多台数控机床的时间截尾可靠性评估

王智明¹, 杨建国¹, 王国强², 张根保²

1.上海交通大学机械与动力工程学院;2.重庆大学机械工程学院先进制造技术实验室



摘要:

为了评估数控(NC)机床的可靠性,提出了用AIC、BIC信息准则选择多台NC机床故障间隔时间的分布模型和模型参数的方法.用Fisher信息矩阵法(FM)给出了模型参数和机床平均寿命的可靠度及可靠度为90%时的工作保证时间的区间估计,用Monte Carlo(MC)仿真法扩大少样本数据的样本容量,提高了区间估计的精度.结果表明,平均寿命的可靠度及可靠度为90%时的工作保证时间的区间估计长度分别减少了93%、95%.

关键词:  多台数控机床  时间截尾  可靠性评估  信息准则  置信区间

DOI：10.11918/j.issn.0367-6234.2011.03.018

分类号:O213.2

基金项目:高等学校全国优秀博士学位论文作者专项资金资助项目(200131);“高档数控机床与基础制造装备”科技重大专项资助项目(2009ZX04014-016)



Reliability evaluation of multiple NC machine tools with time truncation

WANG Zhi-ming¹, YANG Jian-guo¹, WANG Guo-qiang², ZHANG Gen-bao²

1.School of Mechanical Engineering,Shanghai Jiaotong University,200240 Shanghai,China;2.Advanced Manufacturing Technology laboratory,College of Mechanical Engineering,Chongqing University,400030 Chongqing,China)

Abstract:

To evaluate the reliability of NC machine tools,based on AIC and BIC information criteria,a method of model selection and parameter estimation for time-between-failures of multiple NC machine tools with time truncation is proposed.The confidence intervals of model parameters,the reliability given MTBF(mean time between failures) and the warranty time with 90% reliability are all given by Fisher Information Matrix method.At last,Monte Carlo simulation method is used to enlarge sample size of small-sample data to improve the precision of interval estimation.The results show that the interval length of reliability given MTBF and warranty time with 90% reliability are both reduce by 95% and 93% respectively.

Key words:  multi-NC machine tools  time truncation  reliability evaluation  information criterion  confidence interval  Monte Carlo(MC)