摘要
借助于函数性数据分析方法,提出了一种求解数控机床瞬时可用度方法。首先以四次Bernstein多项式为基函数对可靠度估计值进行平滑,并采用最小二乘法估计基函数拟合参数。其次,对维修度估计值按照故障发生时间截面进行跨截面套准,按维修度套准后的变化趋势,选择傅里叶基函数对其进行平滑处理,并采用非线性最小方差法求解拟合系数。最后,通过构建基于函数性线性回归模型建立了数控机床瞬时可用度模型,并以18台加工中心为实例进行分析。实例分析表明,该建模方法瞬时可用度拟合相关系数达到0.9641,能有效地对数控机床的瞬时可用度进行评估。
A new way to calculate the instantaneous availability of the computer numerical control（CNC） machine tool was proposed based on the functional data analysis method.Using the quartic Bernstein polynomial as basis function to smooth the reliability estimation values,as well as the least square method to estimate the fitting parameters of the basis function.The estimated maintainability was across-section adjusted according to the trouble occurrence time section.Based on the adjusted trend of maintainability,the Fourier basis function was chosen to smooth it.The fitting coefficients were solved by the non-linear least variance method.A model was built for the instantaneous availability of the CNC machine tool based on the functional linear regression model,and taking 18 machine centers as examples to verify the proposed model.The results showed that the proposed model gave out the correlation coefficient of 0.9641,being effective to evaluate the instantaneous availability of the CNC machine tool.
出处
《吉林大学学报（工学版）》
EI
CAS
CSCD
北大核心
2012年第5期1151-1156,共6页
Journal of Jilin University:Engineering and Technology Edition
基金
国家重大科技专项项目(2010ZX04014-011
2010ZX04014-016
2010ZX04015-011
2011ZX04014-011)
吉林大学科学前沿与交叉学科创新项目(200903171)
吉林大学研究生创新研究计划项目(20111057)
关键词
机床
数控机床
瞬时可用度
函数性数据分析
基函数
最小二乘法
machine tool
CNC machine tool
instantaneous availability
functional data analysis
basis function
least square method
