Engine Health State Index (EHSI)
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Abstract
Assessing the health of diesel engines is challenging due to multiple coexisting failure modes, overlapping fault signatures, and highly imbalanced operational data. This paper proposes an Engine Health State Index (EHSI), a probabilistic health metric that aggregates risk estimates from multiple failure-code–specific models.
The framework employs a collection of binary classifiers, each trained to estimate the likelihood of a specific failure code from historical telemetry and diagnostic data. At each time step, the resulting failure risk vector provides a distributed representation of latent fault exposure rather than a single dominant failure mode. EHSI maps this risk distribution to a scalar health index using normalized uncertainty measures, enabling continuous tracking of health degradation without relying on explicit fault triggers.
Experiments on real-world diesel engine datasets show that EHSI produces smooth and interpretable health trajectories that correlate with impending failures while remaining sensitive to early-stage degradation. The proposed approach is model-agnostic, extensible to additional failure modes, and suitable for large-scale fleet monitoring applications.
How to Cite
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Remaining Useful Life, Prognostics, Predictive Maintenance, Engine Health Monitoring, Downtime reduction
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