Architecture of cyberphysical systems for UAV-based late-fusion defect detection in photovoltaic modules

The subject of research is the architectural advancement of inspection systems for large-scale solar power plants. As global solar infrastructure expands, reliance on manual or offline analytical methods creates significant operational bottlenecks. The goal of research is to improve the operational utility of unmanned aerial vehicle (UAV)-based photovoltaic module inspection by developing a cyber-physical system (CPS) architecture. It integrates onboard deep learning, edge nodes, cloud analytics, and Supervisory Control and Data Acquisition (SCADA)-aware decision-making into a single coordinated workflow. The tasks of research: 1) formalise a multi-tiered CPS architecture (UAV-edge-cloud) and define interfaces for data, geo-tags, and alarms; 2) develop and validate an onboard thermographic detection pipeline with palette-aware fusion; and 3) integrate detection results with a SCADA-aware logic layer for hazard inference and fire risk mitigation. The methods of research: Computer vision and deep learning (YOLOv11) are used for onboard defect segmentation. Model ensembling via a late-fusion strategy for M2 and M3 thermal palettes mitigates domain shift. RTK-supported spatial clustering algorithms ensure precise geo-indexing and deduplication, and deterministic Boolean logic assesses fire risks based on bypass diode states. The results obtained with five-fold cross-validation shows the proposed architecture significantly outperforms single-modality baselines. The onboard YOLOv11 model achieved a macro mAP@0.5 of 0.91 and 0.90 for M2 and M3 palettes, respectively. The late-fusion ensemble elevated mAP@0.5 for cracks to 0.96 and delamination to 0.95. It reduced end-to-end per-frame processing latency from 4.235 s to 2.858 s. Field validation demonstrated an error of 0.71 defects per inspected string compared to manual counts. Sensitivity analysis highlighted that a 10 m flight altitude provides an optimal balance, yielding 93% precision and 90% recall. Conclusions: Treating UAV inspection as an integrated cyber-physical service improves defect detection. This offers a scalable, real-time solution for preventive maintenance and automated fire-risk mitigation in renewable energy.