Predictive Maintenance (PdM) is the application of ML to equipment sensor data to detect anomalies before failure — replacing scheduled maintenance (wasteful) and reactive repair (costly). The core loop is: collect sensor signals → build health baseline → detect deviation → predict RUL → trigger intervention.
For HVAC systems like Carrier's, sensors measure temperature, pressure, power draw, vibration, and refrigerant flow. A fleet of 10,000+ units becomes a training corpus. The ML challenge is heterogeneity: equipment age, model variants, install environments. The architectural challenge is scale: streaming ingest, unified feature store, single model generalizing across all variants.
Carrier's actual implementation: AWS Glue + SageMaker. Raw IoT data → S3 lake → Glue ETL → SageMaker training on historical fault labels → real-time inference → Abound platform alerts.
John's QA background maps directly here:
| Term | Definition |
|---|---|
| Remaining Useful Life (RUL) | Predicted time until equipment failure. The primary output of many PdM models. |
| Health Index | A normalized 0–1 score representing equipment condition. Aggregates multiple sensor signals. |
| FMEA | Failure Mode & Effects Analysis — systematic mapping of failure modes to causes. Informs feature selection. |
| Condition Monitoring | Continuous sensor data collection to track equipment state over time. |
| Anomaly Detection | Unsupervised ML approach: learn normal operating envelope, flag deviations. First layer before supervised fault classification. |
| Digital Twin | A virtual replica of physical equipment, fed by real sensor data, used for simulation and what-if analysis. |
| Feature Store | Centralized repository of engineered features (time-window aggregations, ratios) for consistent model training and inference. |
| Drift Detection | Detecting when model performance degrades because equipment characteristics or operating conditions have shifted. |
| OEE | Overall Equipment Effectiveness — the standard manufacturing KPI combining availability, performance, quality. |
What it is: Predicting future demand for products/parts to optimize inventory, production schedules, and supply chain capacity. For Carrier: predicting HVAC unit sales by region/season, spare parts demand, service call volume.
Architectural pattern: Time-series ML (ARIMA/Prophet for baselines; gradient boosting or LSTM for complex patterns) fed by historical sales, weather data, economic signals. Feature engineering is the critical work — holiday effects, weather correlations, supply disruption signals.
John's bridge: Cardinal Health — SAP-based order fulfillment and distribution analytics for 80+ radiopharmacies. Same problem: forecast radiopharmaceutical demand by imaging center, by isotope half-life window (2-hour delivery). The precision requirement (radioactive decay) is actually harder than HVAC.
| Layer | AWS Service | Role in PdM |
|---|---|---|
| Ingest | IoT Core, Kinesis | Real-time sensor stream from equipment |
| Store | S3 Data Lake | Raw + processed sensor history |
| Transform | AWS Glue | ETL, feature engineering, time-window aggregation |
| Train | SageMaker | Model training, HPO, experiment tracking |
| Serve | SageMaker Endpoints | Real-time inference on new sensor readings |
| GenAI | Amazon Bedrock | Conversational AI ("Tell Me More" in Abound) |
| Orchestrate | Step Functions / Lambda | Pipeline automation, alerting workflows |