基于鲁棒参数控制方法的可变控制线控制图

Adaptive control chart with variable control lines based on robust parameter control methodology

针对在制造过程中应用鲁棒参数控制时,其过程均值和方差都会经常改变,且无法直接使用现有的控制图技术进行统计过程控制,提出了基于应用鲁棒参数控制的可变控制线控制图的设计方法。它不同于传统的适应性控制图设计方法,是该研究通过对过程均值和方差变化的有效估计,给出了可变控制线的调节律算法,为控制图自动跟踪过程变化提供了一种可行的方法。通过实例分析,验证了上述方法的有效性和实用性。

Currently, no existing Statistical Process Control （SPC） techniques could be directly used to monitor the Robust Parameter Control （RPC） application process in which changes in process mean and variance might occur frequently. An alternative design approach of adaptive control charts with variable control lines was presented directly based on RPC application process. This design strategy was quite different from the traditional adaptive control chart design approaches in adjusting variable control parameters via analyzing the location of latest sample points. A new optimization algorithm of variable control lines was designed by estimating the changes of process mean and variance. Through an effective online estimation of process mean and variance, a better performance-tracking on frequently changing process could be expected. A case study was presented to verify the effectiveness and feasibility of this proposed approach.