Study on Acc/Dec Algorithm Based on Piecewise Polynomial in CNC

Abstract

Abstract. In order to improve the stability of feed movement in high speed CNC system, the feedrate planning algorithm based on piece-wise polynomial function was proposed. The flexible transition of feedrate was realized through maintaining linear continuous jerk. The principle of the proposed algorithm was introduced and the method to generate smooth motion profile based on the proposed algorithm was presented. The rapidity, stability and tracking accuracy of the feedrate planning algorithm to linearity, S curve and the proposed one were analyzed. The proposed algorithm is simple and it can be applied in acceleration/deceleration before interpolation in high speed feed movement to improve the stability of it. The proposed algorithm was applied in multi-contour high speed processing and the result indicated that it could improve the stability of large-scale parts motion.

Study on NURBS Curve Interpolation Based on before Acceleration/Deceleration with Linear Jerk

“…Yeung and Altintas et al have pointed out the cubic acceleration leads to much smoother position commands with continuity in velocity, acceleration and jerk, which is better suited for high speed machining and precision drives, but at the expense of increased computional load on the CNC computer [11]. Based on the piecewise polynomial acceleration/ deceleration algorithm with linear jerk evolution proposed by Ji et al [12], a novel NURBS interpolation method was put forward in the present work.…”

“…Considering the machine tool's capability standing against the vibration, the maximal jerk and change rate of jerk are selected properly. The feed and acceleration can be planned with all those parameters with linear jerk and S curve acceleration/deceleration as described in [3,12].…”