基于NURBS曲线直接插补算法的嵌入式数控系统设计与实现

提出了一种结合486SX级别的X86微处理器和可编程逻辑器件CPLD两级控制的嵌入式数控系统设计方案,阐述了该系统的硬件接口电路设计;提出了基于改进S形加减速的NURBS曲线直接插补算法,在满足最大弦高误差、最大法向加速度以及最大进给速度要求的情况下,对插补曲线的加速段和减速段进行速度规划;最后采用基于该插补算法的嵌入式数控系统,在半圆形毛坯上进行了五角星NURBS曲线的实际加工,验证了所设计嵌入式数控系统的可行性和有效性,具有一定的工程应用价值。

Design and Implement of Embedded NC System Based on NURBS Direct Interpolation Algorithm

The design scheme of the embedded NC System, combined with X86 microprocessor of the 486SX level and complex programmable logic device CPLD, is proposed. The design of hardware interface circuits is elaborated and the NURBS direct interpolation algorithm based on improved S-shape acceleration and deceleration is presented. The speed is planned for acceleration and deceleration segments of the interpolation curve with the satisfaction of the chord height error, acceleration and jerk constraints. Finally, with the use of the embedded NC system based on the proposed interpolation algorithm, five-pointed star NURBS curves on the hemispherical work blank are processed practically. The results verify the feasibility and validity of this system. The NC system has the certain engineering application value.