đ€ AI Summary
In digital twinâbased fault diagnosis, performance degradation arises from distributional shift (sim-to-real gap) between simulation and real-world data. To address this, this paper proposes a domain-adversarial neural network (DANN)âbased cross-domain diagnosis frameworkâthe first application of DANN to digital twinâdriven fault diagnosis. The framework features a lightweight, embeddable architecture compatible with mainstream time-series models, including CNN, TCN, Transformer, and LSTM. Evaluated on a robotic fault dataset, the DANN-enhanced CNN improves real-world diagnostic accuracy from 70.00% to 80.22%, outperforming all baseline methods. This work effectively mitigates domain shift and establishes a novel paradigm for reliable transfer of simulation-derived knowledge to physical systems within digital twin frameworks.
đ Abstract
Digital twins offer a promising solution to the lack of sufficient labeled data in deep learning-based fault diagnosis by generating simulated data for model training. However, discrepancies between simulation and real-world systems can lead to a significant drop in performance when models are applied in real scenarios. To address this issue, we propose a fault diagnosis framework based on Domain-Adversarial Neural Networks (DANN), which enables knowledge transfer from simulated (source domain) to real-world (target domain) data. We evaluate the proposed framework using a publicly available robotics fault diagnosis dataset, which includes 3,600 sequences generated by a digital twin model and 90 real sequences collected from physical systems. The DANN method is compared with commonly used lightweight deep learning models such as CNN, TCN, Transformer, and LSTM. Experimental results show that incorporating domain adaptation significantly improves the diagnostic performance. For example, applying DANN to a baseline CNN model improves its accuracy from 70.00% to 80.22% on real-world test data, demonstrating the effectiveness of domain adaptation in bridging the sim-to-real gap.