An interpolation algorithm based on improved S-type velocity planning and Steffensen-like parameter calculating was proposed in order to improve accuracy of non-uniform rational b-spline (NURBS) interpolation and reduce feedrate fluctuation. The adaptive interpolation method was used to obtain information of each curve segment. S-type velocity planning method was improved by adaptively adjusting jerk and accurately controlling feedrate based on the information of curvature of these segments. Then the optimal interpolation that satisfied all the error constraints everywhere was realized. The proposed algorithm determined the starting point of deceleration area precisely by the way of positive and reverse interpolation. Steffensen-like method with parameters was used to calculate the interpolation parameters without derivative calculation in order to improve real time performance and to control feedrate fluctuation availably, The experimental results show that ,the proposed method can effectively improve the interpolation accuracy and reduce feedrate fluctuation compared to other methods.
WEI Dong,ZHANG Shu you,LIU Xiao jian. NURBS curve interpolation algorithm with high accuracy and minimal feedrate fluctuation. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2016, 50(11): 2215-2223.
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