Refining operation guidelines with model-checking-aided FRAM to improve manufacturing processes: a case study for aeroengine blade forging

With the aid of the Finite State Machine (FSM) and formal verification, a framework of updated Functional Resonance Analysis Method (FRAM) is proposed to refine operation guidelines as such and hence improves manufacturing processes by reducing risks of unqualified products during manufacturing operations. Firstly, the FRAM is used to model a manufacturing process in terms of the corresponding guideline, taking into account all the basic activities each with their performance variability and the potential couplings among the activities. Secondly, based on the FRAM model further interpreted with FSM, the model checker SPIN is adopted to achieve the exhaustive search (in the sense of execution) for the paths leading to manufacturing risks, which supports to illustrate how the performance variability in the activities couples and finally causes violation of quality control requirements. Finally, possible inadequacies and deficiencies of the operations are identified and measures for refining the guideline are developed to minimize the risks due to the inherent issues of specification in the guideline. In a case study, the proposed framework is applied to a typical manufacturing process prone to risks, i.e., forging of aeroengine titanium alloy blades, and the analysis results indicate practicality of the framework, as well as effectiveness of the guideline refinements.