Anomaly detection in injection-molded products under data imbalance and fuzzy boundaries
摘要
Data-driven classification techniques exhibit notable advantages in the quality inspection of plastic products but face challenges such as data imbalance and unclear category boundaries. To address these issues, this paper proposed a semi-supervised method that uses a dual-model structure, leveraging abundant qualified samples to reduce reliance on defective samples. Specifically, qualified samples were divided into two categories based on size distribution, and sub-models based on variational autoencoder and Wasserstein generative adversarial network were trained separately. The outputs were then integrated using weighted aggregation for final classification. Experimental results demonstrated that the dual-model structure improved classification accuracy on the test set by 4.5 % and 6 % compared with single-model structures and by more than 5.3 % compared with the supervised learning approach.