ates between consecutive small line segments. Quintic polynomial is used to ensure the continuities of accel- eration and deceleration. First, the algorithm calculates the initial feedrate constraints according to NC code, machine dynamic performance and geometrical characteristic of the lines. Next, the constraints are recalcula- ted from the end of the preprocessing segments so that the feedrate can decelerate to an expected value. At last, the optimized feederate curve is planed regarding the constrains and the lengths of the lines, and the re- sults are sent to the real-time position control module, and reduce the cutting time. When integrated into 3- axis CNC system, simulations indicate that the method can greatly increase the jounction feedrates, and re- duce the cutting time by 77.31% compared to the conventional methods.