局部刀具轨迹平滑过渡方法的研究

Research on the Method of Smooth Transition of Local Tool Path

当三轴机床沿线性轨迹运动时,其速度、加速度以及跃度在过渡点是不连续的,直接影响刀具的运动状态,从而降低曲面的精度。提出一种优化方法,通过在刀尖点相邻的线性位置插入三次B样条,从而获得满足误差限制条件、能够实现在连接点三阶连续的的最优刀具位置点样条曲线。通过该方法,可以使刀具在拐角处圆滑过渡,同时保持速度、加速度连续,避免刀具在拐角处产生接刀痕迹。最后通过一大拐角的实验证明该方法相对于传统的线性插补可以提高产品的加工质量。

When the three axis machine tool moves along the linear trajectory, its speed, acceleration and jerk are not continuous at transition points. It directly affects the movement state of cutting tool, so as to reduce the precision of surface. An optimization method was proposed, through the insertion of cubic B-spline at the adjacent position of the tip point, a continuous optimal tool position spline curve could be gotten which had three-order continuity at the connection point. By this method, the cutting tool can be smoothed in the corner, while the speed and acceleration are continuous, and the cutter trace can be avoided. Finally, the experimental results prove that this method can improve the processing quality of the product compared with the traditional linear interpolation.