一种优化的数据采样法在开环数控系统中的应用

摘要

Sampled-data interpolation algorithm applied to open-loop CNC （computer numerical control） has a problem of odd distance, which affects the machining system accuracy. In this paper, the causes and effects of odd distance are analyzed, and an optimized sampled-data interpolation algorithm is proposed. Odd distance is distribu- ted into each interpolation cycle to compensate odd distance quickly. In addition, the speed of the optimized sam- pied-data interpolation algorithm is fast, and trajectory traeking error is less than the equivalent of a pulse. In order to evaluate the effect, the comparison of the traditional and optimized interpolation algorithm has been done through programming and experiment. The result shows that optimized interpolation can effectively solve the problem of low accuracy caused by odd distance through compensatory odd distanee output, and thus greatly enhance the system accuracy.%数据采样法运用于开环数控系统会产生零头距离问题，并且影响系统的加工精度。对零头距离产生的原因及影响进行研究与分析，提出一种优化数据采样法，采用将零头距离分配到各插补周期的方式补偿输出零头距离。这种方式较快地补偿了零头距离，插补速度较快，轨迹的跟踪误差小于一个脉冲当量。并通过编写插补程序和实验，对传统数据采样法与优化算法进行测试比较。优化算法通过对零头距离进行补偿输出，有效地解决了由零头距离引起的系统加工精度不足的问题，大大提高了系统精度。