关键词: NURBS曲线, de Boor算法, 直线加减速, NURBS反向插补, 弓高误差

Abstract:

Since NURBS has its own particularities,a NURBS curve feedrate model was constructed based on de Boor algorithm. This model consisted two parts-feedrate adaptive control and pre-interpolation acceleration/deceleration(acc/dec).The chord error, shear acceleration and normal acceleration of whole interpolation period were monitored and controlled based on de Boor algorithm. In order to calculate the distance of deceleration zone of the NURBS curve, a concept of NURBS reverse interpolation was introduced,which was illustrated by linear acc/dec.This model feasibility has already been proved in real CNC system.

Key words: NURBS curve, de Boor algorithm, linear acc/dec, NURBS reverse interpolation, chord error