Syn-Diag: An LLM-based Synergistic Framework for Generalizable Few-shot Fault Diagnosis on the Edge
Zijun Jia, Shuang Liang, Jinsong Yu
TL;DR
Syn-Diag addresses data scarcity and edge deployment constraints in industrial fault diagnosis by integrating cross-modal semantic alignment, content-aware synergistic reasoning with dynamic prompts, and cloud-edge knowledge distillation with online updating. The framework aligns time-frequency spectrogram features with LLM semantic space, enables a multiple-choice style inference, and distills knowledge to a lightweight edge model that can update the cloud model iteratively via a shared decision space. Across six datasets under 1-, 3-, 5-, 7-shot and cross-condition settings, Syn-Diag achieves state-of-the-art performance, while the edge model reduces size by $83\%$ and latency by $50\%$ relative to the cloud model. This work presents a practical, robust paradigm for scalable, adaptive intelligent diagnostics on resource-constrained devices.
Abstract
Industrial fault diagnosis faces the dual challenges of data scarcity and the difficulty of deploying large AI models in resource-constrained environments. This paper introduces Syn-Diag, a novel cloud-edge synergistic framework that leverages Large Language Models to overcome these limitations in few-shot fault diagnosis. Syn-Diag is built on a three-tiered mechanism: 1) Visual-Semantic Synergy, which aligns signal features with the LLM's semantic space through cross-modal pre-training; 2) Content-Aware Reasoning, which dynamically constructs contextual prompts to enhance diagnostic accuracy with limited samples; and 3) Cloud-Edge Synergy, which uses knowledge distillation to create a lightweight, efficient edge model capable of online updates via a shared decision space. Extensive experiments on six datasets covering different CWRU and SEU working conditions show that Syn-Diag significantly outperforms existing methods, especially in 1-shot and cross-condition scenarios. The edge model achieves performance comparable to the cloud version while reducing model size by 83% and latency by 50%, offering a practical, robust, and deployable paradigm for modern intelligent diagnostics.
