数控加工仿真中切削几何参数的计算方法

Determination of Cutting Geometrical Parameters in NC Machining Simulation

为实现以切削力和去除率为参考的进给率优化策略,研究加工仿真中材料切削几何参数的计算方法.采用双层次八叉树体素模型表达加工工件,隐式曲面方程表达刀具扫描体,依据灰色体素中三角面片的位置信息计算有效体积系数,在材料去除仿真的布尔减运算中计算去除率、切削深度和宽度,最后,推导出进给率与材料去除率的关系式,依据给定的去除率参考值可求出进给率优化值.实验表明,在材料去除仿真过程中能够准确计算去除率、切削面积、切削深度和宽度,利用优化关系式可以得去除率约束条件下的进给率优化值.

In order to realize strategy of feed rate optimization with reference to the cutting force and removal rate, the determination of the geometrical parameters of material removal in machining simulation is proposed. The dual-octree voxel model is used to represent the workpiece, and the implicit surface is used to represent the sweep volume of tool. The effective volume coefficient is calculated based on the position relationship of triangular patches in the gray octants. During the boolean subtraction of material removal simula- tion, the parameters of material cutting is performed about removal rate, cutting depth and width. Finally, the relationship between feed rate and material removal rate is deduced. According to the given removal rate reference value,the optimum value of feed rate can be determined. The experimental results show that removal rate,cutting area, cutting depth and cutting width can be calculated accurately in the process of material removal simulation, and the optimal value of feed rate under the constraint of removal rate can be obtained by optimizing the relationship.