数控编程中,不仅要关注程序语句逻辑正确,还要关注加工精度问题.用直线拟合法编制椭圆轮廓数控加工程序时,首先要计算逼近误差,然后根据逼近误差确定各节点步距.通过数学推导,得到等间距和等角度直线逼近椭圆轮廓曲线时的逼近误差计算公式,可用于编制椭圆轮廓数控加工程序时确定循环语句或条件跳转语句的步距,提高椭圆轮廓加工精度.给出了确定步距的一些技巧.
In CNC programming,attention should not only be paid to the logical correctness of program statements,but also to the issue of machining accuracy.The approximation error should be calculated first,and then the step distance of each node should be determined according to the approximation error.When the NC machining program of elliptical contour is compiled by the straight line fitting method.The calculation formula of approximation error of equidistant and equiangular straight line approximation to elliptic contour curve is derived mathematically.It can be used to determine the step distance of loop statements or conditional jump statements when programming elliptical contour CNC machining programs,and improve the accuracy of elliptical contour machining.Some techniques for determining step spacing are also provided.