Deep Generative Models in Condition and Structural Health Monitoring: Opportunities, Limitations and Future Outlook

TL;DR

This paper reviews the use of deep generative models in condition and structural health monitoring, highlighting their potential to improve data synthesis, domain adaptation, and fault detection amid challenges like data scarcity and complexity.

Contribution

It systematically analyzes recent DGM applications in CM/SHM, compares them with traditional methods, and discusses future research directions and limitations.

Findings

DGMs enhance data generation and fault diagnosis in SHM.

DGMs face challenges in explainability and computational efficiency.

Future directions include zero-shot learning and hybrid models.

Abstract

Condition and structural health monitoring (CM/SHM) is a pivotal component of predictive maintenance (PdM) strategies across diverse industrial sectors, including mechanical rotating machinery, aircraft structures, wind turbines, and civil infrastructures. Conventional deep learning models, while effective for fault diagnosis and anomaly detection through automatic feature learning from sensor data, often struggle with operational variability, imbalanced or scarce fault datasets, and multimodal sensory data from complex systems. Deep generative models (DGMs) including deep autoregressive models, variational autoencoders, generative adversarial networks, diffusion-based models, and emerging large language models, offer transformative capabilities by synthesizing high-fidelity data samples, reconstructing latent system states, and modeling complex multimodal data streams. This review systematically examines state-of-the-art DGM applications in CM/SHM across the four main industrial systems mentioned above, emphasizing their roles in addressing key challenges: data generation, domain adaptation and generalization, multimodal data fusion, and downstream fault diagnosis and anomaly detection tasks, with rigorous comparison among signal processing, conventional machine learning or deep learning models, and DGMs. Lastly, we discuss current limitations of DGMs, including challenges of explainable and trustworthy models, computational inefficiencies for edge deployment, and the need for parameter-efficient fine-tuning strategies. Future research directions can focus on zero-shot and few-shot learning, robust multimodal data generation, hybrid architectures integrating DGMs with physics knowledge, and reinforcement learning with DGMs to enhance robustness and accuracy in industrial scenarios.