基于三角网格曲面映射的数控高速加工刀轨规划

CNC machining tool path panning based on triangular mesh surface mapping

为进一步改善数控加工曲面的表面质量,提出一种针对三角网格曲面的螺旋刀具数控加工轨迹规划方法,在充分考虑刀具轨迹的几何与动力学特性以及三角网格单元特性的基础上,有效减少了抬刀次数,保持了刀具轨迹的连续性。该方法从网格边界轮廓曲线上的刀触点开始逐层偏置,在参数域上对刀触点进行规划,并拟合成螺旋轨迹,将其逆映射到网格曲面上得到螺旋加工轨迹。与传统的截面法和环切法相比,该算法可以生成一条具有边界一致性、轨迹光滑连续的、无需多次进退刀的高质量螺旋加工轨迹。

To further improve the surface quality of NC machining surface, a generation method of constant scallop spiral path based on triangular grid was put forward. Based on taking the geometry and dynamics characteristics of tool-path and triangular grid cell into account, the number of carrying knives was reduced effectively and the conti- nuity of tool-path was maintained. This method starting biased from cutter contact point on mesh boundary and planning biased cutter location point on parameter field site layer by layer. The spiral track was fitted with NURBS fitting algorithm, and the spiral tool-path was obtained by inverse mapping it on the meshes finally. The simulation results showed that the track met the actual processing requirements compared with that of traditional ways such as section method and circuit cutting method.