非均匀有理B样条曲线的高精度低速度波动插补算法

NURBS curve interpolation algorithm with high accuracy and minimal feedrate fluctuation

为提高非均匀有理B样条曲线的插补精度,降低插补速度波动率,提出一种基于改进S型速度规划及Steffensen型参数计算的插补算法.通过自适应插补得到曲线分段信息,根据曲率信息自适应调整最大加加速度并进行速度精确控制,改进了传统S型速度规划算法,使得插补处处满足误差约束。采用正反向插补精确确定减速点,并利用带参数Steffensen型方法计算曲线插补参数,避免求导运算,增强插补实时性,有效控制速度波动率.实验结果表明,相对于其他算法,该算法具有更高的插补精度、更低的速度波动率,是高效可行的.

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.