SensingAlgorithms

Per-Vehicle Thermal Baselines and 6 °C Anomaly Detection

By Engineering — Sensing · March 28, 2026 · 8 min read

A deck-wide threshold misses the early-stage signature. A per-vehicle rolling baseline catches it 18–25 minutes earlier in our bench tests.

Static thresholds are simple and almost useless on cargo decks. Engine bays cool at different rates. Hot ambient sailings push background temperatures up. A fixed 70 °C trip line either fires constantly or never fires until it is too late.

Rolling per-vehicle baseline

Each sensor cell maintains a rolling EWMA of the surface temperature for the vehicle within its field of view. The trip condition is not absolute temperature — it is a sustained delta-from-baseline that the surrounding cells do not share.

In bench tests against staged Li-ion cell-level abuse, the per-vehicle delta crosses the alarm threshold 18–25 minutes before any deck-zone smoke detector trips.

False-positive control

The dominant nuisance source is solar heating through deck openings on coastal sailings. We suppress this with a cross-cell coherence check: if the delta is shared by neighboring cells, it is environmental, not vehicular.

← All Technical Articles