自动化车床管理问题的优化模型

Problem of automatic lathe management

以单位预防性换刀周期 (tp )内单位零件上的平均费用作为目标函数 ,建立了两个关于自动化车床管理的检查间隔及刀具更换策略的随机优化模型 .对题给数据统计分析后得出刀具寿命服从正态分布 ,采用离散递推的方法求出一个 tp 内的期望故障次数 ;用 MATLAB软件编程 ,在不同 tp下对不同检查周期 (tc)进行穷举和比较 ,找出使目标值最小的 tp 及 tc值 .针对题给的费用的多样性问题 ,在上述模型 的基础上进一步假设 ,建立了两个过渡模型作为费用多样性问题的两种特殊情况 ,然后建立了模型 .针对定期检查周期的缺点 ,提出了等概率 (故障 )周期检查方式 ,以获得更高的经济效益 .文中还利用随机模拟对模型 的合理性与较优性进行了定量检验 。

Two random optimal models are established for determining examining interval and replacement tactics of cutting tools on automatic lathe,whose objective are to minimize the average cost of a single part within a precautionary replacement interval (t p ) .In term of statistical analysis of given data,the life span distribution function of the cutting tools is accorded with the approximate normal distribution.Then,with discontinue recurrent method,expect the number of cutting tools breakdown in a precautionary replacement interval are attained.By means of enumeration and comparison method with Matlab software,the optimum checking interval and the optimum replacement interval for cutting tools are gained,which could minimize the average cost of a single part.Due to the variety of the cost concerned,based on model Ⅰ,transitional mode Ⅰ and transitional model Ⅱ are establilshed with more assumption,in fact,which are models under special situation.With the help of those two models,model Ⅱ is established.Due to shortcoming of equal checking method,an equal probability method is offered for more profits.By means of random stimulation ,the qualitative analysis is made to model Ⅰ as for its rationality and advantage,then,the quantitative analysis to the other models.