为实现对NURBS曲线的高速高精度加工,基于同周期控制思想,提出了一种同周期控制NURBS曲线插补算法(即数控系统的插补周期与伺服系统的控制周期同步)。通过软件系统的模块化设计,将费时、复杂的运算经过合理设计安排到预处理模块;同时,为进一步提高算法运算速度和指令高速传输,在算法处理方面采用计算简单并能确保速度曲线平滑的移动平均加减速控制算法对曲线进行加减速处理;在硬件通讯方面采用双端口RAM作为传输接口。最后搭建系统实验平台并对同周期控制NURBS曲线高速高精度插补算法进行实验研究。实验结果表明同周期控制NURBS曲线插补算法可以实现高速高精度加工的插补控制。
In order to realize high-speed and high-precision machining for NURBS curve,an interpolation algorithm based on the thinking of the same cycle control,with which NURBS curve can be controlled with the same cycle between the NC interpolation cycle and the servo-system control cycle,is proposed.Depending on the modular design of the software system,the time-consuming and complex calculation can be reasonable design and placed in the pre-process module.Besides,in order to improve the operational speed of interpolation algorithm and the transfer speed of the instruction code further,on the aspect of algorithm processing,a novel moving average acceleration and deceleration control algorithm,characterized by simple calculation and ensuring the velocity curve smooth,is used to process the acceleration and deceleration curve.In addition,dual-port RAM is also used to communicate between different hardware.Finally,the experimental testing system is built and the proposed algorithm has been carried out.The experimental results verify that the same cycle control NURBS curve interpolation algorithm can achieve high-speed and high-precision processing interpolation control.