Quality Diagnosis for Rocket Body Structure Manufacturing Process Based on Product Quality <scp>DNA</scp>

ABSTRACT In the current multivariety and small‐batch production mode, it is difficult to fully reflect the evolution law of the sampling population due to incomplete sample information in the manufacturing of the rocket body structure. By referring to the principle of biological DNA, a knowledge‐based quality diagnosis strategy is adopted, and a quality diagnosis method for the rocket body structure manufacturing process based on product quality DNA is proposed in this paper. The accumulated experience or knowledge in the past is stored in the product quality DNA knowledge base in the form of cases. Through knowledge retrieval, historical cases with the highest similarity to the product quality DNA to be diagnosed are found, and reasonable control and rectification schemes are provided for the quality problems in the production process, so as to avoid the same quality problems in the future. The feasibility of the method is verified by two case studies of two welds. The results show that the method can effectively and accurately diagnose weld quality.