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2026-06-24data

A cross-process welding penetration status prediction algorithm based on unsupervised domain adaptation in laser and TIG welding

Sen Li, Haichao Cui, Chendong Shao, Yaqi Wang, Xinhua Tang

PDF preview for A cross-process welding penetration status prediction algorithm based on unsupervised domain adaptation in laser and TIG welding
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Key claim

Achieves over 80% accuracy in cross-process welding classification.

In plain English

Imagine you're working on a system that classifies the state of weld penetration in different welding processes. You might train a model on one type of welding, like TIG, but when you try to use it for another type, like laser welding, it often fails because the physical mechanisms are so different. This is a common problem known as domain shift, where a model trained in one context doesn't perform well in another. It can lead to inaccurate classifications and wasted resources, which is frustrating for builders trying to implement reliable systems across various welding techniques.

Currently, many people rely on supervised learning, where models are trained on labeled data from a specific process. However, this approach breaks down when you need to transfer knowledge to a different process. The model struggles to adapt because it hasn't learned the relevant features for the new context. This is what's called domain shift, and it can result in poor performance and high relabeling costs when trying to adapt to new processes.

To address this, the authors propose a new approach that uses unsupervised domain adaptation (UDA) combined with a gradual source domain expansion (GSDE) strategy. The idea is to allow the model to learn from both the original and new domains without needing extensive labeled data for the new process. By gradually expanding the source domain, the model can better capture the differences and similarities between the welding processes, leading to improved accuracy.

In practical terms, this method allows builders to deploy models that can effectively monitor and classify weld penetration across different welding systems without the need for extensive retraining or relabeling. The results show that the proposed method achieves over 80% accuracy in cross-process scenarios, which is a significant improvement over traditional supervised methods, making it a valuable tool for those working in welding applications.

Novelty
7.5/10

The proposed unsupervised domain adaptation framework introduces a new strategy for handling domain shifts in welding processes.

Reliability
8.0/10

The results are supported by strong experimental validation across multiple datasets with significant improvements over baselines.

Deep reliability assessment

The methodology supports that GSDE improves accuracy and stability over several UDA baselines on the authors' TIGFH and LSPS transfer splits, with five random seeds and both same-process and cross-process experiments. The broader claim of industrial versatility is less supported because the paper does not appear to test deployment-time drift, unseen factories/sensors/materials, label shift, calibration, or real closed-loop welding control.

Reproducibility

No public code repository is mentioned in the provided abstract, introduction, results, limitations/discussion, or conclusion. The paper uses dedicated TIGFH and LSPS welding datasets, but no public dataset link or release information is visible in the provided text.

Key figure

The key architecture is a ResNet-50-based unsupervised domain adaptation pipeline where adversarial, semantic, and semi-supervised losses align source and target features while GSDE progressively promotes high-confidence pseudo-labeled target samples into an expanded source domain.

Benchmark results

TIGFHaverage accuracy: 90.65vs FixBi+4.24 percentage pointsSOTA
LSPSaverage accuracy: 90.72vs FixBi+3.79 percentage pointsSOTA
~TIGFH→LSPSaccuracy: 80.48vs supervised baseline+43.39 percentage pointsSOTA
~LSPS→TIGFHaccuracy: 81.13vs supervised baseline+43.40 percentage pointsSOTA