Mission reliability modeling based on extended RQR chain considering process scheme robustness for multistate manufacturing systems

Process scheme robustness is the core of the “Method” in 5M1E (Man, Machine, Material, Method, Measurement, and Environment), which is the foundation of manufacturing quality and reliability assurance. However, previous studies frequently overlooked the significant impact of the coupling between the process scheme and process parameter robustness on the formation and degradation of mission reliability. Therefore, a novel method for modeling mission reliability in a multistate manufacturing system is proposed. This method is based on an extended RQR chain (manufacturing system Reliability, operational process Quality, and the produced product Reliability) while considering process scheme robustness. First, the connotation of process scheme robustness and mission reliability in multistate manufacturing systems is described. Second, an extended RQR chain (ERQR chain) model is established, which considers the influence of process scheme robustness on the high-quality operation of the manufacturing system. Third, based on the established ERQR chain model, an integrated mission reliability model considering process scheme robustness for multistate manufacturing systems is established. Specifically, the process scheme robustness is evaluated from three perspectives: manufacturing cost, operation time, and product qualification rate. Finally, a hydraulic pump is used as an example to verify the effectiveness of the proposed approach.