Multi-Modal Sensor Fusion — Temperature, Gas, Smoke as One Decision

A single-modality detector has a single failure mode that can take the layer offline. A thermal grid alone is degraded by occlusion. A gas mesh alone is degraded by ventilation. A camera alone is degraded by smoke obscuration. Fusion is not a marketing claim — it is the answer to the question "what happens when one layer is wrong?"

What fusion looks like

Each modality runs independently with its own anomaly detector. A fusion stage aggregates the signals with weights that reflect each sensor's confidence at that moment, and produces a single trust state — green, amber, red. The fusion logic is rule-based, not learned, because the decision has to be auditable.

Why rules, not models, for the trust state

• Auditable behaviour under class-society scrutiny.
• Predictable response when one sensor is in known failure (e.g. occluded camera).
• Inspectable test methodology against fixed event catalogue.

The weighting scheme

• Per-vehicle thermal grid: highest weight when ambient is stable, lower under solar gain.
• Gas sensing: highest weight in sealed compartments and low-ventilation states.
• Video analytics: highest weight on access lanes and ramps.
• Fiber-optic LHD: highest weight on weather decks and open spaces.