EAAI Journal 2026 Journal Article
A novel interpretable dynamic weighted domain adaptation network for cross-domain fault diagnosis of bearings under time-varying speeds
- Xueyi Li
- Sixin Li
- Guangyao Zhang
- Yining Xie
- Tianyang Wang
- Fulei Chu
Significant progress has been made in rolling bearing fault diagnosis based on unsupervised domain adaptation (UDA). However, in complex operating conditions, especially under time-varying speed conditions, these methods still face critical challenges, including severe distribution discrepancies between source and target domains and limited interpretability of the diagnostic process. To address these issues, this paper proposes a novel interpretable dynamic weighted domain adaptation network (DWDAN), which combines a discrete wavelet-guided attention (DW-GA) layer with dynamic weighted joint domain adaptation (DWJDA) to achieve subdomain-level alignment while enhancing diagnostic interpretability. Specifically, the DW-GA layer incorporates physical prior knowledge to guide the model in extracting fault-related features in the wavelet domain, thereby improving the efficiency and effectiveness of feature learning under time-varying speed conditions. The DWJDA further performs a refined dynamic adjustment of marginal and conditional distribution alignment by jointly considering intra-class sample weighting and the relative importance of different distribution discrepancies, leading to enhanced domain adaptation capability. The comparative experiments are conducted on the datasets of Huazhong University of Science and Technology (HUST) and Northeast Forestry University (NEFU). The experimental results show that, compared with other mainstream methods, DWDAN exhibits significant advantages in cross-domain fault diagnosis tasks under time-varying speeds, achieving a maximum average diagnostic accuracy of 99. 08%. Further ablation experiments further verify the effectiveness of each key module in improving both diagnostic performance and interpretability, indicating that DWDAN has strong application potential for bearing fault diagnosis under time-varying speed.