结合金属板材件成形工艺,提出一种基于切口填补模型的金属板材件三维激光切割轨迹自动生成方法。利用切口面之间的凹边实现了切口特征自动识别和选取,并采用顶点偏置算法实现了激光束半径自动补偿。在对切口特征进行填补,构建切口填补模型的基础上,利用共享切口边的两个三角面片的法向量计算出激光入射点处的法向量,进而确定了激光头的姿态,使得激光束始终与被切割表面保持垂直。应用实例表明,上述算法可行,系统运行稳定可靠。
A method for automatically generation of sheet metal three-dimensional (3D) laser cutting path based on the incision filled model is proposed considering the sheet metal forming process. Automatic selection of incision features is realized through automatic recognition of incision features by using the concave edges between the incision faces, and the laser beam radius compensation is done through the offset of the edge loop of incision by using vertex offset method. On the basis of the incision features filling and the remodeling of the model, the laser head posture is determined using two normal vectors of the two triangles that shares the edge on which the laser beam points are located, which ensures the laser head perpendicular to the surface of workpiece in the whole process of laser cutting. The case studies show that the above algorithm is feasible and the system is stable and reliable.