基于蒙特卡洛模拟的机床关键几何误差溯源方法  

Tracing Method for Key Geometric Errors of a Machine Tool Based on Monte Carlo Simulation

作　　者：唐宇航[1] 范晋伟[1] 陈东菊[1] 袁帅[1] 

机构地区：[1]北京工业大学机械工程与应用电子技术学院,北京100124

出　　处：《北京工业大学学报》2017年第11期1619-1628,共10页Journal of Beijing University of Technology

基　　金：国家自然科学基金资助项目(51275014);国家科技重大专项资助项目(2013ZX04011013)

摘　　要：为了溯源对加工误差影响最大的机床几何误差,提出了一种基于蒙特卡洛模拟的灵敏度分析方法.运用多体系统理论建立五坐标龙门加工中心加工误差生成模型,并建立了S形样件的直纹面数学模型.推导刀具轨迹到切削点的映射关系,建立了切削曲面模型.根据蒙特卡洛模拟采样机理,对机床加工误差模型进行全局灵敏度分析,获得影响机床加工误差的关键几何误差参数.按照灵敏度分析结果排序,获得影响z向加工误差最大的5项几何误差参数为δ_z(x)、δ_z(y)、δ_z(z)、δ_z(c)、δ_z(b).实验结果表明:5项关键误差参数共同作用对分析区域平均z向加工误差的影响度达88.2%,5项误差参数对机床z向加工误差影响最大,可以为提高五坐标机床的加工精度和设计精度提供指导.This paper presented a sensitivity analysis method for tracing the volumetric errors of a machine tool that made the greatest impact on machining errors based on Monte Carlo simulation theory.A machining error model of the five-axis gantry machine was established by means of a multi-body system theory and a mathematical model of S-shaped test piece was also established. The mapping relationship between the cutting points and tool paths was deduced. The mathematical model of cutting surface was then found. According to the principle of Monte Carlo simulation, a global sensitivity analysis was performed on the machining error model. Then,the geometric error parameters that make a great impact on machining errors were obtained. By sorting the sensitivity analysis results, five geometric errors 啄 z （ x）, δ2 （ y）,δ z （ z ）, δ z （ c ）,and δ2 （ b ） made the greatest influence on the machining error model of z- axis. Experimental results show that when working together with the machine,the five key error parameters make an average influence on z -axis machining error up to 88.2%. Thus, the five error parameters make a greatest influence on z -axis machining errors. This method can provide theoretical guidance for improving the machining precision and design precision of the five-axis machine tool.

关 键 词：误差溯源 全局灵敏度 蒙特卡洛模拟 S形样件 

分 类 号：TH161.5[机械工程—机械制造及自动化]