基于EEMD与曲面重构的自由曲面加工误差分解与补偿  

Machining Error Decomposition and Compensation of Free-form Surface Based on EEMD and Surface Reconstruction

作　　者：王俊超 陈岳坪[1] 李杰[1] Wang Junchao;Chen Yueping;Li Jie(School of Mechanical and Automotive Engineering,Guangxi University of Science and Technology,Liuzhou,Guangxi 545616,China;不详)

机构地区：[1]广西科技大学机械与汽车工程学院

出　　处：《工具技术》2024年第7期142-147,共6页Tool Engineering

基　　金：国家自然科学基金(51565006,52165054);广西自然科学基金(2020GXNSFAA159142,2018GXNSFAA050085);广西高校高水平创新团队及卓越学者计划资助项目(桂教人[2016]42号);广西科技大学创新团队支持计划项目(科大科研发[2017]64号)。

摘　　要：为了减小自由曲面零件的加工误差和提高加工精度,提出了集合经验模态分解(Ensemble Empirical Mode Decomposition, EEMD)与曲面重构结合对加工误差进行分解和补偿的方法。利用EEMD对在机检测得到的第一次切削加工后的加工误差进行分解,得到若干固有模态函数(Intrinsic Mode Functions, IMFs);根据系统误差特征,通过设置相关系数阈值筛选出加工误差中含有系统误差的IMFs分量(即分解出的系统误差);根据该系统误差,利用曲面重构法得到新的加工曲面,并生成新的NC代码,再次进行切削加工,对系统误差进行补偿。通过EEMD加工误差分解仿真分析可以得出,EEMD具有较为理想的加工误差分解能力。自由曲面零件加工实例结果显示,采用本文提出的方法对加工误差进行补偿后的最大绝对加工误差由0.0632mm降为0.0139mm,平均绝对加工误差由0.0491mm降为0.0052mm,加工精度提高了89.4%,证明了该方法在自由曲面零件加工误差补偿方面的有效性。In order to reduce the machining errors of free-form surface parts and improve the machining accuracy,an Ensemble Empirical Mode Decomposition(EEMD)method combined with surface reconstruction is proposed to decompose and compensate the machining errors.EEMD is used to decompose the machining errors after the first cutting detected by the machine,and several Intrinsic Mode Functions(IMFs)are obtained.According to the characteristics of systematic errors,the IMFs component containing systematic errors in machining errors is screened by setting the threshold of correlation coefficient,that is,the decomposed systematic errors.According to the system error,a new machining surface is obtained by surface reconstruction method,and a new NC code is generated according to it,and the machining is carried out again to compensate the system error.Through the simulation analysis of EEMD decomposition machining error,it can be concluded that EEMD has a relatively ideal machining error decomposition ability.The machining example results show that the maximum absolute machining error decreases from 0.0632mm to 0.0139mm and the average absolute machining error decreases from 0.0491mm to 0.0052mm when the machining error is compensated by the method proposed in this paper.The machining accuracy is increased by 89.4%.The effectiveness of this method in machining error compensation of free-form surface parts is proved.

关 键 词：集合经验模态分解 加工误差分解 系统误差 曲面重构 误差补偿 

分 类 号：TG659[金属学及工艺—金属切削加工及机床] TH161[机械工程—机械制造及自动化]