基于Copula函数的切削力与表面粗糙度的相关性  

Correlation between cutting force and surface roughness based on Copula function

作　　者：裴宏杰[1] 李公安 付坤鹏 陈少峰[1] 王贵成[1] PEI Hongjie;LI Gong-an;FU Kunpeng;CHEN Shaofeng;WANG Guicheng(School of Mechanical Engineering,Jiangsu University,Zhenjiang,Jiangsu 212013,China)

机构地区：[1]江苏大学机械工程学院,江苏镇江212013

出　　处：《江苏大学学报（自然科学版）》2018年第2期174-178,共5页Journal of Jiangsu University：Natural Science Edition

基　　金：国家科技重大专项(2013ZX04009031-4);江苏省科技创新基金资助项目(BC2014202);江苏省普通高校研究生科研创新计划项目(CXZZ12-0658)

摘　　要：为了实现自动化切削加工中表面粗糙度的预测,需要定量描述常用监测参数切削力和表面粗糙度之间的非线性关系,提出了基于Copula函数的相关性研究方法.以车削7075高强度铝合金为试验对象,采用控制变量法得到切削力和表面粗糙度值,然后建立它们各自的边缘分布函数,并利用优化的Copula函数构建多变量联合分布函数,最后基于Copula函数理论以及联合函数模型分析了切削力和表面粗糙度整体和尾部相关关系.结果表明:切削力和表面粗糙度整体上有着明显的正相关关系,且相关结构中心对称,同时尾部相关系数趋向于0,即尾部相关程度较小.To predict the surface roughness in machining process,the nonlinear correlation between common monitoring parameters of cutting force and surface roughness should be quantitatively described.The sample values of cutting force and the surface roughness were obtained by turning 7075 high strength aluminum alloy by control variable method.The marginal distribution functions were established,and the multivariate joint distribution function was constructed by the optimized Copula function.Based on the Copula function theory and the joint function model,the global,local and tail relationship between cutting force and surface roughness was analyzed.The results show that the cutting force has obviously positive correlation with surface roughness.The correlation structure is centrosymmetric,and the correlation degrees at the both ends are larger than that at the center.The tail correlation coefficient tends to zero,which illuminates that the tail correlation degree is small.

关 键 词：COPULA函数 切削力 表面粗糙度 联合分布函数 相关性分析 

分 类 号：TH16[机械工程—机械制造及自动化]