A Sustainable Anomaly Detection Framework for Autonomous Surface Ship: Adaptive Subsystem-Level Anomaly Detection Algorithm via MLOps

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Published Jul 3, 2026
Minji KIM Gwangho YUN Hwasup JANG Jaecheul PARK

Abstract

For the stable operation of Maritime Autonomous Surface Ships (MASS), this study proposes a sustainable anomaly detection framework that integrates a subsystem-level Condition-Based Maintenance (CBM) model with an adaptive MLOps pipeline. The main engine is decomposed into 14 functional units, each monitored by a hybrid algorithm that combines an Attention-LSTM-AutoEncoder and an Isolation Forest to detect subtle anomalies. To address model performance degradation caused by gradual data drift in maritime environments, an Autonomous Maintenance Mechanism is developed. This mechanism utilizes state severity (Z-Score) and drift velocity (ΔZ) indicators to algorithmically distinguish between sudden physical faults and gradual sensor drift. Based on this distinction, the MLOps pipeline accumulates confirmed drift in a buffer and selectively retrains and redeploys models using local onboard data once sufficient evidence has been gathered, while bypassing suspected fault conditions to avoid learning anomalous patterns. Experiments on an engine testbed indicate that the proposed system can suppress the Anomaly Rate (AR_t) during data drift and help restore diagnostic reliability, suggesting a practical basis toward self-sustaining condition monitoring for MASS.

How to Cite

KIM, M., YUN, G., JANG, H., & PARK, J. (2026). A Sustainable Anomaly Detection Framework for Autonomous Surface Ship: Adaptive Subsystem-Level Anomaly Detection Algorithm via MLOps. PHM Society European Conference, 9(1), 1–11. https://doi.org/10.36001/phme.2026.v9i1.4927
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Keywords

MLOps, Sustainable, Data Drift, New Normal, Attention-LSTM-AE

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Section
Technical Papers