慢刀伺服车削刀具补偿算法优化  

Optimization of Tool Compensation Algorithm for Slow Tool Servo Turning

作　　者：郭航言 康敏[1,2] 周玮 GUO Hang-yan;KANG Min;ZHOU Wei(College of Engineering,Nanjing Agricultural University,Nanjing 210031,China;Key Laboratory of Intelligence Agricultural Equipment of Jiangsu Province,Nanjing 210031,China)

机构地区：[1]南京农业大学工学院,南京210031 [2]江苏省智能化农业装备重点实验室,南京210031

出　　处：《表面技术》2022年第4期308-316,383,共10页Surface Technology

基　　金：2019江苏省现代农机装备与技术示范推广项目(6026A9)。

摘　　要：目的优化刀具补偿算法,从而提高复杂曲面慢刀伺服车削加工的表面质量。方法针对法向补偿算法容易导致X轴动态性能降低以及Z向补偿算法存在较大插值误差等问题,提出了一种基于坐标变换的几何补偿算法。通过坐标变换提高求解精度并简化算法,利用几何变换关系将X轴的补偿分量集中于Z轴,保证X轴的动态性能,并降低插值误差。以环曲面为例,对刀具补偿算法进行仿真分析和试验验证。结果仿真结果显示,在法向补偿算法下X轴速度波动较大,而在本文提出的算法下X轴可以保持匀速运动;在刀具补偿环节,与本文提出的算法相比,Z向补偿算法产生的插值误差较大,最大插值误差达到了0.015 mm以上。试验结果显示,在法向补偿算法下环曲面的表面粗糙度值最大(Ra=0.112μm),且远大于Z向补偿算法和本文提出的算法;而在Z向补偿算法和本文提出的算法下,环曲面的表面粗糙度值相差不大(分别是Ra=0.066μm和Ra=0.062μm)。在法向补偿算法、Z向补偿算法和本文提出的算法下得到的PV值分别为16.9、13.8、8.8μm。结论在保证X轴动态性能的前提下,刀具补偿算法对表面粗糙度影响不大。与法向补偿算法和Z向补偿算法相比,本文提出的算法将环曲面面型精度分别提高了92.0%和56.8%,说明本文提出的刀具补偿算法可以提高表面加工质量。In order to improve the surface quality of complex surface in slow tool servo turning,the tool compensation algorithm was optimized.In view of the problems that normal compensation algorithm can easily lead to the decrease of the dynamic performance of X-axis and large interpolation error in Z-direction compensation algorithm,a geometric compensation algorithm based on coordinate transformation was proposed in this paper.Coordinate transformation can improve the accuracy of the solution and simplify the algorithm.By using the geometric transformation relationship,the compensation component of X-axis could be concentrated on the Z-axis,which not only ensured the dynamic performance of X-axis,but also reduced the interpolation error.Taking the toric surface as an example,the tool compensation algorithm proposed in this paper was simulated and verified by experiments.The simulation results showed that the velocity of X-axis fluctuates greatly under the normal compensation algorithm,while the X-axis can keep uniform motion under the algorithm proposed in this paper.In the tool compensation link,compared with the algorithm proposed in this paper,the interpolation error under Z-direction compensation algorithm was larger,and the maximum interpolation error was more than 0.015 mm.The experimental results showed that the value of surface roughness of the toric surface was the largest under the normal compensation algorithm(Ra=0.112μm),which was much larger than that under the Z-direction compensation algorithm and the algorithm proposed in this paper.However,under the Z-direction compensation algorithm and the algorithm proposed in this paper,the value of surface roughness of the toric surface was similar(Ra=0.066μm and Ra=0.062μm respectively),which indicates that the tool compensation algorithm has little effect on the surface roughness on the premise of ensuring the dynamic performance of X-axis.The values of PV obtained under the normal compensation algorithm,the Z-direction compensation algorithm and the algorith

关 键 词：慢刀伺服 刀具路径 坐标变换 几何补偿 表面粗糙度 面型精度 

分 类 号：TG506[金属学及工艺—金属切削加工及机床]