Considering non-equivalence of parameter domain of spline and time domain, which, in continuous micro line spline reconstruction manufacturing, causes low computational speed of interpolation by interpolation with non-recursion, or great change of knot velocity and low accuracy of knot position by direct recursion interpolation with equal increment of parameter. Theories which includes parameter domain transformation method that associated parameter domain with number of interpolation period is presented, the quintic spline based on the new domain is built. Tangent vector and second derivative vector of knot pre-computation with flexible acceleration and deceleration(acc/dec) and fast recursive interpolation of reconstruction quintic spline are presented for micro line machining. The simulation and the experiment using new theories in micro line machining show that machining efficiency is increased by 3.3 times and time of recursive interpolation is about one third of the time of interpolation by curve formula. The result indicates that computational speed of interpolation is improved by spline reconstruction and fast recursion, the situation of frequent acc/dec in micro line machining is reduced by velocity planning based on the new spline, meantime, machining accuracy can be ensured, machining efficiency is raised, so performance of CNC is promoted.%针对样条曲线参数域与时间域不一致,导致在数控系统的连续微段加工中,重构样条曲线无法快速递推插补,计算效率低；而直接等参数增量递推,又会带来节点速度突变、位置精度差的问题.故提出了实现参数域和插补周期数统一的域变换算法,建立了新参数域下的五次样条曲线,并且给出了基于该曲线的柔性加减速条件下节点切矢量及二阶导矢预计算,及曲线快速递推的算法.应用新算法的微段加工实验表明,加工效率提高了约3.3倍,而递推插补运算时间的减少到直接利用曲线公式插补的1/3.因此算法通过新型样条重构及快速递推提高了插补计算的速度,同时,在保证精度的条件下,基于新样条的速度规划减少了微段加工频繁加减速,提高了加工效率,提升了数控系统的性能.
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